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  • How and where to implement basic authentication in Kibana 3

    - by Jabb
    I have put my elasticsearch server behind a Apache reverse proxy that provides basic authentication. Authenticating to Apache directly from the browser works fine. However, when I use Kibana 3 to access the server, I receive authentication errors. Obviously because no auth headers are sent along with Kibana's Ajax calls. I added the below to elastic-angular-client.js in the Kibana vendor directory to implement authentication quick and dirty. But for some reason it does not work. $http.defaults.headers.common.Authorization = 'Basic ' + Base64Encode('user:Password'); What is the best approach and place to implement basic authentication in Kibana? /*! elastic.js - v1.1.1 - 2013-05-24 * https://github.com/fullscale/elastic.js * Copyright (c) 2013 FullScale Labs, LLC; Licensed MIT */ /*jshint browser:true */ /*global angular:true */ 'use strict'; /* Angular.js service wrapping the elastic.js API. This module can simply be injected into your angular controllers. */ angular.module('elasticjs.service', []) .factory('ejsResource', ['$http', function ($http) { return function (config) { var // use existing ejs object if it exists ejs = window.ejs || {}, /* results are returned as a promise */ promiseThen = function (httpPromise, successcb, errorcb) { return httpPromise.then(function (response) { (successcb || angular.noop)(response.data); return response.data; }, function (response) { (errorcb || angular.noop)(response.data); return response.data; }); }; // check if we have a config object // if not, we have the server url so // we convert it to a config object if (config !== Object(config)) { config = {server: config}; } // set url to empty string if it was not specified if (config.server == null) { config.server = ''; } /* implement the elastic.js client interface for angular */ ejs.client = { server: function (s) { if (s == null) { return config.server; } config.server = s; return this; }, post: function (path, data, successcb, errorcb) { $http.defaults.headers.common.Authorization = 'Basic ' + Base64Encode('user:Password'); console.log($http.defaults.headers); path = config.server + path; var reqConfig = {url: path, data: data, method: 'POST'}; return promiseThen($http(angular.extend(reqConfig, config)), successcb, errorcb); }, get: function (path, data, successcb, errorcb) { $http.defaults.headers.common.Authorization = 'Basic ' + Base64Encode('user:Password'); path = config.server + path; // no body on get request, data will be request params var reqConfig = {url: path, params: data, method: 'GET'}; return promiseThen($http(angular.extend(reqConfig, config)), successcb, errorcb); }, put: function (path, data, successcb, errorcb) { $http.defaults.headers.common.Authorization = 'Basic ' + Base64Encode('user:Password'); path = config.server + path; var reqConfig = {url: path, data: data, method: 'PUT'}; return promiseThen($http(angular.extend(reqConfig, config)), successcb, errorcb); }, del: function (path, data, successcb, errorcb) { $http.defaults.headers.common.Authorization = 'Basic ' + Base64Encode('user:Password'); path = config.server + path; var reqConfig = {url: path, data: data, method: 'DELETE'}; return promiseThen($http(angular.extend(reqConfig, config)), successcb, errorcb); }, head: function (path, data, successcb, errorcb) { $http.defaults.headers.common.Authorization = 'Basic ' + Base64Encode('user:Password'); path = config.server + path; // no body on HEAD request, data will be request params var reqConfig = {url: path, params: data, method: 'HEAD'}; return $http(angular.extend(reqConfig, config)) .then(function (response) { (successcb || angular.noop)(response.headers()); return response.headers(); }, function (response) { (errorcb || angular.noop)(undefined); return undefined; }); } }; return ejs; }; }]); UPDATE 1: I implemented Matts suggestion. However, the server returns a weird response. It seems that the authorization header is not working. Could it have to do with the fact, that I am running Kibana on port 81 and elasticsearch on 8181? OPTIONS /solar_vendor/_search HTTP/1.1 Host: 46.252.46.173:8181 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:25.0) Gecko/20100101 Firefox/25.0 Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8 Accept-Language: de-de,de;q=0.8,en-us;q=0.5,en;q=0.3 Accept-Encoding: gzip, deflate Origin: http://46.252.46.173:81 Access-Control-Request-Method: POST Access-Control-Request-Headers: authorization,content-type Connection: keep-alive Pragma: no-cache Cache-Control: no-cache This is the response HTTP/1.1 401 Authorization Required Date: Fri, 08 Nov 2013 23:47:02 GMT WWW-Authenticate: Basic realm="Username/Password" Vary: Accept-Encoding Content-Encoding: gzip Content-Length: 346 Connection: close Content-Type: text/html; charset=iso-8859-1 UPDATE 2: Updated all instances with the modified headers in these Kibana files root@localhost:/var/www/kibana# grep -r 'ejsResource(' . ./src/app/controllers/dash.js: $scope.ejs = ejsResource({server: config.elasticsearch, headers: {'Access-Control-Request-Headers': 'Accept, Origin, Authorization', 'Authorization': 'Basic XXXXXXXXXXXXXXXXXXXXXXXXXXXXX=='}}); ./src/app/services/querySrv.js: var ejs = ejsResource({server: config.elasticsearch, headers: {'Access-Control-Request-Headers': 'Accept, Origin, Authorization', 'Authorization': 'Basic XXXXXXXXXXXXXXXXXXXXXXXXXXXXX=='}}); ./src/app/services/filterSrv.js: var ejs = ejsResource({server: config.elasticsearch, headers: {'Access-Control-Request-Headers': 'Accept, Origin, Authorization', 'Authorization': 'Basic XXXXXXXXXXXXXXXXXXXXXXXXXXXXX=='}}); ./src/app/services/dashboard.js: var ejs = ejsResource({server: config.elasticsearch, headers: {'Access-Control-Request-Headers': 'Accept, Origin, Authorization', 'Authorization': 'Basic XXXXXXXXXXXXXXXXXXXXXXXXXXXXX=='}}); And modified my vhost conf for the reverse proxy like this <VirtualHost *:8181> ProxyRequests Off ProxyPass / http://127.0.0.1:9200/ ProxyPassReverse / https://127.0.0.1:9200/ <Location /> Order deny,allow Allow from all AuthType Basic AuthName “Username/Password” AuthUserFile /var/www/cake2.2.4/.htpasswd Require valid-user Header always set Access-Control-Allow-Methods "GET, POST, DELETE, OPTIONS, PUT" Header always set Access-Control-Allow-Headers "Content-Type, X-Requested-With, X-HTTP-Method-Override, Origin, Accept, Authorization" Header always set Access-Control-Allow-Credentials "true" Header always set Cache-Control "max-age=0" Header always set Access-Control-Allow-Origin * </Location> ErrorLog ${APACHE_LOG_DIR}/error.log </VirtualHost> Apache sends back the new response headers but the request header still seems to be wrong somewhere. Authentication just doesn't work. Request Headers OPTIONS /solar_vendor/_search HTTP/1.1 Host: 46.252.26.173:8181 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:25.0) Gecko/20100101 Firefox/25.0 Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8 Accept-Language: de-de,de;q=0.8,en-us;q=0.5,en;q=0.3 Accept-Encoding: gzip, deflate Origin: http://46.252.26.173:81 Access-Control-Request-Method: POST Access-Control-Request-Headers: authorization,content-type Connection: keep-alive Pragma: no-cache Cache-Control: no-cache Response Headers HTTP/1.1 401 Authorization Required Date: Sat, 09 Nov 2013 08:48:48 GMT Access-Control-Allow-Methods: GET, POST, DELETE, OPTIONS, PUT Access-Control-Allow-Headers: Content-Type, X-Requested-With, X-HTTP-Method-Override, Origin, Accept, Authorization Access-Control-Allow-Credentials: true Cache-Control: max-age=0 Access-Control-Allow-Origin: * WWW-Authenticate: Basic realm="Username/Password" Vary: Accept-Encoding Content-Encoding: gzip Content-Length: 346 Connection: close Content-Type: text/html; charset=iso-8859-1 SOLUTION: After doing some more research, I found out that this is definitely a configuration issue with regard to CORS. There are quite a few posts available regarding that topic but it appears that in order to solve my problem, it would be necessary to to make some very granular configurations on apache and also make sure that the right stuff is sent from the browser. So I reconsidered the strategy and found a much simpler solution. Just modify the vhost reverse proxy config to move the elastisearch server AND kibana on the same http port. This also adds even better security to Kibana. This is what I did: <VirtualHost *:8181> ProxyRequests Off ProxyPass /bigdatadesk/ http://127.0.0.1:81/bigdatadesk/src/ ProxyPassReverse /bigdatadesk/ http://127.0.0.1:81/bigdatadesk/src/ ProxyPass / http://127.0.0.1:9200/ ProxyPassReverse / https://127.0.0.1:9200/ <Location /> Order deny,allow Allow from all AuthType Basic AuthName “Username/Password” AuthUserFile /var/www/.htpasswd Require valid-user </Location> ErrorLog ${APACHE_LOG_DIR}/error.log </VirtualHost>

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  • New features of C# 4.0

    This article covers New features of C# 4.0. Article has been divided into below sections. Introduction. Dynamic Lookup. Named and Optional Arguments. Features for COM interop. Variance. Relationship with Visual Basic. Resources. Other interested readings… 22 New Features of Visual Studio 2008 for .NET Professionals 50 New Features of SQL Server 2008 IIS 7.0 New features Introduction It is now close to a year since Microsoft Visual C# 3.0 shipped as part of Visual Studio 2008. In the VS Managed Languages team we are hard at work on creating the next version of the language (with the unsurprising working title of C# 4.0), and this document is a first public description of the planned language features as we currently see them. Please be advised that all this is in early stages of production and is subject to change. Part of the reason for sharing our plans in public so early is precisely to get the kind of feedback that will cause us to improve the final product before it rolls out. Simultaneously with the publication of this whitepaper, a first public CTP (community technology preview) of Visual Studio 2010 is going out as a Virtual PC image for everyone to try. Please use it to play and experiment with the features, and let us know of any thoughts you have. We ask for your understanding and patience working with very early bits, where especially new or newly implemented features do not have the quality or stability of a final product. The aim of the CTP is not to give you a productive work environment but to give you the best possible impression of what we are working on for the next release. The CTP contains a number of walkthroughs, some of which highlight the new language features of C# 4.0. Those are excellent for getting a hands-on guided tour through the details of some common scenarios for the features. You may consider this whitepaper a companion document to these walkthroughs, complementing them with a focus on the overall language features and how they work, as opposed to the specifics of the concrete scenarios. C# 4.0 The major theme for C# 4.0 is dynamic programming. Increasingly, objects are “dynamic” in the sense that their structure and behavior is not captured by a static type, or at least not one that the compiler knows about when compiling your program. Some examples include a. objects from dynamic programming languages, such as Python or Ruby b. COM objects accessed through IDispatch c. ordinary .NET types accessed through reflection d. objects with changing structure, such as HTML DOM objects While C# remains a statically typed language, we aim to vastly improve the interaction with such objects. A secondary theme is co-evolution with Visual Basic. Going forward we will aim to maintain the individual character of each language, but at the same time important new features should be introduced in both languages at the same time. They should be differentiated more by style and feel than by feature set. The new features in C# 4.0 fall into four groups: Dynamic lookup Dynamic lookup allows you to write method, operator and indexer calls, property and field accesses, and even object invocations which bypass the C# static type checking and instead gets resolved at runtime. Named and optional parameters Parameters in C# can now be specified as optional by providing a default value for them in a member declaration. When the member is invoked, optional arguments can be omitted. Furthermore, any argument can be passed by parameter name instead of position. COM specific interop features Dynamic lookup as well as named and optional parameters both help making programming against COM less painful than today. On top of that, however, we are adding a number of other small features that further improve the interop experience. Variance It used to be that an IEnumerable<string> wasn’t an IEnumerable<object>. Now it is – C# embraces type safe “co-and contravariance” and common BCL types are updated to take advantage of that. Dynamic Lookup Dynamic lookup allows you a unified approach to invoking things dynamically. With dynamic lookup, when you have an object in your hand you do not need to worry about whether it comes from COM, IronPython, the HTML DOM or reflection; you just apply operations to it and leave it to the runtime to figure out what exactly those operations mean for that particular object. This affords you enormous flexibility, and can greatly simplify your code, but it does come with a significant drawback: Static typing is not maintained for these operations. A dynamic object is assumed at compile time to support any operation, and only at runtime will you get an error if it wasn’t so. Oftentimes this will be no loss, because the object wouldn’t have a static type anyway, in other cases it is a tradeoff between brevity and safety. In order to facilitate this tradeoff, it is a design goal of C# to allow you to opt in or opt out of dynamic behavior on every single call. The dynamic type C# 4.0 introduces a new static type called dynamic. When you have an object of type dynamic you can “do things to it” that are resolved only at runtime: dynamic d = GetDynamicObject(…); d.M(7); The C# compiler allows you to call a method with any name and any arguments on d because it is of type dynamic. At runtime the actual object that d refers to will be examined to determine what it means to “call M with an int” on it. The type dynamic can be thought of as a special version of the type object, which signals that the object can be used dynamically. It is easy to opt in or out of dynamic behavior: any object can be implicitly converted to dynamic, “suspending belief” until runtime. Conversely, there is an “assignment conversion” from dynamic to any other type, which allows implicit conversion in assignment-like constructs: dynamic d = 7; // implicit conversion int i = d; // assignment conversion Dynamic operations Not only method calls, but also field and property accesses, indexer and operator calls and even delegate invocations can be dispatched dynamically: dynamic d = GetDynamicObject(…); d.M(7); // calling methods d.f = d.P; // getting and settings fields and properties d[“one”] = d[“two”]; // getting and setting thorugh indexers int i = d + 3; // calling operators string s = d(5,7); // invoking as a delegate The role of the C# compiler here is simply to package up the necessary information about “what is being done to d”, so that the runtime can pick it up and determine what the exact meaning of it is given an actual object d. Think of it as deferring part of the compiler’s job to runtime. The result of any dynamic operation is itself of type dynamic. Runtime lookup At runtime a dynamic operation is dispatched according to the nature of its target object d: COM objects If d is a COM object, the operation is dispatched dynamically through COM IDispatch. This allows calling to COM types that don’t have a Primary Interop Assembly (PIA), and relying on COM features that don’t have a counterpart in C#, such as indexed properties and default properties. Dynamic objects If d implements the interface IDynamicObject d itself is asked to perform the operation. Thus by implementing IDynamicObject a type can completely redefine the meaning of dynamic operations. This is used intensively by dynamic languages such as IronPython and IronRuby to implement their own dynamic object models. It will also be used by APIs, e.g. by the HTML DOM to allow direct access to the object’s properties using property syntax. Plain objects Otherwise d is a standard .NET object, and the operation will be dispatched using reflection on its type and a C# “runtime binder” which implements C#’s lookup and overload resolution semantics at runtime. This is essentially a part of the C# compiler running as a runtime component to “finish the work” on dynamic operations that was deferred by the static compiler. Example Assume the following code: dynamic d1 = new Foo(); dynamic d2 = new Bar(); string s; d1.M(s, d2, 3, null); Because the receiver of the call to M is dynamic, the C# compiler does not try to resolve the meaning of the call. Instead it stashes away information for the runtime about the call. This information (often referred to as the “payload”) is essentially equivalent to: “Perform an instance method call of M with the following arguments: 1. a string 2. a dynamic 3. a literal int 3 4. a literal object null” At runtime, assume that the actual type Foo of d1 is not a COM type and does not implement IDynamicObject. In this case the C# runtime binder picks up to finish the overload resolution job based on runtime type information, proceeding as follows: 1. Reflection is used to obtain the actual runtime types of the two objects, d1 and d2, that did not have a static type (or rather had the static type dynamic). The result is Foo for d1 and Bar for d2. 2. Method lookup and overload resolution is performed on the type Foo with the call M(string,Bar,3,null) using ordinary C# semantics. 3. If the method is found it is invoked; otherwise a runtime exception is thrown. Overload resolution with dynamic arguments Even if the receiver of a method call is of a static type, overload resolution can still happen at runtime. This can happen if one or more of the arguments have the type dynamic: Foo foo = new Foo(); dynamic d = new Bar(); var result = foo.M(d); The C# runtime binder will choose between the statically known overloads of M on Foo, based on the runtime type of d, namely Bar. The result is again of type dynamic. The Dynamic Language Runtime An important component in the underlying implementation of dynamic lookup is the Dynamic Language Runtime (DLR), which is a new API in .NET 4.0. The DLR provides most of the infrastructure behind not only C# dynamic lookup but also the implementation of several dynamic programming languages on .NET, such as IronPython and IronRuby. Through this common infrastructure a high degree of interoperability is ensured, but just as importantly the DLR provides excellent caching mechanisms which serve to greatly enhance the efficiency of runtime dispatch. To the user of dynamic lookup in C#, the DLR is invisible except for the improved efficiency. However, if you want to implement your own dynamically dispatched objects, the IDynamicObject interface allows you to interoperate with the DLR and plug in your own behavior. This is a rather advanced task, which requires you to understand a good deal more about the inner workings of the DLR. For API writers, however, it can definitely be worth the trouble in order to vastly improve the usability of e.g. a library representing an inherently dynamic domain. Open issues There are a few limitations and things that might work differently than you would expect. · The DLR allows objects to be created from objects that represent classes. However, the current implementation of C# doesn’t have syntax to support this. · Dynamic lookup will not be able to find extension methods. Whether extension methods apply or not depends on the static context of the call (i.e. which using clauses occur), and this context information is not currently kept as part of the payload. · Anonymous functions (i.e. lambda expressions) cannot appear as arguments to a dynamic method call. The compiler cannot bind (i.e. “understand”) an anonymous function without knowing what type it is converted to. One consequence of these limitations is that you cannot easily use LINQ queries over dynamic objects: dynamic collection = …; var result = collection.Select(e => e + 5); If the Select method is an extension method, dynamic lookup will not find it. Even if it is an instance method, the above does not compile, because a lambda expression cannot be passed as an argument to a dynamic operation. There are no plans to address these limitations in C# 4.0. Named and Optional Arguments Named and optional parameters are really two distinct features, but are often useful together. Optional parameters allow you to omit arguments to member invocations, whereas named arguments is a way to provide an argument using the name of the corresponding parameter instead of relying on its position in the parameter list. Some APIs, most notably COM interfaces such as the Office automation APIs, are written specifically with named and optional parameters in mind. Up until now it has been very painful to call into these APIs from C#, with sometimes as many as thirty arguments having to be explicitly passed, most of which have reasonable default values and could be omitted. Even in APIs for .NET however you sometimes find yourself compelled to write many overloads of a method with different combinations of parameters, in order to provide maximum usability to the callers. Optional parameters are a useful alternative for these situations. Optional parameters A parameter is declared optional simply by providing a default value for it: public void M(int x, int y = 5, int z = 7); Here y and z are optional parameters and can be omitted in calls: M(1, 2, 3); // ordinary call of M M(1, 2); // omitting z – equivalent to M(1, 2, 7) M(1); // omitting both y and z – equivalent to M(1, 5, 7) Named and optional arguments C# 4.0 does not permit you to omit arguments between commas as in M(1,,3). This could lead to highly unreadable comma-counting code. Instead any argument can be passed by name. Thus if you want to omit only y from a call of M you can write: M(1, z: 3); // passing z by name or M(x: 1, z: 3); // passing both x and z by name or even M(z: 3, x: 1); // reversing the order of arguments All forms are equivalent, except that arguments are always evaluated in the order they appear, so in the last example the 3 is evaluated before the 1. Optional and named arguments can be used not only with methods but also with indexers and constructors. Overload resolution Named and optional arguments affect overload resolution, but the changes are relatively simple: A signature is applicable if all its parameters are either optional or have exactly one corresponding argument (by name or position) in the call which is convertible to the parameter type. Betterness rules on conversions are only applied for arguments that are explicitly given – omitted optional arguments are ignored for betterness purposes. If two signatures are equally good, one that does not omit optional parameters is preferred. M(string s, int i = 1); M(object o); M(int i, string s = “Hello”); M(int i); M(5); Given these overloads, we can see the working of the rules above. M(string,int) is not applicable because 5 doesn’t convert to string. M(int,string) is applicable because its second parameter is optional, and so, obviously are M(object) and M(int). M(int,string) and M(int) are both better than M(object) because the conversion from 5 to int is better than the conversion from 5 to object. Finally M(int) is better than M(int,string) because no optional arguments are omitted. Thus the method that gets called is M(int). Features for COM interop Dynamic lookup as well as named and optional parameters greatly improve the experience of interoperating with COM APIs such as the Office Automation APIs. In order to remove even more of the speed bumps, a couple of small COM-specific features are also added to C# 4.0. Dynamic import Many COM methods accept and return variant types, which are represented in the PIAs as object. In the vast majority of cases, a programmer calling these methods already knows the static type of a returned object from context, but explicitly has to perform a cast on the returned value to make use of that knowledge. These casts are so common that they constitute a major nuisance. In order to facilitate a smoother experience, you can now choose to import these COM APIs in such a way that variants are instead represented using the type dynamic. In other words, from your point of view, COM signatures now have occurrences of dynamic instead of object in them. This means that you can easily access members directly off a returned object, or you can assign it to a strongly typed local variable without having to cast. To illustrate, you can now say excel.Cells[1, 1].Value = "Hello"; instead of ((Excel.Range)excel.Cells[1, 1]).Value2 = "Hello"; and Excel.Range range = excel.Cells[1, 1]; instead of Excel.Range range = (Excel.Range)excel.Cells[1, 1]; Compiling without PIAs Primary Interop Assemblies are large .NET assemblies generated from COM interfaces to facilitate strongly typed interoperability. They provide great support at design time, where your experience of the interop is as good as if the types where really defined in .NET. However, at runtime these large assemblies can easily bloat your program, and also cause versioning issues because they are distributed independently of your application. The no-PIA feature allows you to continue to use PIAs at design time without having them around at runtime. Instead, the C# compiler will bake the small part of the PIA that a program actually uses directly into its assembly. At runtime the PIA does not have to be loaded. Omitting ref Because of a different programming model, many COM APIs contain a lot of reference parameters. Contrary to refs in C#, these are typically not meant to mutate a passed-in argument for the subsequent benefit of the caller, but are simply another way of passing value parameters. It therefore seems unreasonable that a C# programmer should have to create temporary variables for all such ref parameters and pass these by reference. Instead, specifically for COM methods, the C# compiler will allow you to pass arguments by value to such a method, and will automatically generate temporary variables to hold the passed-in values, subsequently discarding these when the call returns. In this way the caller sees value semantics, and will not experience any side effects, but the called method still gets a reference. Open issues A few COM interface features still are not surfaced in C#. Most notably these include indexed properties and default properties. As mentioned above these will be respected if you access COM dynamically, but statically typed C# code will still not recognize them. There are currently no plans to address these remaining speed bumps in C# 4.0. Variance An aspect of generics that often comes across as surprising is that the following is illegal: IList<string> strings = new List<string>(); IList<object> objects = strings; The second assignment is disallowed because strings does not have the same element type as objects. There is a perfectly good reason for this. If it were allowed you could write: objects[0] = 5; string s = strings[0]; Allowing an int to be inserted into a list of strings and subsequently extracted as a string. This would be a breach of type safety. However, there are certain interfaces where the above cannot occur, notably where there is no way to insert an object into the collection. Such an interface is IEnumerable<T>. If instead you say: IEnumerable<object> objects = strings; There is no way we can put the wrong kind of thing into strings through objects, because objects doesn’t have a method that takes an element in. Variance is about allowing assignments such as this in cases where it is safe. The result is that a lot of situations that were previously surprising now just work. Covariance In .NET 4.0 the IEnumerable<T> interface will be declared in the following way: public interface IEnumerable<out T> : IEnumerable { IEnumerator<T> GetEnumerator(); } public interface IEnumerator<out T> : IEnumerator { bool MoveNext(); T Current { get; } } The “out” in these declarations signifies that the T can only occur in output position in the interface – the compiler will complain otherwise. In return for this restriction, the interface becomes “covariant” in T, which means that an IEnumerable<A> is considered an IEnumerable<B> if A has a reference conversion to B. As a result, any sequence of strings is also e.g. a sequence of objects. This is useful e.g. in many LINQ methods. Using the declarations above: var result = strings.Union(objects); // succeeds with an IEnumerable<object> This would previously have been disallowed, and you would have had to to some cumbersome wrapping to get the two sequences to have the same element type. Contravariance Type parameters can also have an “in” modifier, restricting them to occur only in input positions. An example is IComparer<T>: public interface IComparer<in T> { public int Compare(T left, T right); } The somewhat baffling result is that an IComparer<object> can in fact be considered an IComparer<string>! It makes sense when you think about it: If a comparer can compare any two objects, it can certainly also compare two strings. This property is referred to as contravariance. A generic type can have both in and out modifiers on its type parameters, as is the case with the Func<…> delegate types: public delegate TResult Func<in TArg, out TResult>(TArg arg); Obviously the argument only ever comes in, and the result only ever comes out. Therefore a Func<object,string> can in fact be used as a Func<string,object>. Limitations Variant type parameters can only be declared on interfaces and delegate types, due to a restriction in the CLR. Variance only applies when there is a reference conversion between the type arguments. For instance, an IEnumerable<int> is not an IEnumerable<object> because the conversion from int to object is a boxing conversion, not a reference conversion. Also please note that the CTP does not contain the new versions of the .NET types mentioned above. In order to experiment with variance you have to declare your own variant interfaces and delegate types. COM Example Here is a larger Office automation example that shows many of the new C# features in action. using System; using System.Diagnostics; using System.Linq; using Excel = Microsoft.Office.Interop.Excel; using Word = Microsoft.Office.Interop.Word; class Program { static void Main(string[] args) { var excel = new Excel.Application(); excel.Visible = true; excel.Workbooks.Add(); // optional arguments omitted excel.Cells[1, 1].Value = "Process Name"; // no casts; Value dynamically excel.Cells[1, 2].Value = "Memory Usage"; // accessed var processes = Process.GetProcesses() .OrderByDescending(p =&gt; p.WorkingSet) .Take(10); int i = 2; foreach (var p in processes) { excel.Cells[i, 1].Value = p.ProcessName; // no casts excel.Cells[i, 2].Value = p.WorkingSet; // no casts i++; } Excel.Range range = excel.Cells[1, 1]; // no casts Excel.Chart chart = excel.ActiveWorkbook.Charts. Add(After: excel.ActiveSheet); // named and optional arguments chart.ChartWizard( Source: range.CurrentRegion, Title: "Memory Usage in " + Environment.MachineName); //named+optional chart.ChartStyle = 45; chart.CopyPicture(Excel.XlPictureAppearance.xlScreen, Excel.XlCopyPictureFormat.xlBitmap, Excel.XlPictureAppearance.xlScreen); var word = new Word.Application(); word.Visible = true; word.Documents.Add(); // optional arguments word.Selection.Paste(); } } The code is much more terse and readable than the C# 3.0 counterpart. Note especially how the Value property is accessed dynamically. This is actually an indexed property, i.e. a property that takes an argument; something which C# does not understand. However the argument is optional. Since the access is dynamic, it goes through the runtime COM binder which knows to substitute the default value and call the indexed property. Thus, dynamic COM allows you to avoid accesses to the puzzling Value2 property of Excel ranges. Relationship with Visual Basic A number of the features introduced to C# 4.0 already exist or will be introduced in some form or other in Visual Basic: · Late binding in VB is similar in many ways to dynamic lookup in C#, and can be expected to make more use of the DLR in the future, leading to further parity with C#. · Named and optional arguments have been part of Visual Basic for a long time, and the C# version of the feature is explicitly engineered with maximal VB interoperability in mind. · NoPIA and variance are both being introduced to VB and C# at the same time. VB in turn is adding a number of features that have hitherto been a mainstay of C#. As a result future versions of C# and VB will have much better feature parity, for the benefit of everyone. Resources All available resources concerning C# 4.0 can be accessed through the C# Dev Center. Specifically, this white paper and other resources can be found at the Code Gallery site. Enjoy! span.fullpost {display:none;}

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  • How do I set the encoding statement in the XML declaration when performing an XSL transformation usi

    - by aspiehler
    I wrote a simple package installer in WinBatch that needs to update an XML file with information about the package contents. My first stab at it involved loading the file with Msxml2.DOMDocument, adding nodes and data as required, then saving the data back to disk. This worked well enough, except that it would not create tab and CR/LF whitespace in the new data. The solution I came up with was writing an XSL stylesheet that would recreate the XML file with whitespace added back in. I'm doing this by: loading the XSL file into an Msxml2.FreeThreadedDOMDocument object setting that object as the stylesheet property of an Msxml2.XSLTemplate object creating an XSL processor via Msxml2.XSLTemplate.createProcessor() setting my original Msxml2.DOMDocument as the input property of the XSL processor Calling transform() method of the XSL processor, and saving the output to a file. This works as for as reformatting the XML file with tabs and carriage returns, but my XML declaration comes out either as <?xml version="1.0"?> or <?xml version="1.0" encoding="UTF-16"?> depending on whether I used Msxml2.*.6.0 or Msxml2.* objects (a fall back if the system doesn't have 6.0). If the encoding is set to UTF-16, Msxml12.DOMDocument complains about trying to convert UTF-16 to 1-byte encoding the next time I run my package installer. I've tried creating and adding an XML declaration using both createProcessingInstruction() to both the XML and XSL DOM objects, but neither one seems to affect the output of the XSLTemplate processor. I've also set encoding to UTF-8 in the <xsl:output/> tag in my XSL file. Here is the relevant code in my Winbatch script: xmlDoc = ObjectCreate("Msxml2.DOMDocument.6.0") if !xmlDoc then xmlDoc = ObjectCreate("Msxml2.DOMDocument") xmlDoc.async = @FALSE xmlDoc.validateOnParse = @TRUE xmlDoc.resolveExternals = @TRUE xmlDoc.preserveWhiteSpace = @TRUE xmlDoc.setProperty("SelectionLanguge", "XPath") xmlDoc.setProperty("SelectionNamespaces", "xmlns:fns='http://www.abc.com/f_namespace'") xmlDoc.load(xml_file_path) xslStyleSheet = ObjectCreate("Msxml2.FreeThreadedDOMDocument.6.0") if !xslStyleSheet then xslStyleSheet = ObjectCreate("Msxml2.FreeThreadedDOMDocument") xslStyleSheet.async = @FALSE xslStyleSheet.validateOnParse = @TRUE xslStyleSheet.load(xsl_style_sheet_path) xslTemplate = ObjectCreate("Msxml2.XSLTemplate.6.0") if !xslTemplate then xslTemplate = ObjectCreate("Msxml2.XSLTemplate") xslTemplate.stylesheet = xslStyleSheet processor = xslTemplate.createProcessor() processor.input = xmlDoc processor.transform() ; create a new file and write the XML processor output to it fh = FileOpen(output_file_path, "WRITE" , @FALSE) FileWrite(fh, processor.output) FileClose(fh) The style sheet, with some slight changes to protect the innocent: <?xml version="1.0" encoding="UTF-8"?> <xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.1"> <xsl:output method="xml" indent="yes" encoding="UTF-8"/> <xsl:template match="/"> <fns:test_station xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:fns="http://www.abc.com/f_namespace"> <xsl:for-each select="/fns:test_station/identification"> <xsl:text>&#x0A; </xsl:text> <identification> <xsl:for-each select="./*"> <xsl:text>&#x0A; </xsl:text> <xsl:copy-of select="."/> </xsl:for-each> <xsl:text>&#x0A; </xsl:text> </identification> </xsl:for-each> <xsl:for-each select="/fns:test_station/software"> <xsl:text>&#x0A; </xsl:text> <software> <xsl:for-each select="./package"> <xsl:text>&#x0A; </xsl:text> <package> <xsl:for-each select="./*"> <xsl:text>&#x0A; </xsl:text> <xsl:copy-of select="."/> </xsl:for-each> <xsl:text>&#x0A; </xsl:text> </package> </xsl:for-each> <xsl:text>&#x0A; </xsl:text> </software> </xsl:for-each> <xsl:for-each select="/fns:test_station/calibration"> <xsl:text>&#x0A; </xsl:text> <calibration> <xsl:for-each select="./item"> <xsl:text>&#x0A; </xsl:text> <item> <xsl:for-each select="./*"> <xsl:text>&#x0A; </xsl:text> <xsl:copy-of select="."/> </xsl:for-each> <xsl:text>&#x0A; </xsl:text> </item> </xsl:for-each> <xsl:text>&#x0A; </xsl:text> </calibration> </xsl:for-each> </fns:test_station> </xsl:template> </xsl:stylesheet> And this is a sample output file: <?xml version="1.0" encoding="UTF-16"?> <fns:test_station xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:fns="http://www.abc.com/f_namespace"> <software> <package> <part_number>123456789</part_number> <version>00</version> <test_category>1</test_category> <description>name of software package</description> <execution_path>c:\program files\test\test.exe</execution_path> <execution_arguments>arguments</execution_arguments> <crc_path>c:\ste_config\crc\123456789.lst</crc_path> <uninstall_path>c:\ste_config\uninstall\uninst_123456789.bat</uninstall_path> <install_timestamp>2009-11-09T14:00:44</install_timestamp> </package> </software> </fns:test_station>

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  • How LINQ to Object statements work

    - by rajbk
    This post goes into detail as to now LINQ statements work when querying a collection of objects. This topic assumes you have an understanding of how generics, delegates, implicitly typed variables, lambda expressions, object/collection initializers, extension methods and the yield statement work. I would also recommend you read my previous two posts: Using Delegates in C# Part 1 Using Delegates in C# Part 2 We will start by writing some methods to filter a collection of data. Assume we have an Employee class like so: 1: public class Employee { 2: public int ID { get; set;} 3: public string FirstName { get; set;} 4: public string LastName {get; set;} 5: public string Country { get; set; } 6: } and a collection of employees like so: 1: var employees = new List<Employee> { 2: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 3: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 4: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 5: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" }, 6: }; Filtering We wish to  find all employees that have an even ID. We could start off by writing a method that takes in a list of employees and returns a filtered list of employees with an even ID. 1: static List<Employee> GetEmployeesWithEvenID(List<Employee> employees) { 2: var filteredEmployees = new List<Employee>(); 3: foreach (Employee emp in employees) { 4: if (emp.ID % 2 == 0) { 5: filteredEmployees.Add(emp); 6: } 7: } 8: return filteredEmployees; 9: } The method can be rewritten to return an IEnumerable<Employee> using the yield return keyword. 1: static IEnumerable<Employee> GetEmployeesWithEvenID(IEnumerable<Employee> employees) { 2: foreach (Employee emp in employees) { 3: if (emp.ID % 2 == 0) { 4: yield return emp; 5: } 6: } 7: } We put these together in a console application. 1: using System; 2: using System.Collections.Generic; 3: //No System.Linq 4:  5: public class Program 6: { 7: [STAThread] 8: static void Main(string[] args) 9: { 10: var employees = new List<Employee> { 11: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 12: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 13: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 14: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" }, 15: }; 16: var filteredEmployees = GetEmployeesWithEvenID(employees); 17:  18: foreach (Employee emp in filteredEmployees) { 19: Console.WriteLine("ID {0} First_Name {1} Last_Name {2} Country {3}", 20: emp.ID, emp.FirstName, emp.LastName, emp.Country); 21: } 22:  23: Console.ReadLine(); 24: } 25: 26: static IEnumerable<Employee> GetEmployeesWithEvenID(IEnumerable<Employee> employees) { 27: foreach (Employee emp in employees) { 28: if (emp.ID % 2 == 0) { 29: yield return emp; 30: } 31: } 32: } 33: } 34:  35: public class Employee { 36: public int ID { get; set;} 37: public string FirstName { get; set;} 38: public string LastName {get; set;} 39: public string Country { get; set; } 40: } Output: ID 2 First_Name Jim Last_Name Ashlock Country UK ID 4 First_Name Jill Last_Name Anderson Country AUS Our filtering method is too specific. Let us change it so that it is capable of doing different types of filtering and lets give our method the name Where ;-) We will add another parameter to our Where method. This additional parameter will be a delegate with the following declaration. public delegate bool Filter(Employee emp); The idea is that the delegate parameter in our Where method will point to a method that contains the logic to do our filtering thereby freeing our Where method from any dependency. The method is shown below: 1: static IEnumerable<Employee> Where(IEnumerable<Employee> employees, Filter filter) { 2: foreach (Employee emp in employees) { 3: if (filter(emp)) { 4: yield return emp; 5: } 6: } 7: } Making the change to our app, we create a new instance of the Filter delegate on line 14 with a target set to the method EmployeeHasEvenId. Running the code will produce the same output. 1: public delegate bool Filter(Employee emp); 2:  3: public class Program 4: { 5: [STAThread] 6: static void Main(string[] args) 7: { 8: var employees = new List<Employee> { 9: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 10: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 11: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 12: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" } 13: }; 14: var filterDelegate = new Filter(EmployeeHasEvenId); 15: var filteredEmployees = Where(employees, filterDelegate); 16:  17: foreach (Employee emp in filteredEmployees) { 18: Console.WriteLine("ID {0} First_Name {1} Last_Name {2} Country {3}", 19: emp.ID, emp.FirstName, emp.LastName, emp.Country); 20: } 21: Console.ReadLine(); 22: } 23: 24: static bool EmployeeHasEvenId(Employee emp) { 25: return emp.ID % 2 == 0; 26: } 27: 28: static IEnumerable<Employee> Where(IEnumerable<Employee> employees, Filter filter) { 29: foreach (Employee emp in employees) { 30: if (filter(emp)) { 31: yield return emp; 32: } 33: } 34: } 35: } 36:  37: public class Employee { 38: public int ID { get; set;} 39: public string FirstName { get; set;} 40: public string LastName {get; set;} 41: public string Country { get; set; } 42: } Lets use lambda expressions to inline the contents of the EmployeeHasEvenId method in place of the method. The next code snippet shows this change (see line 15).  For brevity, the Employee class declaration has been skipped. 1: public delegate bool Filter(Employee emp); 2:  3: public class Program 4: { 5: [STAThread] 6: static void Main(string[] args) 7: { 8: var employees = new List<Employee> { 9: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 10: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 11: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 12: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" } 13: }; 14: var filterDelegate = new Filter(EmployeeHasEvenId); 15: var filteredEmployees = Where(employees, emp => emp.ID % 2 == 0); 16:  17: foreach (Employee emp in filteredEmployees) { 18: Console.WriteLine("ID {0} First_Name {1} Last_Name {2} Country {3}", 19: emp.ID, emp.FirstName, emp.LastName, emp.Country); 20: } 21: Console.ReadLine(); 22: } 23: 24: static bool EmployeeHasEvenId(Employee emp) { 25: return emp.ID % 2 == 0; 26: } 27: 28: static IEnumerable<Employee> Where(IEnumerable<Employee> employees, Filter filter) { 29: foreach (Employee emp in employees) { 30: if (filter(emp)) { 31: yield return emp; 32: } 33: } 34: } 35: } 36:  The output displays the same two employees.  Our Where method is too restricted since it works with a collection of Employees only. Lets change it so that it works with any IEnumerable<T>. In addition, you may recall from my previous post,  that .NET 3.5 comes with a lot of predefined delegates including public delegate TResult Func<T, TResult>(T arg); We will get rid of our Filter delegate and use the one above instead. We apply these two changes to our code. 1: public class Program 2: { 3: [STAThread] 4: static void Main(string[] args) 5: { 6: var employees = new List<Employee> { 7: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 8: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 9: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 10: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" } 11: }; 12:  13: var filteredEmployees = Where(employees, emp => emp.ID % 2 == 0); 14:  15: foreach (Employee emp in filteredEmployees) { 16: Console.WriteLine("ID {0} First_Name {1} Last_Name {2} Country {3}", 17: emp.ID, emp.FirstName, emp.LastName, emp.Country); 18: } 19: Console.ReadLine(); 20: } 21: 22: static IEnumerable<T> Where<T>(IEnumerable<T> source, Func<T, bool> filter) { 23: foreach (var x in source) { 24: if (filter(x)) { 25: yield return x; 26: } 27: } 28: } 29: } We have successfully implemented a way to filter any IEnumerable<T> based on a  filter criteria. Projection Now lets enumerate on the items in the IEnumerable<Employee> we got from the Where method and copy them into a new IEnumerable<EmployeeFormatted>. The EmployeeFormatted class will only have a FullName and ID property. 1: public class EmployeeFormatted { 2: public int ID { get; set; } 3: public string FullName {get; set;} 4: } We could “project” our existing IEnumerable<Employee> into a new collection of IEnumerable<EmployeeFormatted> with the help of a new method. We will call this method Select ;-) 1: static IEnumerable<EmployeeFormatted> Select(IEnumerable<Employee> employees) { 2: foreach (var emp in employees) { 3: yield return new EmployeeFormatted { 4: ID = emp.ID, 5: FullName = emp.LastName + ", " + emp.FirstName 6: }; 7: } 8: } The changes are applied to our app. 1: public class Program 2: { 3: [STAThread] 4: static void Main(string[] args) 5: { 6: var employees = new List<Employee> { 7: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 8: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 9: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 10: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" } 11: }; 12:  13: var filteredEmployees = Where(employees, emp => emp.ID % 2 == 0); 14: var formattedEmployees = Select(filteredEmployees); 15:  16: foreach (EmployeeFormatted emp in formattedEmployees) { 17: Console.WriteLine("ID {0} Full_Name {1}", 18: emp.ID, emp.FullName); 19: } 20: Console.ReadLine(); 21: } 22:  23: static IEnumerable<T> Where<T>(IEnumerable<T> source, Func<T, bool> filter) { 24: foreach (var x in source) { 25: if (filter(x)) { 26: yield return x; 27: } 28: } 29: } 30: 31: static IEnumerable<EmployeeFormatted> Select(IEnumerable<Employee> employees) { 32: foreach (var emp in employees) { 33: yield return new EmployeeFormatted { 34: ID = emp.ID, 35: FullName = emp.LastName + ", " + emp.FirstName 36: }; 37: } 38: } 39: } 40:  41: public class Employee { 42: public int ID { get; set;} 43: public string FirstName { get; set;} 44: public string LastName {get; set;} 45: public string Country { get; set; } 46: } 47:  48: public class EmployeeFormatted { 49: public int ID { get; set; } 50: public string FullName {get; set;} 51: } Output: ID 2 Full_Name Ashlock, Jim ID 4 Full_Name Anderson, Jill We have successfully selected employees who have an even ID and then shaped our data with the help of the Select method so that the final result is an IEnumerable<EmployeeFormatted>.  Lets make our Select method more generic so that the user is given the freedom to shape what the output would look like. We can do this, like before, with lambda expressions. Our Select method is changed to accept a delegate as shown below. TSource will be the type of data that comes in and TResult will be the type the user chooses (shape of data) as returned from the selector delegate. 1:  2: static IEnumerable<TResult> Select<TSource, TResult>(IEnumerable<TSource> source, Func<TSource, TResult> selector) { 3: foreach (var x in source) { 4: yield return selector(x); 5: } 6: } We see the new changes to our app. On line 15, we use lambda expression to specify the shape of the data. In this case the shape will be of type EmployeeFormatted. 1:  2: public class Program 3: { 4: [STAThread] 5: static void Main(string[] args) 6: { 7: var employees = new List<Employee> { 8: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 9: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 10: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 11: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" } 12: }; 13:  14: var filteredEmployees = Where(employees, emp => emp.ID % 2 == 0); 15: var formattedEmployees = Select(filteredEmployees, (emp) => 16: new EmployeeFormatted { 17: ID = emp.ID, 18: FullName = emp.LastName + ", " + emp.FirstName 19: }); 20:  21: foreach (EmployeeFormatted emp in formattedEmployees) { 22: Console.WriteLine("ID {0} Full_Name {1}", 23: emp.ID, emp.FullName); 24: } 25: Console.ReadLine(); 26: } 27: 28: static IEnumerable<T> Where<T>(IEnumerable<T> source, Func<T, bool> filter) { 29: foreach (var x in source) { 30: if (filter(x)) { 31: yield return x; 32: } 33: } 34: } 35: 36: static IEnumerable<TResult> Select<TSource, TResult>(IEnumerable<TSource> source, Func<TSource, TResult> selector) { 37: foreach (var x in source) { 38: yield return selector(x); 39: } 40: } 41: } The code outputs the same result as before. On line 14 we filter our data and on line 15 we project our data. What if we wanted to be more expressive and concise? We could combine both line 14 and 15 into one line as shown below. Assuming you had to perform several operations like this on our collection, you would end up with some very unreadable code! 1: var formattedEmployees = Select(Where(employees, emp => emp.ID % 2 == 0), (emp) => 2: new EmployeeFormatted { 3: ID = emp.ID, 4: FullName = emp.LastName + ", " + emp.FirstName 5: }); A cleaner way to write this would be to give the appearance that the Select and Where methods were part of the IEnumerable<T>. This is exactly what extension methods give us. Extension methods have to be defined in a static class. Let us make the Select and Where extension methods on IEnumerable<T> 1: public static class MyExtensionMethods { 2: static IEnumerable<T> Where<T>(this IEnumerable<T> source, Func<T, bool> filter) { 3: foreach (var x in source) { 4: if (filter(x)) { 5: yield return x; 6: } 7: } 8: } 9: 10: static IEnumerable<TResult> Select<TSource, TResult>(this IEnumerable<TSource> source, Func<TSource, TResult> selector) { 11: foreach (var x in source) { 12: yield return selector(x); 13: } 14: } 15: } The creation of the extension method makes the syntax much cleaner as shown below. We can write as many extension methods as we want and keep on chaining them using this technique. 1: var formattedEmployees = employees 2: .Where(emp => emp.ID % 2 == 0) 3: .Select (emp => new EmployeeFormatted { ID = emp.ID, FullName = emp.LastName + ", " + emp.FirstName }); Making these changes and running our code produces the same result. 1: using System; 2: using System.Collections.Generic; 3:  4: public class Program 5: { 6: [STAThread] 7: static void Main(string[] args) 8: { 9: var employees = new List<Employee> { 10: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 11: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 12: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 13: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" } 14: }; 15:  16: var formattedEmployees = employees 17: .Where(emp => emp.ID % 2 == 0) 18: .Select (emp => 19: new EmployeeFormatted { 20: ID = emp.ID, 21: FullName = emp.LastName + ", " + emp.FirstName 22: } 23: ); 24:  25: foreach (EmployeeFormatted emp in formattedEmployees) { 26: Console.WriteLine("ID {0} Full_Name {1}", 27: emp.ID, emp.FullName); 28: } 29: Console.ReadLine(); 30: } 31: } 32:  33: public static class MyExtensionMethods { 34: static IEnumerable<T> Where<T>(this IEnumerable<T> source, Func<T, bool> filter) { 35: foreach (var x in source) { 36: if (filter(x)) { 37: yield return x; 38: } 39: } 40: } 41: 42: static IEnumerable<TResult> Select<TSource, TResult>(this IEnumerable<TSource> source, Func<TSource, TResult> selector) { 43: foreach (var x in source) { 44: yield return selector(x); 45: } 46: } 47: } 48:  49: public class Employee { 50: public int ID { get; set;} 51: public string FirstName { get; set;} 52: public string LastName {get; set;} 53: public string Country { get; set; } 54: } 55:  56: public class EmployeeFormatted { 57: public int ID { get; set; } 58: public string FullName {get; set;} 59: } Let’s change our code to return a collection of anonymous types and get rid of the EmployeeFormatted type. We see that the code produces the same output. 1: using System; 2: using System.Collections.Generic; 3:  4: public class Program 5: { 6: [STAThread] 7: static void Main(string[] args) 8: { 9: var employees = new List<Employee> { 10: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 11: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 12: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 13: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" } 14: }; 15:  16: var formattedEmployees = employees 17: .Where(emp => emp.ID % 2 == 0) 18: .Select (emp => 19: new { 20: ID = emp.ID, 21: FullName = emp.LastName + ", " + emp.FirstName 22: } 23: ); 24:  25: foreach (var emp in formattedEmployees) { 26: Console.WriteLine("ID {0} Full_Name {1}", 27: emp.ID, emp.FullName); 28: } 29: Console.ReadLine(); 30: } 31: } 32:  33: public static class MyExtensionMethods { 34: public static IEnumerable<T> Where<T>(this IEnumerable<T> source, Func<T, bool> filter) { 35: foreach (var x in source) { 36: if (filter(x)) { 37: yield return x; 38: } 39: } 40: } 41: 42: public static IEnumerable<TResult> Select<TSource, TResult>(this IEnumerable<TSource> source, Func<TSource, TResult> selector) { 43: foreach (var x in source) { 44: yield return selector(x); 45: } 46: } 47: } 48:  49: public class Employee { 50: public int ID { get; set;} 51: public string FirstName { get; set;} 52: public string LastName {get; set;} 53: public string Country { get; set; } 54: } To be more expressive, C# allows us to write our extension method calls as a query expression. Line 16 can be rewritten a query expression like so: 1: var formattedEmployees = from emp in employees 2: where emp.ID % 2 == 0 3: select new { 4: ID = emp.ID, 5: FullName = emp.LastName + ", " + emp.FirstName 6: }; When the compiler encounters an expression like the above, it simply rewrites it as calls to our extension methods.  So far we have been using our extension methods. The System.Linq namespace contains several extension methods for objects that implement the IEnumerable<T>. You can see a listing of these methods in the Enumerable class in the System.Linq namespace. Let’s get rid of our extension methods (which I purposefully wrote to be of the same signature as the ones in the Enumerable class) and use the ones provided in the Enumerable class. Our final code is shown below: 1: using System; 2: using System.Collections.Generic; 3: using System.Linq; //Added 4:  5: public class Program 6: { 7: [STAThread] 8: static void Main(string[] args) 9: { 10: var employees = new List<Employee> { 11: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 12: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 13: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 14: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" } 15: }; 16:  17: var formattedEmployees = from emp in employees 18: where emp.ID % 2 == 0 19: select new { 20: ID = emp.ID, 21: FullName = emp.LastName + ", " + emp.FirstName 22: }; 23:  24: foreach (var emp in formattedEmployees) { 25: Console.WriteLine("ID {0} Full_Name {1}", 26: emp.ID, emp.FullName); 27: } 28: Console.ReadLine(); 29: } 30: } 31:  32: public class Employee { 33: public int ID { get; set;} 34: public string FirstName { get; set;} 35: public string LastName {get; set;} 36: public string Country { get; set; } 37: } 38:  39: public class EmployeeFormatted { 40: public int ID { get; set; } 41: public string FullName {get; set;} 42: } This post has shown you a basic overview of LINQ to Objects work by showning you how an expression is converted to a sequence of calls to extension methods when working directly with objects. It gets more interesting when working with LINQ to SQL where an expression tree is constructed – an in memory data representation of the expression. The C# compiler compiles these expressions into code that builds an expression tree at runtime. The provider can then traverse the expression tree and generate the appropriate SQL query. You can read more about expression trees in this MSDN article.

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  • Design by Contract with Microsoft .Net Code Contract

    - by Fredrik N
    I have done some talks on different events and summits about Defensive Programming and Design by Contract, last time was at Cornerstone’s Developer Summit 2010. Next time will be at SweNug (Sweden .Net User Group). I decided to write a blog post about of some stuffs I was talking about. Users are a terrible thing! Protect your self from them ”Human users have a gift for doing the worst possible thing at the worst possible time.” – Michael T. Nygard, Release It! The kind of users Michael T. Nygard are talking about is the users of a system. We also have users that uses our code, the users I’m going to focus on is the users of our code. Me and you and another developers. “Any fool can write code that a computer can understand. Good programmers write code that humans can understand.” – Martin Fowler Good programmers also writes code that humans know how to use, good programmers also make sure software behave in a predictable manner despise inputs or user actions. Design by Contract   Design by Contract (DbC) is a way for us to make a contract between us (the code writer) and the users of our code. It’s about “If you give me this, I promise to give you this”. It’s not about business validations, that is something completely different that should be part of the domain model. DbC is to make sure the users of our code uses it in a correct way, and that we can rely on the contract and write code in a way where we know that the users will follow the contract. It will make it much easier for us to write code with a contract specified. Something like the following code is something we may see often: public void DoSomething(Object value) { value.DoIKnowThatICanDoThis(); } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Where “value” can be uses directly or passed to other methods and later be used. What some of us can easily forget here is that the “value” can be “null”. We will probably not passing a null value, but someone else that uses our code maybe will do it. I think most of you (including me) have passed “null” into a method because you don’t know if the argument need to be specified to a valid value etc. I bet most of you also have got the “Null reference exception”. Sometimes this “Null reference exception” can be hard and take time to fix, because we need to search among our code to see where the “null” value was passed in etc. Wouldn’t it be much better if we can as early as possible specify that the value can’t not be null, so the users of our code also know it when the users starts to use our code, and before run time execution of the code? This is where DbC comes into the picture. We can use DbC to specify what we need, and by doing so we can rely on the contract when we write our code. So the code above can actually use the DoIKnowThatICanDoThis() method on the value object without being worried that the “value” can be null. The contract between the users of the code and us writing the code, says that the “value” can’t be null.   Pre- and Postconditions   When working with DbC we are specifying pre- and postconditions.  Precondition is a condition that should be met before a query or command is executed. An example of a precondition is: “The Value argument of the method can’t be null”, and we make sure the “value” isn’t null before the method is called. Postcondition is a condition that should be met when a command or query is completed, a postcondition will make sure the result is correct. An example of a postconditon is “The method will return a list with at least 1 item”. Commands an Quires When using DbC, we need to know what a Command and a Query is, because some principles that can be good to follow are based on commands and queries. A Command is something that will not return anything, like the SQL’s CREATE, UPDATE and DELETE. There are two kinds of Commands when using DbC, the Creation commands (for example a Constructor), and Others. Others can for example be a Command to add a value to a list, remove or update a value etc. //Creation commands public Stack(int size) //Other commands public void Push(object value); public void Remove(); .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   A Query, is something that will return something, for example an Attribute, Property or a Function, like the SQL’s SELECT.   There are two kinds of Queries, the Basic Queries  (Quires that aren’t based on another queries), and the Derived Queries, queries that is based on another queries. Here is an example of queries of a Stack: //Basic Queries public int Count; public object this[int index] { get; } //Derived Queries //Is related to Count Query public bool IsEmpty() { return Count == 0; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } To understand about some principles that are good to follow when using DbC, we need to know about the Commands and different Queries. The 6 Principles When working with DbC, it’s advisable to follow some principles to make it easier to define and use contracts. The following DbC principles are: Separate commands and queries. Separate basic queries from derived queries. For each derived query, write a postcondition that specifies what result will be returned, in terms of one or more basic queries. For each command, write a postcondition that specifies the value of every basic query. For every query and command, decide on a suitable precondition. Write invariants to define unchanging properties of objects. Before I will write about each of them I want you to now that I’m going to use .Net 4.0 Code Contract. I will in the rest of the post uses a simple Stack (Yes I know, .Net already have a Stack class) to give you the basic understanding about using DbC. A Stack is a data structure where the first item in, will be the first item out. Here is a basic implementation of a Stack where not contract is specified yet: public class Stack { private object[] _array; //Basic Queries public uint Count; public object this[uint index] { get { return _array[index]; } set { _array[index] = value; } } //Derived Queries //Is related to Count Query public bool IsEmpty() { return Count == 0; } //Is related to Count and this[] Query public object Top() { return this[Count]; } //Creation commands public Stack(uint size) { Count = 0; _array = new object[size]; } //Other commands public void Push(object value) { this[++Count] = value; } public void Remove() { this[Count] = null; Count--; } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   Note: The Stack is implemented in a way to demonstrate the use of Code Contract in a simple way, the implementation may not look like how you would implement it, so don’t think this is the perfect Stack implementation, only used for demonstration.   Before I will go deeper into the principles I will simply mention how we can use the .Net Code Contract. I mention before about pre- and postcondition, is about “Require” something and to “Ensure” something. When using Code Contract, we will use a static class called “Contract” and is located in he “System.Diagnostics.Contracts” namespace. The contract must be specified at the top or our member statement block. To specify a precondition with Code Contract we uses the Contract.Requires method, and to specify a postcondition, we uses the Contract.Ensure method. Here is an example where both a pre- and postcondition are used: public object Top() { Contract.Requires(Count > 0, "Stack is empty"); Contract.Ensures(Contract.Result<object>() == this[Count]); return this[Count]; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   The contract above requires that the Count is greater than 0, if not we can’t get the item at the Top of a Stack. We also Ensures that the results (By using the Contract.Result method, we can specify a postcondition that will check if the value returned from a method is correct) of the Top query is equal to this[Count].   1. Separate Commands and Queries   When working with DbC, it’s important to separate Command and Quires. A method should either be a command that performs an Action, or returning information to the caller, not both. By asking a question the answer shouldn’t be changed. The following is an example of a Command and a Query of a Stack: public void Push(object value) public object Top() .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   The Push is a command and will not return anything, just add a value to the Stack, the Top is a query to get the item at the top of the stack.   2. Separate basic queries from derived queries There are two different kinds of queries,  the basic queries that doesn’t rely on another queries, and derived queries that uses a basic query. The “Separate basic queries from derived queries” principle is about about that derived queries can be specified in terms of basic queries. So this principles is more about recognizing that a query is a derived query or a basic query. It will then make is much easier to follow the other principles. The following code shows a basic query and a derived query: //Basic Queries public uint Count; //Derived Queries //Is related to Count Query public bool IsEmpty() { return Count == 0; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   We can see that IsEmpty will use the Count query, and that makes the IsEmpty a Derived query.   3. For each derived query, write a postcondition that specifies what result will be returned, in terms of one or more basic queries.   When the derived query is recognize we can follow the 3ed principle. For each derived query, we can create a postcondition that specifies what result our derived query will return in terms of one or more basic queries. Remember that DbC is about contracts between the users of the code and us writing the code. So we can’t use demand that the users will pass in a valid value, we must also ensure that we will give the users what the users wants, when the user is following our contract. The IsEmpty query of the Stack will use a Count query and that will make the IsEmpty a Derived query, so we should now write a postcondition that specified what results will be returned, in terms of using a basic query and in this case the Count query, //Basic Queries public uint Count; //Derived Queries public bool IsEmpty() { Contract.Ensures(Contract.Result<bool>() == (Count == 0)); return Count == 0; } The Contract.Ensures is used to create a postcondition. The above code will make sure that the results of the IsEmpty (by using the Contract.Result to get the result of the IsEmpty method) is correct, that will say that the IsEmpty will be either true or false based on Count is equal to 0 or not. The postcondition are using a basic query, so the IsEmpty is now following the 3ed principle. We also have another Derived Query, the Top query, it will also need a postcondition and it uses all basic queries. The Result of the Top method must be the same value as the this[] query returns. //Basic Queries public uint Count; public object this[uint index] { get { return _array[index]; } set { _array[index] = value; } } //Derived Queries //Is related to Count and this[] Query public object Top() { Contract.Ensures(Contract.Result<object>() == this[Count]); return this[Count]; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   4. For each command, write a postcondition that specifies the value of every basic query.   For each command we will create a postconditon that specifies the value of basic queries. If we look at the Stack implementation we will have three Commands, one Creation command, the Constructor, and two others commands, Push and Remove. Those commands need a postcondition and they should include basic query to follow the 4th principle. //Creation commands public Stack(uint size) { Contract.Ensures(Count == 0); Count = 0; _array = new object[size]; } //Other commands public void Push(object value) { Contract.Ensures(Count == Contract.OldValue<uint>(Count) + 1); Contract.Ensures(this[Count] == value); this[++Count] = value; } public void Remove() { Contract.Ensures(Count == Contract.OldValue<uint>(Count) - 1); this[Count] = null; Count--; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   As you can see the Create command will Ensures that Count will be 0 when the Stack is created, when a Stack is created there shouldn’t be any items in the stack. The Push command will take a value and put it into the Stack, when an item is pushed into the Stack, the Count need to be increased to know the number of items added to the Stack, and we must also make sure the item is really added to the Stack. The postconditon of the Push method will make sure the that old value of the Count (by using the Contract.OldValue we can get the value a Query has before the method is called)  plus 1 will be equal to the Count query, this is the way we can ensure that the Push will increase the Count with one. We also make sure the this[] query will now contain the item we pushed into the Stack. The Remove method must make sure the Count is decreased by one when the top item is removed from the Stack. The Commands is now following the 4th principle, where each command now have a postcondition that used the value of basic queries. Note: The principle says every basic Query, the Remove only used one Query the Count, it’s because this command can’t use the this[] query because an item is removed, so the only way to make sure an item is removed is to just use the Count query, so the Remove will still follow the principle.   5. For every query and command, decide on a suitable precondition.   We have now focused only on postcondition, now time for some preconditons. The 5th principle is about deciding a suitable preconditon for every query and command. If we starts to look at one of our basic queries (will not go through all Queries and commands here, just some of them) the this[] query, we can’t pass an index that is lower then 1 (.Net arrays and list are zero based, but not the stack in this blog post ;)) and the index can’t be lesser than the number of items in the stack. So here we will need a preconditon. public object this[uint index] { get { Contract.Requires(index >= 1); Contract.Requires(index <= Count); return _array[index]; } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Think about the Contract as an documentation about how to use the code in a correct way, so if the contract could be specified elsewhere (not part of the method body), we could simply write “return _array[index]” and there is no need to check if index is greater or lesser than Count, because that is specified in a “contract”. The implementation of Code Contract, requires that the contract is specified in the code. As a developer I would rather have this contract elsewhere (Like Spec#) or implemented in a way Eiffel uses it as part of the language. Now when we have looked at one Query, we can also look at one command, the Remove command (You can see the whole implementation of the Stack at the end of this blog post, where precondition is added to more queries and commands then what I’m going to show in this section). We can only Remove an item if the Count is greater than 0. So we can write a precondition that will require that Count must be greater than 0. public void Remove() { Contract.Requires(Count > 0); Contract.Ensures(Count == Contract.OldValue<uint>(Count) - 1); this[Count] = null; Count--; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   6. Write invariants to define unchanging properties of objects.   The last principle is about making sure the object are feeling great! This is done by using invariants. When using Code Contract we can specify invariants by adding a method with the attribute ContractInvariantMethod, the method must be private or public and can only contains calls to Contract.Invariant. To make sure the Stack feels great, the Stack must have 0 or more items, the Count can’t never be a negative value to make sure each command and queries can be used of the Stack. Here is our invariant for the Stack object: [ContractInvariantMethod] private void ObjectInvariant() { Contract.Invariant(Count >= 0); } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   Note: The ObjectInvariant method will be called every time after a Query or Commands is called. Here is the full example using Code Contract:   public class Stack { private object[] _array; //Basic Queries public uint Count; public object this[uint index] { get { Contract.Requires(index >= 1); Contract.Requires(index <= Count); return _array[index]; } set { Contract.Requires(index >= 1); Contract.Requires(index <= Count); _array[index] = value; } } //Derived Queries //Is related to Count Query public bool IsEmpty() { Contract.Ensures(Contract.Result<bool>() == (Count == 0)); return Count == 0; } //Is related to Count and this[] Query public object Top() { Contract.Requires(Count > 0, "Stack is empty"); Contract.Ensures(Contract.Result<object>() == this[Count]); return this[Count]; } //Creation commands public Stack(uint size) { Contract.Requires(size > 0); Contract.Ensures(Count == 0); Count = 0; _array = new object[size]; } //Other commands public void Push(object value) { Contract.Requires(value != null); Contract.Ensures(Count == Contract.OldValue<uint>(Count) + 1); Contract.Ensures(this[Count] == value); this[++Count] = value; } public void Remove() { Contract.Requires(Count > 0); Contract.Ensures(Count == Contract.OldValue<uint>(Count) - 1); this[Count] = null; Count--; } [ContractInvariantMethod] private void ObjectInvariant() { Contract.Invariant(Count >= 0); } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Summary By using Design By Contract we can make sure the users are using our code in a correct way, and we must also make sure the users will get the expected results when they uses our code. This can be done by specifying contracts. To make it easy to use Design By Contract, some principles may be good to follow like the separation of commands an queries. With .Net 4.0 we can use the Code Contract feature to specify contracts.

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  • Conversion from YUV444 to RGB888

    - by Abhi
    I am new in this field and i desperately need some guidance from u all. I have to support yuv444 to rgb 888 in display driver module. There is one test which i have done for yv12 → rgb565 in wince 6.0 r3 which is mentioned below. //------------------------------------------------------------------------------ // // Function: PP_CSC_YV12_RGB565Test // // This function tests the Post-processor // // // // Parameters: // uiMsg // [in] Ignored. // // tpParam // [in] Ignored. // // lpFTE // [in] Ignored. // // Returns: // Specifies if the test passed (TPR_PASS), failed (TPR_FAIL), or was // skipped (TPR_SKIP). // // TESTPROCAPI PP_CSC_YV12_RGB565Test(UINT uMsg, TPPARAM tpParam, LPFUNCTION_TABLE_ENTRY lpFTE) { LogEntry(L"%d : In %s Function \r\n",++abhineet,__WFUNCTION__); UNREFERENCED_PARAMETER(tpParam); UNREFERENCED_PARAMETER(lpFTE); DWORD dwResult= TPR_SKIP; ppConfigData ppData; DWORD iInputBytesPerFrame, iOutputBytesPerFrame; UINT32 iInputStride, iOutputStride; UINT16 iOutputWidth, iOutputHeight, iOutputBPP; UINT16 iInputWidth, iInputHeight, iInputBPP; int iOption; PP_TEST_FUNCTION_ENTRY(); // Validate that the shell wants the test to run if (uMsg != TPM_EXECUTE) { return TPR_NOT_HANDLED; } PPTestInit(); iInputWidth = PP_TEST_FRAME_WIDTH; //116 iInputHeight = PP_TEST_FRAME_HEIGHT; //160 iInputBPP = PP_TEST_FRAME_BPP; //2 iInputStride = iInputWidth * 3/2; // YV12 is 12 bits per pixel iOutputWidth = PP_TEST_FRAME_WIDTH; iOutputHeight = PP_TEST_FRAME_HEIGHT; iOutputBPP = PP_TEST_FRAME_BPP; iOutputStride = iOutputWidth * iOutputBPP; // Allocate buffers for input and output frames iInputBytesPerFrame = iInputStride * iInputHeight; pInputFrameVirtAddr = (UINT32 *) AllocPhysMem(iInputBytesPerFrame, PAGE_EXECUTE_READWRITE, 0, 0, (ULONG *) &pInputFramePhysAddr); iOutputBytesPerFrame = iOutputStride * iOutputHeight; pOutputFrameVirtAddr = (UINT32 *) AllocPhysMem(iOutputBytesPerFrame, PAGE_EXECUTE_READWRITE, 0, 0, (ULONG *) &pOutputFramePhysAddr); if ((NULL == pInputFrameVirtAddr) || (NULL == pOutputFrameVirtAddr)) { dwResult = TPR_FAIL; goto PP_CSC_YV12_RGB565Test_clean_up; } //----------------------------- // Configure PP //----------------------------- // Set up post-processing configuration data memset(&ppData, 0 , sizeof(ppData)); // Set up input format and data width ppData.inputIDMAChannel.FrameFormat = icFormat_YUV420; ppData.inputIDMAChannel.DataWidth = icDataWidth_8BPP; // dummy value for YUV ppData.inputIDMAChannel.PixelFormat.component0_offset = 0; ppData.inputIDMAChannel.PixelFormat.component1_offset = 8; ppData.inputIDMAChannel.PixelFormat.component2_offset = 16; ppData.inputIDMAChannel.PixelFormat.component3_offset = 24; ppData.inputIDMAChannel.PixelFormat.component0_width = 8-1; ppData.inputIDMAChannel.PixelFormat.component1_width = 8-1; ppData.inputIDMAChannel.PixelFormat.component2_width = 8-1; ppData.inputIDMAChannel.PixelFormat.component3_width = 8-1; ppData.inputIDMAChannel.FrameSize.height = iInputHeight; ppData.inputIDMAChannel.FrameSize.width = iInputWidth; ppData.inputIDMAChannel.LineStride = iInputWidth; // Set up output format and data width ppData.outputIDMAChannel.FrameFormat = icFormat_RGB; ppData.outputIDMAChannel.DataWidth = icDataWidth_16BPP; ppData.outputIDMAChannel.PixelFormat.component0_offset = RGB_COMPONET0_OFFSET; ppData.outputIDMAChannel.PixelFormat.component1_offset = RGB_COMPONET1_OFFSET; ppData.outputIDMAChannel.PixelFormat.component2_offset = RGB_COMPONET2_OFFSET; ppData.outputIDMAChannel.PixelFormat.component3_offset = RGB_COMPONET3_OFFSET; ppData.outputIDMAChannel.PixelFormat.component0_width = RGB_COMPONET0_WIDTH -1; ppData.outputIDMAChannel.PixelFormat.component1_width = RGB_COMPONET1_WIDTH -1; ppData.outputIDMAChannel.PixelFormat.component2_width = RGB_COMPONET2_WIDTH -1; ppData.outputIDMAChannel.PixelFormat.component3_width = RGB_COMPONET3_WIDTH; ppData.outputIDMAChannel.FrameSize.height = iOutputHeight; ppData.outputIDMAChannel.FrameSize.width = iOutputWidth; ppData.outputIDMAChannel.LineStride = iOutputStride; // Set up post-processing channel CSC parameters // based on input and output ppData.CSCEquation = CSCY2R_A1; ppData.inputIDMAChannel.UBufOffset = iInputHeight * iInputWidth + (iInputHeight * iInputWidth)/4; ppData.inputIDMAChannel.VBufOffset = iInputHeight * iInputWidth; ppData.FlipRot.verticalFlip = FALSE; ppData.FlipRot.horizontalFlip = FALSE; ppData.FlipRot.rotate90 = FALSE; if (!PPConfigure(hPP, &ppData)) { dwResult = TPR_FAIL; goto PP_CSC_YV12_RGB565Test_clean_up; } //----------------------------- // Read first input buffer //----------------------------- // Read Input file for new frame if (!ReadImage(PP_TEST_YV12_FILENAME,pInputFrameVirtAddr,iInputBytesPerFrame,PP_TEST_FRAME_WIDTH,PP_TEST_FRAME_HEIGHT)) { g_pKato->Log(PP_ZONE_ERROR, (TEXT("fail to ReadImage()!\r\n"))); dwResult = TPR_FAIL; goto PP_CSC_YV12_RGB565Test_clean_up; } //----------------------------- // Start PP //----------------------------- if (!PPStart(hPP)) { dwResult = TPR_FAIL; goto PP_CSC_YV12_RGB565Test_clean_up; } if (!PPInterruptEnable(hPP, FRAME_INTERRUPT)) { dwResult = TPR_FAIL; goto PP_CSC_YV12_RGB565Test_clean_up; } //----------------------------- // Queue Input/Output Buffers //----------------------------- UINT32 starttime = GetTickCount(); // Add input and output buffers to PP queues. if (!PPAddInputBuffer(hPP, (UINT32) pInputFramePhysAddr)) { dwResult = TPR_FAIL; goto PP_CSC_YV12_RGB565Test_clean_up; } if (!PPAddOutputBuffer(hPP,(UINT32) pOutputFramePhysAddr)) { dwResult = TPR_FAIL; goto PP_CSC_YV12_RGB565Test_clean_up; } if (!PPWaitForNotBusy(hPP, FRAME_INTERRUPT)) { dwResult = TPR_FAIL; goto PP_CSC_YV12_RGB565Test_clean_up; } RETAILMSG(1, (TEXT("===========FLIP TIME: %dms====== \r\n"), GetTickCount()-starttime)); //----------------------------- // Stop PP //----------------------------- if (!PPStop(hPP)) { dwResult = TPR_FAIL; goto PP_CSC_YV12_RGB565Test_clean_up; } if (!PPClearBuffers(hPP)) { dwResult = TPR_FAIL; goto PP_CSC_YV12_RGB565Test_clean_up; } ShowRGBContent((UINT8 *) pOutputFrameVirtAddr, PP_TEST_FRAME_WIDTH, PP_TEST_FRAME_HEIGHT); iOption = MessageBox( NULL,TEXT("After CSC(YV12->RGB565). Is it correct?"),TEXT("Test result"),MB_YESNO ); if ( IDNO == iOption ) { dwResult = TPR_FAIL; } else { dwResult = TPR_PASS; } PP_CSC_YV12_RGB565Test_clean_up: if(NULL != pInputFrameVirtAddr) { FreePhysMem( pInputFrameVirtAddr ); pInputFrameVirtAddr = NULL; } if(NULL != pOutputFrameVirtAddr) { FreePhysMem( pOutputFrameVirtAddr ); pOutputFrameVirtAddr = NULL; } PPTestDeInit(); LogEntry(L"%d :Out %s Function \r\n",++abhineet,__WFUNCTION__); return dwResult; } The below is the flow for this function. It tells the start and end of this test. *** vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv *** TEST STARTING *** *** Test Name: PP CSC(YV12-RGB565) Test *** Test ID: 500 *** Library Path: pp_test.dll *** Command Line: *** Kernel Mode: Yes *** Random Seed: 24421 *** Thread Count: 0 *** vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv *******Abhineet-PPTEST : 338 : In ShellProc Function *******Abhineet-PPTEST : 339 : In Debug Function PP_TEST: ShellProc(SPM_BEGIN_TEST, ...) called *******Abhineet-PPTEST : 340 :Out Debug Function BEGIN TEST: "PP CSC(YV12-RGB565) Test", Threads=0, Seed=24421 *******Abhineet-PPTEST : 341 :Out ShellProc Function *******Abhineet-PPTEST : 342 : In PP_CSC_YV12_RGB565Test Function PP_CSC_YV12_RGB565Test *******Abhineet-PPTEST : 343 : In PPTestInit Function *******Abhineet-PPTEST : 344 : In GetPanelDimensions Function *******Abhineet-PPTEST : 345 :Out GetPanelDimensions Function GetPanelDimensions: width=1024 height=768 bpp=16 *******Abhineet-PPTEST : 346 :Out PPTestInit Function *******Abhineet-PPTEST : 347 : In ReadImage Function RELFSD: Opening file flags_112x160.yv12 from desktop *******Abhineet-PPTEST : 348 :Out ReadImage Function ===========FLIP TIME: 1ms====== *******Abhineet-PPTEST : 349 : In ShowRGBContent Function *******Abhineet-PPTEST : 350 :Out ShowRGBContent Function *******Abhineet-PPTEST : 351 : In PPTestDeInit Function *******Abhineet-PPTEST : 352 :Out PPTestDeInit Function *******Abhineet-PPTEST : 353 :Out PP_CSC_YV12_RGB565Test Function *******Abhineet-PPTEST : 354 : In DllMain Function *******Abhineet-PPTEST : 355 :Out DllMain Function *******Abhineet-PPTEST : 356 : In ShellProc Function *******Abhineet-PPTEST : 357 : In Debug Function PP_TEST: ShellProc(SPM_END_TEST, ...) called *******Abhineet-PPTEST : 358 :Out Debug Function END TEST: "PP CSC(YV12-RGB565) Test", PASSED, Time=6.007 *******Abhineet-PPTEST : 359 :Out ShellProc Function *** ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ *** TEST COMPLETED *** *** Test Name: PP CSC(YV12-RGB565) Test *** Test ID: 500 *** Library Path: pp_test.dll *** Command Line: *** Kernel Mode: Yes *** Result: Passed *** Random Seed: 24421 *** Thread Count: 1 *** Execution Time: 0:00:06.007 *** ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Please help me out to make changes to the above function for yuv444-rgb888.

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  • Silverlight for Windows Embedded tutorial (step 4)

    - by Valter Minute
    I’m back with my Silverlight for Windows Embedded tutorial. Sorry for the long delay between step 3 and step 4, the MVP summit and some work related issue prevented me from working on the tutorial during the last weeks. In our first,  second and third tutorial steps we implemented some very simple applications, just to understand the basic structure of a Silverlight for Windows Embedded application, learn how to handle events and how to operate on images. In this third step our sample application will be slightly more complicated, to introduce two new topics: list boxes and custom control. We will also learn how to create controls at runtime. I choose to explain those topics together and provide a sample a bit more complicated than usual just to start to give the feeling of how a “real” Silverlight for Windows Embedded application is organized. As usual we can start using Expression Blend to define our main page. In this case we will have a listbox and a textblock. Here’s the XAML code: <UserControl xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" x:Class="ListDemo.Page" Width="640" Height="480" x:Name="ListPage" xmlns:ListDemo="clr-namespace:ListDemo">   <Grid x:Name="LayoutRoot" Background="White"> <ListBox Margin="19,57,19,66" x:Name="FileList" SelectionChanged="Filelist_SelectionChanged"/> <TextBlock Height="35" Margin="19,8,19,0" VerticalAlignment="Top" TextWrapping="Wrap" x:Name="CurrentDir" Text="TextBlock" FontSize="20"/> </Grid> </UserControl> In our listbox we will load a list of directories, starting from the filesystem root (there are no drives in Windows CE, the filesystem has a single root named “\”). When the user clicks on an item inside the list, the corresponding directory path will be displayed in the TextBlock object and the subdirectories of the selected branch will be shown inside the list. As you can see we declared an event handler for the SelectionChanged event of our listbox. We also used a different font size for the TextBlock, to make it more readable. XAML and Expression Blend allow you to customize your UI pretty heavily, experiment with the tools and discover how you can completely change the aspect of your application without changing a single line of code! Inside our ListBox we want to insert the directory presenting a nice icon and their name, just like you are used to see them inside Windows 7 file explorer, for example. To get this we will define a user control. This is a custom object that will behave like “regular” Silverlight for Windows Embedded objects inside our application. First of all we have to define the look of our custom control, named DirectoryItem, using XAML: <UserControl xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" mc:Ignorable="d" x:Class="ListDemo.DirectoryItem" Width="500" Height="80">   <StackPanel x:Name="LayoutRoot" Orientation="Horizontal"> <Canvas Width="31.6667" Height="45.9583" Margin="10,10,10,10" RenderTransformOrigin="0.5,0.5"> <Canvas.RenderTransform> <TransformGroup> <ScaleTransform/> <SkewTransform/> <RotateTransform Angle="-31.27"/> <TranslateTransform/> </TransformGroup> </Canvas.RenderTransform> <Rectangle Width="31.6667" Height="45.8414" Canvas.Left="0" Canvas.Top="0.116943" Stretch="Fill"> <Rectangle.Fill> <LinearGradientBrush StartPoint="0.142631,0.75344" EndPoint="1.01886,0.75344"> <LinearGradientBrush.RelativeTransform> <TransformGroup> <SkewTransform CenterX="0.142631" CenterY="0.75344" AngleX="19.3128" AngleY="0"/> <RotateTransform CenterX="0.142631" CenterY="0.75344" Angle="-35.3436"/> </TransformGroup> </LinearGradientBrush.RelativeTransform> <LinearGradientBrush.GradientStops> <GradientStop Color="#FF7B6802" Offset="0"/> <GradientStop Color="#FFF3D42C" Offset="1"/> </LinearGradientBrush.GradientStops> </LinearGradientBrush> </Rectangle.Fill> </Rectangle> <Rectangle Width="29.8441" Height="43.1517" Canvas.Left="0.569519" Canvas.Top="1.05249" Stretch="Fill"> <Rectangle.Fill> <LinearGradientBrush StartPoint="0.142632,0.753441" EndPoint="1.01886,0.753441"> <LinearGradientBrush.RelativeTransform> <TransformGroup> <SkewTransform CenterX="0.142632" CenterY="0.753441" AngleX="19.3127" AngleY="0"/> <RotateTransform CenterX="0.142632" CenterY="0.753441" Angle="-35.3437"/> </TransformGroup> </LinearGradientBrush.RelativeTransform> <LinearGradientBrush.GradientStops> <GradientStop Color="#FFCDCDCD" Offset="0.0833333"/> <GradientStop Color="#FFFFFFFF" Offset="1"/> </LinearGradientBrush.GradientStops> </LinearGradientBrush> </Rectangle.Fill> </Rectangle> <Rectangle Width="29.8441" Height="43.1517" Canvas.Left="0.455627" Canvas.Top="2.28036" Stretch="Fill"> <Rectangle.Fill> <LinearGradientBrush StartPoint="0.142631,0.75344" EndPoint="1.01886,0.75344"> <LinearGradientBrush.RelativeTransform> <TransformGroup> <SkewTransform CenterX="0.142631" CenterY="0.75344" AngleX="19.3128" AngleY="0"/> <RotateTransform CenterX="0.142631" CenterY="0.75344" Angle="-35.3436"/> </TransformGroup> </LinearGradientBrush.RelativeTransform> <LinearGradientBrush.GradientStops> <GradientStop Color="#FFCDCDCD" Offset="0.0833333"/> <GradientStop Color="#FFFFFFFF" Offset="1"/> </LinearGradientBrush.GradientStops> </LinearGradientBrush> </Rectangle.Fill> </Rectangle> <Rectangle Width="29.8441" Height="43.1517" Canvas.Left="0.455627" Canvas.Top="1.34485" Stretch="Fill"> <Rectangle.Fill> <LinearGradientBrush StartPoint="0.142631,0.75344" EndPoint="1.01886,0.75344"> <LinearGradientBrush.RelativeTransform> <TransformGroup> <SkewTransform CenterX="0.142631" CenterY="0.75344" AngleX="19.3128" AngleY="0"/> <RotateTransform CenterX="0.142631" CenterY="0.75344" Angle="-35.3436"/> </TransformGroup> </LinearGradientBrush.RelativeTransform> <LinearGradientBrush.GradientStops> <GradientStop Color="#FFCDCDCD" Offset="0.0833333"/> <GradientStop Color="#FFFFFFFF" Offset="1"/> </LinearGradientBrush.GradientStops> </LinearGradientBrush> </Rectangle.Fill> </Rectangle> <Rectangle Width="26.4269" Height="45.8414" Canvas.Left="0.227798" Canvas.Top="0" Stretch="Fill"> <Rectangle.Fill> <LinearGradientBrush StartPoint="0.142631,0.75344" EndPoint="1.01886,0.75344"> <LinearGradientBrush.RelativeTransform> <TransformGroup> <SkewTransform CenterX="0.142631" CenterY="0.75344" AngleX="19.3127" AngleY="0"/> <RotateTransform CenterX="0.142631" CenterY="0.75344" Angle="-35.3436"/> </TransformGroup> </LinearGradientBrush.RelativeTransform> <LinearGradientBrush.GradientStops> <GradientStop Color="#FF7B6802" Offset="0"/> <GradientStop Color="#FFF3D42C" Offset="1"/> </LinearGradientBrush.GradientStops> </LinearGradientBrush> </Rectangle.Fill> </Rectangle> <Rectangle Width="1.25301" Height="45.8414" Canvas.Left="1.70862" Canvas.Top="0.116943" Stretch="Fill" Fill="#FFEBFF07"/> </Canvas> <TextBlock Height="80" x:Name="Name" Width="448" TextWrapping="Wrap" VerticalAlignment="Center" FontSize="24" Text="Directory"/> </StackPanel> </UserControl> As you can see, this XAML contains many graphic elements. Those elements are used to design the folder icon. The original drawing has been designed in Expression Design and then exported as XAML. In Silverlight for Windows Embedded you can use vector images. This means that your images will look good even when scaled or rotated. In our DirectoryItem custom control we have a TextBlock named Name, that will be used to display….(suspense)…. the directory name (I’m too lazy to invent fancy names for controls, and using “boring” intuitive names will make code more readable, I hope!). Now that we have some XAML code, we may execute XAML2CPP to generate part of the aplication code for us. We should then add references to our XAML2CPP generated resource file and include in our code and add a reference to the XAML runtime library to our sources file (you can follow the instruction of the first tutorial step to do that), To generate the code used in this tutorial you need XAML2CPP ver 1.0.1.0, that is downloadable here: http://geekswithblogs.net/WindowsEmbeddedCookbook/archive/2010/03/08/xaml2cpp-1.0.1.0.aspx We can now create our usual simple Win32 application inside Platform Builder, using the same step described in the first chapter of this tutorial (http://geekswithblogs.net/WindowsEmbeddedCookbook/archive/2009/10/01/silverlight-for-embedded-tutorial.aspx). We can declare a class for our main page, deriving it from the template that XAML2CPP generated for us: class ListPage : public TListPage<ListPage> { ... } We will see the ListPage class code in a short time, but before we will see the code of our DirectoryItem user control. This object will be used to populate our list, one item for each directory. To declare a user control things are a bit more complicated (but also in this case XAML2CPP will write most of the “boilerplate” code for use. To interact with a user control you should declare an interface. An interface defines the functions of a user control that can be called inside the application code. Our custom control is currently quite simple and we just need some member functions to store and retrieve a full pathname inside our control. The control will display just the last part of the path inside the control. An interface is declared as a C++ class that has only abstract virtual members. It should also have an UUID associated with it. UUID means Universal Unique IDentifier and it’s a 128 bit number that will identify our interface without the need of specifying its fully qualified name. UUIDs are used to identify COM interfaces and, as we discovered in chapter one, Silverlight for Windows Embedded is based on COM or, at least, provides a COM-like Application Programming Interface (API). Here’s the declaration of the DirectoryItem interface: class __declspec(novtable,uuid("{D38C66E5-2725-4111-B422-D75B32AA8702}")) IDirectoryItem : public IXRCustomUserControl { public:   virtual HRESULT SetFullPath(BSTR fullpath) = 0; virtual HRESULT GetFullPath(BSTR* retval) = 0; }; The interface is derived from IXRCustomControl, this will allow us to add our object to a XAML tree. It declares the two functions needed to set and get the full path, but don’t implement them. Implementation will be done inside the control class. The interface only defines the functions of our control class that are accessible from the outside. It’s a sort of “contract” between our control and the applications that will use it. We must support what’s inside the contract and the application code should know nothing else about our own control. To reference our interface we will use the UUID, to make code more readable we can declare a #define in this way: #define IID_IDirectoryItem __uuidof(IDirectoryItem) Silverlight for Windows Embedded objects (like COM objects) use a reference counting mechanism to handle object destruction. Every time you store a pointer to an object you should call its AddRef function and every time you no longer need that pointer you should call Release. The object keeps an internal counter, incremented for each AddRef and decremented on Release. When the counter reaches 0, the object is destroyed. Managing reference counting in our code can be quite complicated and, since we are lazy (I am, at least!), we will use a great feature of Silverlight for Windows Embedded: smart pointers.A smart pointer can be connected to a Silverlight for Windows Embedded object and manages its reference counting. To declare a smart pointer we must use the XRPtr template: typedef XRPtr<IDirectoryItem> IDirectoryItemPtr; Now that we have defined our interface, it’s time to implement our user control class. XAML2CPP has implemented a class for us, and we have only to derive our class from it, defining the main class and interface of our new custom control: class DirectoryItem : public DirectoryItemUserControlRegister<DirectoryItem,IDirectoryItem> { ... } XAML2CPP has generated some code for us to support the user control, we don’t have to mind too much about that code, since it will be generated (or written by hand, if you like) always in the same way, for every user control. But knowing how does this works “under the hood” is still useful to understand the architecture of Silverlight for Windows Embedded. Our base class declaration is a bit more complex than the one we used for a simple page in the previous chapters: template <class A,class B> class DirectoryItemUserControlRegister : public XRCustomUserControlImpl<A,B>,public TDirectoryItem<A,XAML2CPPUserControl> { ... } This class derives from the XAML2CPP generated template class, like the ListPage class, but it uses XAML2CPPUserControl for the implementation of some features. This class shares the same ancestor of XAML2CPPPage (base class for “regular” XAML pages), XAML2CPPBase, implements binding of member variables and event handlers but, instead of loading and creating its own XAML tree, it attaches to an existing one. The XAML tree (and UI) of our custom control is created and loaded by the XRCustomUserControlImpl class. This class is part of the Silverlight for Windows Embedded framework and implements most of the functions needed to build-up a custom control in Silverlight (the guys that developed Silverlight for Windows Embedded seem to care about lazy programmers!). We have just to initialize it, providing our class (DirectoryItem) and interface (IDirectoryItem). Our user control class has also a static member: protected:   static HINSTANCE hInstance; This is used to store the HINSTANCE of the modules that contain our user control class. I don’t like this implementation, but I can’t find a better one, so if somebody has good ideas about how to handle the HINSTANCE object, I’ll be happy to hear suggestions! It also implements two static members required by XRCustomUserControlImpl. The first one is used to load the XAML UI of our custom control: static HRESULT GetXamlSource(XRXamlSource* pXamlSource) { pXamlSource->SetResource(hInstance,TEXT("XAML"),IDR_XAML_DirectoryItem); return S_OK; }   It initializes a XRXamlSource object, connecting it to the XAML resource that XAML2CPP has included in our resource script. The other method is used to register our custom control, allowing Silverlight for Windows Embedded to create it when it load some XAML or when an application creates a new control at runtime (more about this later): static HRESULT Register() { return XRCustomUserControlImpl<A,B>::Register(__uuidof(B), L"DirectoryItem", L"clr-namespace:DirectoryItemNamespace"); } To register our control we should provide its interface UUID, the name of the corresponding element in the XAML tree and its current namespace (namespaces compatible with Silverlight must use the “clr-namespace” prefix. We may also register additional properties for our objects, allowing them to be loaded and saved inside XAML. In this case we have no permanent properties and the Register method will just register our control. An additional static method is implemented to allow easy registration of our custom control inside our application WinMain function: static HRESULT RegisterUserControl(HINSTANCE hInstance) { DirectoryItemUserControlRegister::hInstance=hInstance; return DirectoryItemUserControlRegister<A,B>::Register(); } Now our control is registered and we will be able to create it using the Silverlight for Windows Embedded runtime functions. But we need to bind our members and event handlers to have them available like we are used to do for other XAML2CPP generated objects. To bind events and members we need to implement the On_Loaded function: virtual HRESULT OnLoaded(__in IXRDependencyObject* pRoot) { HRESULT retcode; IXRApplicationPtr app; if (FAILED(retcode=GetXRApplicationInstance(&app))) return retcode; return ((A*)this)->Init(pRoot,hInstance,app); } This function will call the XAML2CPPUserControl::Init member that will connect the “root” member with the XAML sub tree that has been created for our control and then calls BindObjects and BindEvents to bind members and events to our code. Now we can go back to our application code (the code that you’ll have to actually write) to see the contents of our DirectoryItem class: class DirectoryItem : public DirectoryItemUserControlRegister<DirectoryItem,IDirectoryItem> { protected:   WCHAR fullpath[_MAX_PATH+1];   public:   DirectoryItem() { *fullpath=0; }   virtual HRESULT SetFullPath(BSTR fullpath) { wcscpy_s(this->fullpath,fullpath);   WCHAR* p=fullpath;   for(WCHAR*q=wcsstr(p,L"\\");q;p=q+1,q=wcsstr(p,L"\\")) ;   Name->SetText(p); return S_OK; }   virtual HRESULT GetFullPath(BSTR* retval) { *retval=SysAllocString(fullpath); return S_OK; } }; It’s pretty easy and contains a fullpath member (used to store that path of the directory connected with the user control) and the implementation of the two interface members that can be used to set and retrieve the path. The SetFullPath member parses the full path and displays just the last branch directory name inside the “Name” TextBlock object. As you can see, implementing a user control in Silverlight for Windows Embedded is not too complex and using XAML also for the UI of the control allows us to re-use the same mechanisms that we learnt and used in the previous steps of our tutorial. Now let’s see how the main page is managed by the ListPage class. class ListPage : public TListPage<ListPage> { protected:   // current path TCHAR curpath[_MAX_PATH+1]; It has a member named “curpath” that is used to store the current directory. It’s initialized inside the constructor: ListPage() { *curpath=0; } And it’s value is displayed inside the “CurrentDir” TextBlock inside the initialization function: virtual HRESULT Init(HINSTANCE hInstance,IXRApplication* app) { HRESULT retcode;   if (FAILED(retcode=TListPage<ListPage>::Init(hInstance,app))) return retcode;   CurrentDir->SetText(L"\\"); return S_OK; } The FillFileList function is used to enumerate subdirectories of the current dir and add entries for each one inside the list box that fills most of the client area of our main page: HRESULT FillFileList() { HRESULT retcode; IXRItemCollectionPtr items; IXRApplicationPtr app;   if (FAILED(retcode=GetXRApplicationInstance(&app))) return retcode; // retrieves the items contained in the listbox if (FAILED(retcode=FileList->GetItems(&items))) return retcode;   // clears the list if (FAILED(retcode=items->Clear())) return retcode;   // enumerates files and directory in the current path WCHAR filemask[_MAX_PATH+1];   wcscpy_s(filemask,curpath); wcscat_s(filemask,L"\\*.*");   WIN32_FIND_DATA finddata; HANDLE findhandle;   findhandle=FindFirstFile(filemask,&finddata);   // the directory is empty? if (findhandle==INVALID_HANDLE_VALUE) return S_OK;   do { if (finddata.dwFileAttributes&=FILE_ATTRIBUTE_DIRECTORY) { IXRListBoxItemPtr listboxitem;   // add a new item to the listbox if (FAILED(retcode=app->CreateObject(IID_IXRListBoxItem,&listboxitem))) { FindClose(findhandle); return retcode; }   if (FAILED(retcode=items->Add(listboxitem,NULL))) { FindClose(findhandle); return retcode; }   IDirectoryItemPtr directoryitem;   if (FAILED(retcode=app->CreateObject(IID_IDirectoryItem,&directoryitem))) { FindClose(findhandle); return retcode; }   WCHAR fullpath[_MAX_PATH+1];   wcscpy_s(fullpath,curpath); wcscat_s(fullpath,L"\\"); wcscat_s(fullpath,finddata.cFileName);   if (FAILED(retcode=directoryitem->SetFullPath(fullpath))) { FindClose(findhandle); return retcode; }   XAML2CPPXRValue value((IXRDependencyObject*)directoryitem);   if (FAILED(retcode=listboxitem->SetContent(&value))) { FindClose(findhandle); return retcode; } } } while (FindNextFile(findhandle,&finddata));   FindClose(findhandle); return S_OK; } This functions retrieve a pointer to the collection of the items contained in the directory listbox. The IXRItemCollection interface is used by listboxes and comboboxes and allow you to clear the list (using Clear(), as our function does at the beginning) and change its contents by adding and removing elements. This function uses the FindFirstFile/FindNextFile functions to enumerate all the objects inside our current directory and for each subdirectory creates a IXRListBoxItem object. You can insert any kind of control inside a list box, you don’t need a IXRListBoxItem, but using it will allow you to handle the selected state of an item, highlighting it inside the list. The function creates a list box item using the CreateObject function of XRApplication. The same function is then used to create an instance of our custom control. The function returns a pointer to the control IDirectoryItem interface and we can use it to store the directory full path inside the object and add it as content of the IXRListBox item object, adding it to the listbox contents. The listbox generates an event (SelectionChanged) each time the user clicks on one of the items contained in the listbox. We implement an event handler for that event and use it to change our current directory and repopulate the listbox. The current directory full path will be displayed in the TextBlock: HRESULT Filelist_SelectionChanged(IXRDependencyObject* source,XRSelectionChangedEventArgs* args) { HRESULT retcode;   IXRListBoxItemPtr listboxitem;   if (!args->pAddedItem) return S_OK;   if (FAILED(retcode=args->pAddedItem->QueryInterface(IID_IXRListBoxItem,(void**)&listboxitem))) return retcode;   XRValue content; if (FAILED(retcode=listboxitem->GetContent(&content))) return retcode;   if (content.vType!=VTYPE_OBJECT) return E_FAIL;   IDirectoryItemPtr directoryitem;   if (FAILED(retcode=content.pObjectVal->QueryInterface(IID_IDirectoryItem,(void**)&directoryitem))) return retcode;   content.pObjectVal->Release(); content.pObjectVal=NULL;   BSTR fullpath=NULL;   if (FAILED(retcode=directoryitem->GetFullPath(&fullpath))) return retcode;   CurrentDir->SetText(fullpath);   wcscpy_s(curpath,fullpath); FillFileList(); SysFreeString(fullpath);     return S_OK; } }; The function uses the pAddedItem member of the XRSelectionChangedEventArgs object to retrieve the currently selected item, converts it to a IXRListBoxItem interface using QueryInterface, and then retrives its contents (IDirectoryItem object). Using the GetFullPath method we can get the full path of our selected directory and assing it to the curdir member. A call to FillFileList will update the listbox contents, displaying the list of subdirectories of the selected folder. To build our sample we just need to add code to our WinMain function: int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPTSTR lpCmdLine, int nCmdShow) { if (!XamlRuntimeInitialize()) return -1;   HRESULT retcode;   IXRApplicationPtr app; if (FAILED(retcode=GetXRApplicationInstance(&app))) return -1;   if (FAILED(retcode=DirectoryItem::RegisterUserControl(hInstance))) return retcode;   ListPage page;   if (FAILED(page.Init(hInstance,app))) return -1;   page.FillFileList();   UINT exitcode;   if (FAILED(page.GetVisualHost()->StartDialog(&exitcode))) return -1;   return 0; } This code is very similar to the one of the WinMains of our previous samples. The main differences are that we register our custom control (you should do that as soon as you have initialized the XAML runtime) and call FillFileList after the initialization of our ListPage object to load the contents of the root folder of our device inside the listbox. As usual you can download the full sample source code from here: http://cid-9b7b0aefe3514dc5.skydrive.live.com/self.aspx/.Public/ListBoxTest.zip

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  • iPhone SDK Tableview Datasource singleton error

    - by mrburns05
    I basically followed apple "TheElements" sample and changed "PeriodicElements" .h & .m to my own "SortedItems" .h & .m During compile I get this error: "Undefined symbols: "_OBJC_CLASS_$_SortedItems", referenced from: __objc_classrefs__DATA@0 in SortedByNameTableDataSource.o ld: symbol(s) not found collect2: ld returned 1 exit status " here is my SortedItems.m file #import "SortedItems.h" #import "item.h" #import "MyAppDelegate.h" @interface SortedItems(mymethods) // these are private methods that outside classes need not use - (void)presortItemsByPhysicalState; - (void)presortItemInitialLetterIndexes; - (void)presortItemNamesForInitialLetter:(NSString *)aKey; - (void)presortItemsWithPhysicalState:(NSString *)state; - (NSArray *)presortItemsByNumber; - (NSArray *)presortItemsBySymbol; - (void)setupItemsArray; @end @implementation SortedItems @synthesize statesDictionary; @synthesize itemsDictionary; @synthesize nameIndexesDictionary; @synthesize itemNameIndexArray; @synthesize itemsSortedByNumber; @synthesize itemsSortedBySymbol; @synthesize itemPhysicalStatesArray; static SortedItems *sharedSortedItemsInstance = nil; + (SortedItems*)sharedSortedItems { @synchronized(self) { if (sharedSortedItemsInstance == nil) { [[self alloc] init]; // assignment not done here } } return sharedSortedItemsInstance; // note: Xcode (3.2) static analyzer will report this singleton as a false positive // '(Potential leak of an object allocated') } + (id)allocWithZone:(NSZone *)zone { @synchronized(self) { if (sharedSortedItemsInstance == nil) { sharedSortedItemsInstance = [super allocWithZone:zone]; return sharedSortedItemsInstance; // assignment and return on first allocation } } return nil; //on subsequent allocation attempts return nil } - (id)copyWithZone:(NSZone *)zone { return self; } - (id)retain { return self; } - (unsigned)retainCount { return UINT_MAX; //denotes an object that cannot be released } - (void)release { //do nothing } - (id)autorelease { return self; } // setup the data collection - init { if (self = [super init]) { [self setupItemsArray]; } return self; } - (void)setupItemsArray { NSDictionary *eachItem; // create dictionaries that contain the arrays of Item data indexed by // name self.itemsDictionary = [NSMutableDictionary dictionary]; // physical state self.statesDictionary = [NSMutableDictionary dictionary]; // unique first characters (for the Name index table) self.nameIndexesDictionary = [NSMutableDictionary dictionary]; // create empty array entries in the states Dictionary or each physical state [statesDictionary setObject:[NSMutableArray array] forKey:@"Solid"]; [statesDictionary setObject:[NSMutableArray array] forKey:@"Liquid"]; [statesDictionary setObject:[NSMutableArray array] forKey:@"Gas"]; [statesDictionary setObject:[NSMutableArray array] forKey:@"Artificial"]; MyAppDelegate *ad = (MyAppDelegate *)[[UIApplication sharedApplication]delegate]; NSMutableArray *rawItemsArray = [[NSMutableArray alloc] init]; [rawItemsArray addObjectsFromArray:ad.items]; // iterate over the values in the raw Items dictionary for (eachItem in rawItemsArray) { // create an atomic Item instance for each Item *anItem = [[Item alloc] initWithDictionary:eachItem]; // store that item in the Items dictionary with the name as the key [itemsDictionary setObject:anItem forKey:anItem.title]; // add that Item to the appropriate array in the physical state dictionary [[statesDictionary objectForKey:anItem.acct] addObject:anItem]; // get the Item's initial letter NSString *firstLetter = [anItem.title substringToIndex:1]; NSMutableArray *existingArray; // if an array already exists in the name index dictionary // simply add the Item to it, otherwise create an array // and add it to the name index dictionary with the letter as the key if (existingArray = [nameIndexesDictionary valueForKey:firstLetter]) { [existingArray addObject:anItem]; } else { NSMutableArray *tempArray = [NSMutableArray array]; [nameIndexesDictionary setObject:tempArray forKey:firstLetter]; [tempArray addObject:anItem]; } // release the Item, it is held by the various collections [anItem release]; } // release the raw Item data [rawItemsArray release]; // create the dictionary containing the possible Item states // and presort the states data self.itemPhysicalStatesArray = [NSArray arrayWithObjects:@"something",@"somethingElse",@"whatever",@"stuff",nil]; [self presortItemsByPhysicalState]; // presort the dictionaries now // this could be done the first time they are requested instead [self presortItemInitialLetterIndexes]; self.itemsSortedByNumber = [self presortItemsByNumber]; self.itemsSortedBySymbol = [self presortItemsBySymbol]; } // return the array of Items for the requested physical state - (NSArray *)itemsWithPhysicalState:(NSString*)aState { return [statesDictionary objectForKey:aState]; } // presort each of the arrays for the physical states - (void)presortItemsByPhysicalState { for (NSString *stateKey in itemPhysicalStatesArray) { [self presortItemsWithPhysicalState:stateKey]; } } - (void)presortItemsWithPhysicalState:(NSString *)state { NSSortDescriptor *nameDescriptor = [[NSSortDescriptor alloc] initWithKey:@"title" ascending:YES selector:@selector(localizedCaseInsensitiveCompare:)] ; NSArray *descriptors = [NSArray arrayWithObject:nameDescriptor]; [[statesDictionary objectForKey:state] sortUsingDescriptors:descriptors]; [nameDescriptor release]; } // return an array of Items for an initial letter (ie A, B, C, ...) - (NSArray *)itemsWithInitialLetter:(NSString*)aKey { return [nameIndexesDictionary objectForKey:aKey]; } // presort the name index arrays so the items are in the correct order - (void)presortItemsInitialLetterIndexes { self.itemNameIndexArray = [[nameIndexesDictionary allKeys] sortedArrayUsingSelector:@selector(localizedCaseInsensitiveCompare:)]; for (NSString *eachNameIndex in itemNameIndexArray) { [self presortItemNamesForInitialLetter:eachNameIndex]; } } - (void)presortItemNamesForInitialLetter:(NSString *)aKey { NSSortDescriptor *nameDescriptor = [[NSSortDescriptor alloc] initWithKey:@"title" ascending:YES selector:@selector(localizedCaseInsensitiveCompare:)] ; NSArray *descriptors = [NSArray arrayWithObject:nameDescriptor]; [[nameIndexesDictionary objectForKey:aKey] sortUsingDescriptors:descriptors]; [nameDescriptor release]; } // presort the ItemsSortedByNumber array - (NSArray *)presortItemsByNumber { NSSortDescriptor *nameDescriptor = [[NSSortDescriptor alloc] initWithKey:@"acct" ascending:YES selector:@selector(compare:)] ; NSArray *descriptors = [NSArray arrayWithObject:nameDescriptor]; NSArray *sortedItems = [[itemsDictionary allValues] sortedArrayUsingDescriptors:descriptors]; [nameDescriptor release]; return sortedItems; } // presort the itemsSortedBySymbol array - (NSArray *)presortItemsBySymbol { NSSortDescriptor *symbolDescriptor = [[NSSortDescriptor alloc] initWithKey:@"title" ascending:YES selector:@selector(localizedCaseInsensitiveCompare:)] ; NSArray *descriptors = [NSArray arrayWithObject:symbolDescriptor]; NSArray *sortedItems = [[itemsDictionary allValues] sortedArrayUsingDescriptors:descriptors]; [symbolDescriptor release]; return sortedItems; } @end I followed the sample exactly - don't know where I went wrong. Here is my "SortedByNameTableDataSource.m" #import "SortedByNameTableDataSource.h" #import "SortedItems.h" #import "Item.h" #import "ItemCell.h" #import "GradientView.h" #import "UIColor-Expanded.h" #import "MyAppDelegate.h" @implementation SortedByNameTableDataSource - (NSString *)title { return @"Title"; } - (UITableViewStyle)tableViewStyle { return UITableViewStylePlain; }; // return the atomic element at the index - (Item *)itemForIndexPath:(NSIndexPath *)indexPath { return [[[SortedItems sharedSortedItems] itemsWithInitialLetter:[[[SortedItems sharedSortedItems] itemNameIndexArray] objectAtIndex:indexPath.section]] objectAtIndex:indexPath.row]; } // UITableViewDataSource methods - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { static NSString *MyIdentifier = @"ItemCell"; ItemCell *itemCell = (ItemCell *)[tableView dequeueReusableCellWithIdentifier:MyIdentifier]; if (itemCell == nil) { itemCell = [[[ItemCell alloc] initWithFrame:CGRectZero reuseIdentifier:MyIdentifier] autorelease]; itemCell = CGRectMake(0.0, 0.0, 320.0, ROW_HEIGHT); itemCell.backgroundView = [[[GradientView alloc] init] autorelease]; } itemCell.todo = [self itemForIndexPath:indexPath]; return itemCell; } - (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView { // this table has multiple sections. One for each unique character that an element begins with // [A,B,C,D,E,F,G,H,I,K,L,M,N,O,P,R,S,T,U,V,X,Y,Z] // return the count of that array return [[[SortedItems sharedSortedItems] itemNameIndexArray] count]; } - (NSArray *)sectionIndexTitlesForTableView:(UITableView *)tableView { // returns the array of section titles. There is one entry for each unique character that an element begins with // [A,B,C,D,E,F,G,H,I,K,L,M,N,O,P,R,S,T,U,V,X,Y,Z] return [[SortedItems sharedSortedItems] itemNameIndexArray]; } - (NSInteger)tableView:(UITableView *)tableView sectionForSectionIndexTitle:(NSString *)title atIndex:(NSInteger)index { return index; } - (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section { // the section represents the initial letter of the element // return that letter NSString *initialLetter = [[[SortedItems sharedSortedItems] itemNameIndexArray] objectAtIndex:section]; // get the array of elements that begin with that letter NSArray *itemsWithInitialLetter = [[SortedItems sharedSortedItems] itemsWithInitialLetter:initialLetter]; // return the count return [itemsWithInitialLetter count]; } - (NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section { // this table has multiple sections. One for each unique character that an element begins with // [A,B,C,D,E,F,G,H,I,K,L,M,N,O,P,R,S,T,U,V,X,Y,Z] // return the letter that represents the requested section // this is actually a delegate method, but we forward the request to the datasource in the view controller return [[[SortedItems sharedSortedItems] itemNameIndexArray] objectAtIndex:section]; } @end

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  • Trouble with a query

    - by Mark Allison
    Hi there, I'm having trouble with a query in SQL Server 2008 on some forex trading data. I have a trades table and an orders table. A trade needs to comprise of 2 or more orders. DDL schema and sample data below. What I want to do is write a query that shows the profit/loss in pips for each trade. A pip is 1/1000th of a currency. So the difference between USD 1.3441 and 1.3442 is 1 pip in forex-speak. A trade usually has one entry order and multiple exit orders. So for example if I buy 3 lots of the currency pair GBP/USD at the exchange rate of 1.6100 and then sell 1 lot at 1.6150, 1 lot at 1.6200 and 1 lot at 1.6250 then the profit is (1.6150 - 1.6100) + (1.6200 - 1.6100) + (1.6250 - 1.6100), or 50 + 100 + 150 = 300 pips profit. The trade could also go the other way (Shorting). For example the currency pair can be sold first before it's bought back later at a cheaper price. I would like a query that returns the following: tradeId, currencyPair, profitInPips It seems like a pretty straightforward query, but it's eluding me right now. Here's my DDL and sample data: CREATE TABLE [dbo].[trades]( [tradeId] [int] IDENTITY(1,1) NOT NULL, [currencyPair] [char](6) NOT NULL, CONSTRAINT [PK_trades] PRIMARY KEY CLUSTERED ( [tradeId] ASC )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] ) ON [PRIMARY] GO SET ANSI_PADDING OFF GO SET IDENTITY_INSERT [dbo].[trades] ON INSERT [dbo].[trades] ([tradeId], [currencyPair]) VALUES (1, N'GBPUSD') INSERT [dbo].[trades] ([tradeId], [currencyPair]) VALUES (2, N'GBPUSD') INSERT [dbo].[trades] ([tradeId], [currencyPair]) VALUES (3, N'GBPUSD') INSERT [dbo].[trades] ([tradeId], [currencyPair]) VALUES (4, N'GBPUSD') INSERT [dbo].[trades] ([tradeId], [currencyPair]) VALUES (5, N'GBPUSD') INSERT [dbo].[trades] ([tradeId], [currencyPair]) VALUES (6, N'GBPUSD') INSERT [dbo].[trades] ([tradeId], [currencyPair]) VALUES (7, N'GBPUSD') INSERT [dbo].[trades] ([tradeId], [currencyPair]) VALUES (8, N'GBPUSD') INSERT [dbo].[trades] ([tradeId], [currencyPair]) VALUES (9, N'GBPUSD') INSERT [dbo].[trades] ([tradeId], [currencyPair]) VALUES (10, N'GBPUSD') SET IDENTITY_INSERT [dbo].[trades] OFF GO CREATE TABLE [dbo].[orders]( [orderId] [int] IDENTITY(1,1) NOT NULL, [tradeId] [int] NOT NULL, [amount] [decimal](18, 1) NOT NULL, [buySell] [char](1) NOT NULL, [rate] [decimal](18, 6) NOT NULL, [orderDateTime] [datetime] NOT NULL, CONSTRAINT [PK_orders] PRIMARY KEY CLUSTERED ( [orderId] ASC )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] ) ON [PRIMARY] GO SET ANSI_PADDING OFF GO SET IDENTITY_INSERT [dbo].[orders] ON INSERT [dbo].[orders] ([orderId], [tradeId], [amount], [buySell], [rate], [orderDateTime]) VALUES (1, 1, CAST(3.0 AS Decimal(18, 1)), N'S', CAST(1.606500 AS Decimal(18, 6)), CAST(0x00009CF40083D600 AS DateTime)) INSERT [dbo].[orders] ([orderId], [tradeId], [amount], [buySell], [rate], [orderDateTime]) VALUES (2, 1, CAST(3.0 AS Decimal(18, 1)), N'B', CAST(1.615500 AS Decimal(18, 6)), CAST(0x00009CF400A4CB80 AS DateTime)) INSERT [dbo].[orders] ([orderId], [tradeId], [amount], [buySell], [rate], [orderDateTime]) VALUES (3, 2, CAST(3.0 AS Decimal(18, 1)), N'S', CAST(1.608000 AS Decimal(18, 6)), CAST(0x00009CF500000000 AS DateTime)) INSERT [dbo].[orders] ([orderId], [tradeId], [amount], [buySell], [rate], [orderDateTime]) VALUES (4, 2, CAST(1.0 AS Decimal(18, 1)), N'B', CAST(1.603000 AS Decimal(18, 6)), CAST(0x00009CF50083D600 AS DateTime)) INSERT [dbo].[orders] ([orderId], [tradeId], [amount], [buySell], [rate], [orderDateTime]) VALUES (5, 2, CAST(2.0 AS Decimal(18, 1)), N'B', CAST(1.605500 AS Decimal(18, 6)), CAST(0x00009CF50107AC00 AS DateTime)) INSERT [dbo].[orders] ([orderId], [tradeId], [amount], [buySell], [rate], [orderDateTime]) VALUES (6, 3, CAST(3.0 AS Decimal(18, 1)), N'S', CAST(1.595500 AS Decimal(18, 6)), CAST(0x00009CF70083D600 AS DateTime)) INSERT [dbo].[orders] ([orderId], [tradeId], [amount], [buySell], [rate], [orderDateTime]) VALUES (7, 3, CAST(1.0 AS Decimal(18, 1)), N'B', CAST(1.590500 AS Decimal(18, 6)), CAST(0x00009CF700C5C100 AS DateTime)) INSERT [dbo].[orders] ([orderId], [tradeId], [amount], [buySell], [rate], [orderDateTime]) VALUES (8, 3, CAST(2.0 AS Decimal(18, 1)), N'B', CAST(1.594500 AS Decimal(18, 6)), CAST(0x00009CF701499700 AS DateTime)) INSERT [dbo].[orders] ([orderId], [tradeId], [amount], [buySell], [rate], [orderDateTime]) VALUES (9, 4, CAST(3.0 AS Decimal(18, 1)), N'B', CAST(1.611000 AS Decimal(18, 6)), CAST(0x00009CFB0083D600 AS DateTime)) INSERT [dbo].[orders] ([orderId], [tradeId], [amount], [buySell], [rate], [orderDateTime]) VALUES (10, 4, CAST(1.0 AS Decimal(18, 1)), N'S', CAST(1.616000 AS Decimal(18, 6)), CAST(0x00009CFB00A4CB80 AS DateTime)) INSERT [dbo].[orders] ([orderId], [tradeId], [amount], [buySell], [rate], [orderDateTime]) VALUES (11, 4, CAST(2.0 AS Decimal(18, 1)), N'S', CAST(1.611500 AS Decimal(18, 6)), CAST(0x00009CFB0107AC00 AS DateTime)) INSERT [dbo].[orders] ([orderId], [tradeId], [amount], [buySell], [rate], [orderDateTime]) VALUES (12, 5, CAST(3.0 AS Decimal(18, 1)), N'B', CAST(1.613000 AS Decimal(18, 6)), CAST(0x00009CFC0083D600 AS DateTime)) INSERT [dbo].[orders] ([orderId], [tradeId], [amount], [buySell], [rate], [orderDateTime]) VALUES (13, 5, CAST(1.0 AS Decimal(18, 1)), N'S', CAST(1.618000 AS Decimal(18, 6)), CAST(0x00009CFC0107AC00 AS DateTime)) INSERT [dbo].[orders] ([orderId], [tradeId], [amount], [buySell], [rate], [orderDateTime]) VALUES (14, 5, CAST(1.0 AS Decimal(18, 1)), N'S', CAST(1.623000 AS Decimal(18, 6)), CAST(0x00009CFC0083D600 AS DateTime)) INSERT [dbo].[orders] ([orderId], [tradeId], [amount], [buySell], [rate], [orderDateTime]) VALUES (15, 5, CAST(1.0 AS Decimal(18, 1)), N'S', CAST(1.628000 AS Decimal(18, 6)), CAST(0x00009CFD00C5C100 AS DateTime)) INSERT [dbo].[orders] ([orderId], [tradeId], [amount], [buySell], [rate], [orderDateTime]) VALUES (16, 6, CAST(3.0 AS Decimal(18, 1)), N'B', CAST(1.632000 AS Decimal(18, 6)), CAST(0x00009D020083D600 AS DateTime)) INSERT [dbo].[orders] ([orderId], [tradeId], [amount], [buySell], [rate], [orderDateTime]) VALUES (17, 6, CAST(1.0 AS Decimal(18, 1)), N'S', CAST(1.637000 AS Decimal(18, 6)), CAST(0x00009D0200A4CB80 AS DateTime)) INSERT [dbo].[orders] ([orderId], [tradeId], [amount], [buySell], [rate], [orderDateTime]) VALUES (18, 6, CAST(2.0 AS Decimal(18, 1)), N'S', CAST(1.630000 AS Decimal(18, 6)), CAST(0x00009D0200C5C100 AS DateTime)) INSERT [dbo].[orders] ([orderId], [tradeId], [amount], [buySell], [rate], [orderDateTime]) VALUES (19, 7, CAST(3.0 AS Decimal(18, 1)), N'B', CAST(1.634500 AS Decimal(18, 6)), CAST(0x00009D0201499700 AS DateTime)) INSERT [dbo].[orders] ([orderId], [tradeId], [amount], [buySell], [rate], [orderDateTime]) VALUES (20, 7, CAST(1.0 AS Decimal(18, 1)), N'S', CAST(1.639500 AS Decimal(18, 6)), CAST(0x00009D0300000000 AS DateTime)) INSERT [dbo].[orders] ([orderId], [tradeId], [amount], [buySell], [rate], [orderDateTime]) VALUES (21, 7, CAST(1.0 AS Decimal(18, 1)), N'S', CAST(1.644500 AS Decimal(18, 6)), CAST(0x00009D030083D600 AS DateTime)) INSERT [dbo].[orders] ([orderId], [tradeId], [amount], [buySell], [rate], [orderDateTime]) VALUES (22, 7, CAST(1.0 AS Decimal(18, 1)), N'S', CAST(1.637500 AS Decimal(18, 6)), CAST(0x00009D0300C5C100 AS DateTime)) INSERT [dbo].[orders] ([orderId], [tradeId], [amount], [buySell], [rate], [orderDateTime]) VALUES (23, 8, CAST(3.0 AS Decimal(18, 1)), N'S', CAST(1.625000 AS Decimal(18, 6)), CAST(0x00009D0400C5C100 AS DateTime)) INSERT [dbo].[orders] ([orderId], [tradeId], [amount], [buySell], [rate], [orderDateTime]) VALUES (24, 8, CAST(1.0 AS Decimal(18, 1)), N'B', CAST(1.620000 AS Decimal(18, 6)), CAST(0x00009D050083D600 AS DateTime)) INSERT [dbo].[orders] ([orderId], [tradeId], [amount], [buySell], [rate], [orderDateTime]) VALUES (25, 8, CAST(1.0 AS Decimal(18, 1)), N'B', CAST(1.615000 AS Decimal(18, 6)), CAST(0x00009D0500A4CB80 AS DateTime)) INSERT [dbo].[orders] ([orderId], [tradeId], [amount], [buySell], [rate], [orderDateTime]) VALUES (26, 8, CAST(1.0 AS Decimal(18, 1)), N'S', CAST(1.623000 AS Decimal(18, 6)), CAST(0x00009D050107AC00 AS DateTime)) INSERT [dbo].[orders] ([orderId], [tradeId], [amount], [buySell], [rate], [orderDateTime]) VALUES (27, 9, CAST(3.0 AS Decimal(18, 1)), N'S', CAST(1.618000 AS Decimal(18, 6)), CAST(0x00009D0600C5C100 AS DateTime)) INSERT [dbo].[orders] ([orderId], [tradeId], [amount], [buySell], [rate], [orderDateTime]) VALUES (28, 9, CAST(1.0 AS Decimal(18, 1)), N'B', CAST(1.613000 AS Decimal(18, 6)), CAST(0x00009D0600D63BC0 AS DateTime)) INSERT [dbo].[orders] ([orderId], [tradeId], [amount], [buySell], [rate], [orderDateTime]) VALUES (29, 9, CAST(1.0 AS Decimal(18, 1)), N'B', CAST(1.608000 AS Decimal(18, 6)), CAST(0x00009D0600E6B680 AS DateTime)) INSERT [dbo].[orders] ([orderId], [tradeId], [amount], [buySell], [rate], [orderDateTime]) VALUES (30, 9, CAST(1.0 AS Decimal(18, 1)), N'B', CAST(1.613300 AS Decimal(18, 6)), CAST(0x00009D0601391C40 AS DateTime)) INSERT [dbo].[orders] ([orderId], [tradeId], [amount], [buySell], [rate], [orderDateTime]) VALUES (31, 10, CAST(3.0 AS Decimal(18, 1)), N'B', CAST(1.614500 AS Decimal(18, 6)), CAST(0x00009D090083D600 AS DateTime)) INSERT [dbo].[orders] ([orderId], [tradeId], [amount], [buySell], [rate], [orderDateTime]) VALUES (32, 10, CAST(1.0 AS Decimal(18, 1)), N'S', CAST(1.619500 AS Decimal(18, 6)), CAST(0x00009D090107AC00 AS DateTime)) INSERT [dbo].[orders] ([orderId], [tradeId], [amount], [buySell], [rate], [orderDateTime]) VALUES (33, 10, CAST(1.0 AS Decimal(18, 1)), N'S', CAST(1.624500 AS Decimal(18, 6)), CAST(0x00009D0901499700 AS DateTime)) INSERT [dbo].[orders] ([orderId], [tradeId], [amount], [buySell], [rate], [orderDateTime]) VALUES (34, 10, CAST(1.0 AS Decimal(18, 1)), N'S', CAST(1.619000 AS Decimal(18, 6)), CAST(0x00009D0A0083D600 AS DateTime)) SET IDENTITY_INSERT [dbo].[orders] OFF /****** Object: ForeignKey [FK_orders_trades] Script Date: 04/02/2010 15:05:31 ******/ ALTER TABLE [dbo].[orders] WITH CHECK ADD CONSTRAINT [FK_orders_trades] FOREIGN KEY([tradeId]) REFERENCES [dbo].[trades] ([tradeId]) GO ALTER TABLE [dbo].[orders] CHECK CONSTRAINT [FK_orders_trades] GO Thanks in advance for any help!

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  • RESTful services architecture question

    - by abovesun
    This is question more about service architecture strategy, we are building big web system based on rest services on back end. And we are currently trying to build some standard internal to follow while developing rest services. Some queries returns list of entities, for example lets consider we have image galleries retrieving service: /gell_all_galeries, returning next response: <galleries> <gallery> <id>some_gallery_id</id> <name>my photos</name> <photos> <photo> <id>123</id> <name>my photo</name> <location>http://mysite/photo/show/123</location> ...... <author> <id>some_id</id> <name>some name</name> ....... <author> </photo> <photo> ..... </photo> <photo> ..... </photo> <photo> ..... </photo> <photo> ..... </photo> </photos> </gallery> <gallery> .... </gallery> <gallery> .... </gallery> <gallery> .... </gallery> <gallery> .... </gallery> </galleries> As you see here, response quite big and heavy, and not always we need such deep info level. Usual solution is to use or http://ru.wikipedia.org/wiki/Atom elements for each gallery instead of full gallery data: <galleries> <gallery> <id>some_gallery_id</id> <link href="http://mysite/gallery/some_gallery_id"/> </gallery> <gallery> <id>second_gallery_id</id> <link href="http://mysite/gallery/second_gallery_id"/> </gallery> <gallery> .... </gallery> <gallery> .... </gallery> <gallery> .... </gallery> <gallery> .... </gallery> </galleries> The first question, is next: maybe instead we shouldn't even use and types, and just use generic and for all resources that return list objects: <list> <item><link href="http://mysite/gallery/some_gallery_id"/></item> <item><link href="http://mysite/gallery/other_gallery_id"/></item> <item>....</item> </list> And the second question, after user try to retrieve info about some concrete gallery, he'll use for example http://mysite/gallery/some_gallery_id link, what should he see as results? Should it be: <gallery> <id>some_gallery_id</id> <name>my photos</name> <photos> <photo> <id>123</id> <name>my photo</name> <location>http://mysite/photo/show/123</location> ...... <author> <id>some_id</id> <name>some name</name> ....... <author> </photo> <photo> ..... </photo> <photo> ..... </photo> <photo> ..... </photo> <photo> ..... </photo> </photos> </gallery> or : <gallery> <id>some_gallery_id</id> <name>my photos</name> <photos> <photo><link href="http://mysite/photo/11111"/></photo> <photo><link href="http://mysite/photo/22222"/></photo> <photo><link href="http://mysite/photo/33333"/> </photo> <photo> ..... </photo> </photos> </gallery> or <gallery> <id>some_gallery_id</id> <name>my photos</name> <photos> <photo> <link href="http://mysite/photo/11111"/> <author> <link href="http://mysite/author/11111"/> </author> </photo> <photo> <link href="http://mysite/photo/22222"/> <author> <link href="http://mysite/author/11111"/> </author> </photo> <photo> <link href="http://mysite/photo/33333"/> <author> <link href="http://mysite/author/11111"/> </author> </photo> <photo> ..... </photo> </photos> </gallery> I mean if we use link instead of full object info, how deep we should go there? Should I show an author inside photo and so on. Probably my question ambiguous, but what I'm trying to do is create general strategy in such cases for all team members to follow in future.

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  • Spring security - Reach users ID without passing it through every controller

    - by nilsi
    I have a design issue that I don't know how to solve. I'm using Spring 3.2.4 and Spring security 3.1.4. I have a Account table in my database that looks like this: create table Account (id identity, username varchar unique, password varchar not null, firstName varchar not null, lastName varchar not null, university varchar not null, primary key (id)); Until recently my username was just only a username but I changed it to be the email address instead since many users want to login with that instead. I have a header that I include on all my pages which got a link to the users profile like this: <a href="/project/users/<%= request.getUserPrincipal().getName()%>" class="navbar-link"><strong><%= request.getUserPrincipal().getName()%></strong></a> The problem is that <%= request.getUserPrincipal().getName()%> returns the email now, I don't want to link the user's with thier emails. Instead I want to use the id every user have to link to the profile. How do I reach the users id's from every page? I have been thinking of two solutions but I'm not sure: Change the principal to contain the id as well, don't know how to do this and having problem finding good information on the topic. Add a model attribute to all my controllers that contain the whole user but this would be really ugly, like this. Account account = entityManager.find(Account.class, email); model.addAttribute("account", account); There are more way's as well and I have no clue which one is to prefer. I hope it's clear enough and thank you for any help on this. ====== Edit according to answer ======= I edited Account to implement UserDetails, it now looks like this (will fix the auto generated stuff later): @Entity @Table(name="Account") public class Account implements UserDetails { @Id private int id; private String username; private String password; private String firstName; private String lastName; @ManyToOne private University university; public Account() { } public Account(String username, String password, String firstName, String lastName, University university) { this.username = username; this.password = password; this.firstName = firstName; this.lastName = lastName; this.university = university; } public String getUsername() { return username; } public String getPassword() { return password; } public String getFirstName() { return firstName; } public String getLastName() { return lastName; } public void setUsername(String username) { this.username = username; } public void setPassword(String password) { this.password = password; } public void setFirstName(String firstName) { this.firstName = firstName; } public void setLastName(String lastName) { this.lastName = lastName; } public University getUniversity() { return university; } public void setUniversity(University university) { this.university = university; } public int getId() { return id; } public void setId(int id) { this.id = id; } @Override public Collection<? extends GrantedAuthority> getAuthorities() { // TODO Auto-generated method stub return null; } @Override public boolean isAccountNonExpired() { // TODO Auto-generated method stub return false; } @Override public boolean isAccountNonLocked() { // TODO Auto-generated method stub return false; } @Override public boolean isCredentialsNonExpired() { // TODO Auto-generated method stub return false; } @Override public boolean isEnabled() { // TODO Auto-generated method stub return true; } } I also added <%@ taglib prefix="sec" uri="http://www.springframework.org/security/tags" %> To my jsp files and trying to reach the id by <sec:authentication property="principal.id" /> This gives me the following org.springframework.beans.NotReadablePropertyException: Invalid property 'principal.id' of bean class [org.springframework.security.authentication.UsernamePasswordAuthenticationToken]: Bean property 'principal.id' is not readable or has an invalid getter method: Does the return type of the getter match the parameter type of the setter? ====== Edit 2 according to answer ======= I based my application on spring social samples and I never had to change anything until now. This are the files I think are relevant, please tell me if theres something you need to see besides this. AccountRepository.java public interface AccountRepository { void createAccount(Account account) throws UsernameAlreadyInUseException; Account findAccountByUsername(String username); } JdbcAccountRepository.java @Repository public class JdbcAccountRepository implements AccountRepository { private final JdbcTemplate jdbcTemplate; private final PasswordEncoder passwordEncoder; @Inject public JdbcAccountRepository(JdbcTemplate jdbcTemplate, PasswordEncoder passwordEncoder) { this.jdbcTemplate = jdbcTemplate; this.passwordEncoder = passwordEncoder; } @Transactional public void createAccount(Account user) throws UsernameAlreadyInUseException { try { jdbcTemplate.update( "insert into Account (firstName, lastName, username, university, password) values (?, ?, ?, ?, ?)", user.getFirstName(), user.getLastName(), user.getUsername(), user.getUniversity(), passwordEncoder.encode(user.getPassword())); } catch (DuplicateKeyException e) { throw new UsernameAlreadyInUseException(user.getUsername()); } } public Account findAccountByUsername(String username) { return jdbcTemplate.queryForObject("select username, firstName, lastName, university from Account where username = ?", new RowMapper<Account>() { public Account mapRow(ResultSet rs, int rowNum) throws SQLException { return new Account(rs.getString("username"), null, rs.getString("firstName"), rs.getString("lastName"), new University("test")); } }, username); } } security.xml <?xml version="1.0" encoding="UTF-8"?> <beans:beans xmlns="http://www.springframework.org/schema/security" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:beans="http://www.springframework.org/schema/beans" xsi:schemaLocation="http://www.springframework.org/schema/security http://www.springframework.org/schema/security/spring-security-3.1.xsd http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd"> <http pattern="/resources/**" security="none" /> <http pattern="/project/" security="none" /> <http use-expressions="true"> <!-- Authentication policy --> <form-login login-page="/signin" login-processing-url="/signin/authenticate" authentication-failure-url="/signin?error=bad_credentials" /> <logout logout-url="/signout" delete-cookies="JSESSIONID" /> <intercept-url pattern="/addcourse" access="isAuthenticated()" /> <intercept-url pattern="/courses/**/**/edit" access="isAuthenticated()" /> <intercept-url pattern="/users/**/edit" access="isAuthenticated()" /> </http> <authentication-manager alias="authenticationManager"> <authentication-provider> <password-encoder ref="passwordEncoder" /> <jdbc-user-service data-source-ref="dataSource" users-by-username-query="select username, password, true from Account where username = ?" authorities-by-username-query="select username, 'ROLE_USER' from Account where username = ?"/> </authentication-provider> <authentication-provider> <user-service> <user name="admin" password="admin" authorities="ROLE_USER, ROLE_ADMIN" /> </user-service> </authentication-provider> </authentication-manager> </beans:beans> And this is my try of implementing a UserDetailsService public class RepositoryUserDetailsService implements UserDetailsService { private final AccountRepository accountRepository; @Autowired public RepositoryUserDetailsService(AccountRepository repository) { this.accountRepository = repository; } @Override public UserDetails loadUserByUsername(String username) throws UsernameNotFoundException { Account user = accountRepository.findAccountByUsername(username); if (user == null) { throw new UsernameNotFoundException("No user found with username: " + username); } return user; } } Still gives me the same error, do I need to add the UserDetailsService somewhere? This is starting to be something else compared to my initial question, I should maybe start another question. Sorry for my lack of experience in this. I have to read up.

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  • Linq to LLBLGen query problem

    - by Jeroen Breuer
    Hello, I've got a Stored Procedure and i'm trying to convert it to a Linq to LLBLGen query. The query in Linq to LLBGen works, but when I trace the query which is send to sql server it is far from perfect. This is the Stored Procedure: ALTER PROCEDURE [dbo].[spDIGI_GetAllUmbracoProducts] -- Add the parameters for the stored procedure. @searchText nvarchar(255), @startRowIndex int, @maximumRows int, @sortExpression nvarchar(255) AS BEGIN SET @startRowIndex = @startRowIndex + 1 SET @searchText = '%' + @searchText + '%' -- SET NOCOUNT ON added to prevent extra result sets from -- interfering with SELECT statements. SET NOCOUNT ON; -- This is the query which will fetch all the UmbracoProducts. -- This query also supports paging and sorting. WITH UmbracoOverview As ( SELECT ROW_NUMBER() OVER( ORDER BY CASE WHEN @sortExpression = 'productName' THEN umbracoProduct.productName WHEN @sortExpression = 'productCode' THEN umbracoProduct.productCode END ASC, CASE WHEN @sortExpression = 'productName DESC' THEN umbracoProduct.productName WHEN @sortExpression = 'productCode DESC' THEN umbracoProduct.productCode END DESC ) AS row_num, umbracoProduct.umbracoProductId, umbracoProduct.productName, umbracoProduct.productCode FROM umbracoProduct INNER JOIN product ON umbracoProduct.umbracoProductId = product.umbracoProductId WHERE (umbracoProduct.productName LIKE @searchText OR umbracoProduct.productCode LIKE @searchText OR product.code LIKE @searchText OR product.description LIKE @searchText OR product.descriptionLong LIKE @searchText OR product.unitCode LIKE @searchText) ) SELECT UmbracoOverview.UmbracoProductId, UmbracoOverview.productName, UmbracoOverview.productCode FROM UmbracoOverview WHERE (row_num >= @startRowIndex AND row_num < (@startRowIndex + @maximumRows)) -- This query will count all the UmbracoProducts. -- This query is used for paging inside ASP.NET. SELECT COUNT (umbracoProduct.umbracoProductId) AS CountNumber FROM umbracoProduct INNER JOIN product ON umbracoProduct.umbracoProductId = product.umbracoProductId WHERE (umbracoProduct.productName LIKE @searchText OR umbracoProduct.productCode LIKE @searchText OR product.code LIKE @searchText OR product.description LIKE @searchText OR product.descriptionLong LIKE @searchText OR product.unitCode LIKE @searchText) END This is my Linq to LLBLGen query: using System.Linq.Dynamic; var q = ( from up in MetaData.UmbracoProduct join p in MetaData.Product on up.UmbracoProductId equals p.UmbracoProductId where up.ProductCode.Contains(searchText) || up.ProductName.Contains(searchText) || p.Code.Contains(searchText) || p.Description.Contains(searchText) || p.DescriptionLong.Contains(searchText) || p.UnitCode.Contains(searchText) select new UmbracoProductOverview { UmbracoProductId = up.UmbracoProductId, ProductName = up.ProductName, ProductCode = up.ProductCode } ).OrderBy(sortExpression); //Save the count in HttpContext.Current.Items. This value will only be saved during 1 single HTTP request. HttpContext.Current.Items["AllProductsCount"] = q.Count(); //Returns the results paged. return q.Skip(startRowIndex).Take(maximumRows).ToList<UmbracoProductOverview>(); This is my Initial expression to process: value(SD.LLBLGen.Pro.LinqSupportClasses.DataSource`1[Eurofysica.DB.EntityClasses.UmbracoProductEntity]).Join(value(SD.LLBLGen.Pro.LinqSupportClasses.DataSource`1[Eurofysica.DB.EntityClasses.ProductEntity]), up => up.UmbracoProductId, p => p.UmbracoProductId, (up, p) => new <>f__AnonymousType0`2(up = up, p = p)).Where(<>h__TransparentIdentifier0 => (((((<>h__TransparentIdentifier0.up.ProductCode.Contains(value(Eurofysica.BusinessLogic.BLL.Controllers.UmbracoProductController+<>c__DisplayClass1).searchText) || <>h__TransparentIdentifier0.up.ProductName.Contains(value(Eurofysica.BusinessLogic.BLL.Controllers.UmbracoProductController+<>c__DisplayClass1).searchText)) || <>h__TransparentIdentifier0.p.Code.Contains(value(Eurofysica.BusinessLogic.BLL.Controllers.UmbracoProductController+<>c__DisplayClass1).searchText)) || <>h__TransparentIdentifier0.p.Description.Contains(value(Eurofysica.BusinessLogic.BLL.Controllers.UmbracoProductController+<>c__DisplayClass1).searchText)) || <>h__TransparentIdentifier0.p.DescriptionLong.Contains(value(Eurofysica.BusinessLogic.BLL.Controllers.UmbracoProductController+<>c__DisplayClass1).searchText)) || <>h__TransparentIdentifier0.p.UnitCode.Contains(value(Eurofysica.BusinessLogic.BLL.Controllers.UmbracoProductController+<>c__DisplayClass1).searchText))).Select(<>h__TransparentIdentifier0 => new UmbracoProductOverview() {UmbracoProductId = <>h__TransparentIdentifier0.up.UmbracoProductId, ProductName = <>h__TransparentIdentifier0.up.ProductName, ProductCode = <>h__TransparentIdentifier0.up.ProductCode}).OrderBy( => .ProductName).Count() Now this is how the queries look like that are send to sql server: Select query: Query: SELECT [LPA_L2].[umbracoProductId] AS [UmbracoProductId], [LPA_L2].[productName] AS [ProductName], [LPA_L2].[productCode] AS [ProductCode] FROM ( [eurofysica].[dbo].[umbracoProduct] [LPA_L2] INNER JOIN [eurofysica].[dbo].[product] [LPA_L3] ON [LPA_L2].[umbracoProductId] = [LPA_L3].[umbracoProductId]) WHERE ( ( ( ( ( ( ( ( [LPA_L2].[productCode] LIKE @ProductCode1) OR ( [LPA_L2].[productName] LIKE @ProductName2)) OR ( [LPA_L3].[code] LIKE @Code3)) OR ( [LPA_L3].[description] LIKE @Description4)) OR ( [LPA_L3].[descriptionLong] LIKE @DescriptionLong5)) OR ( [LPA_L3].[unitCode] LIKE @UnitCode6)))) Parameter: @ProductCode1 : String. Length: 2. Precision: 0. Scale: 0. Direction: Input. Value: "%%". Parameter: @ProductName2 : String. Length: 2. Precision: 0. Scale: 0. Direction: Input. Value: "%%". Parameter: @Code3 : String. Length: 2. Precision: 0. Scale: 0. Direction: Input. Value: "%%". Parameter: @Description4 : String. Length: 2. Precision: 0. Scale: 0. Direction: Input. Value: "%%". Parameter: @DescriptionLong5 : String. Length: 2. Precision: 0. Scale: 0. Direction: Input. Value: "%%". Parameter: @UnitCode6 : String. Length: 2. Precision: 0. Scale: 0. Direction: Input. Value: "%%". Count query: Query: SELECT TOP 1 COUNT(*) AS [LPAV_] FROM (SELECT [LPA_L2].[umbracoProductId] AS [UmbracoProductId], [LPA_L2].[productName] AS [ProductName], [LPA_L2].[productCode] AS [ProductCode] FROM ( [eurofysica].[dbo].[umbracoProduct] [LPA_L2] INNER JOIN [eurofysica].[dbo].[product] [LPA_L3] ON [LPA_L2].[umbracoProductId] = [LPA_L3].[umbracoProductId]) WHERE ( ( ( ( ( ( ( ( [LPA_L2].[productCode] LIKE @ProductCode1) OR ( [LPA_L2].[productName] LIKE @ProductName2)) OR ( [LPA_L3].[code] LIKE @Code3)) OR ( [LPA_L3].[description] LIKE @Description4)) OR ( [LPA_L3].[descriptionLong] LIKE @DescriptionLong5)) OR ( [LPA_L3].[unitCode] LIKE @UnitCode6))))) [LPA_L1] Parameter: @ProductCode1 : String. Length: 2. Precision: 0. Scale: 0. Direction: Input. Value: "%%". Parameter: @ProductName2 : String. Length: 2. Precision: 0. Scale: 0. Direction: Input. Value: "%%". Parameter: @Code3 : String. Length: 2. Precision: 0. Scale: 0. Direction: Input. Value: "%%". Parameter: @Description4 : String. Length: 2. Precision: 0. Scale: 0. Direction: Input. Value: "%%". Parameter: @DescriptionLong5 : String. Length: 2. Precision: 0. Scale: 0. Direction: Input. Value: "%%". Parameter: @UnitCode6 : String. Length: 2. Precision: 0. Scale: 0. Direction: Input. Value: "%%". As you can see no sorting or paging is done (like in my Stored Procedure). This is probably done inside the code after all the results are fetched. This costs a lot of performance! Does anybody know how I can convert my Stored Procedure to Linq to LLBLGen the proper way?

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  • CoreData update problems

    - by kpower
    My app makes updates in background thread then saves context changes. And in main context there is a table view that works with NSFetchedResultsController. For some time updates work correctly, but then exception is thrown. To check this I've added NSLog(@"%@", [self.controller fetchedObjects]); to -controllerDidChangeContent:. Here is what I got: "<PRBattle: 0x6d30530> (entity: PRBattle; id: 0x6d319d0 <x-coredata://882BD521-90CD-4682-B19A-000A4976E471/PRBattle/p2> ; data: {\n battleId = \"-1\";\n finishedAt = \"2012-11-06 11:37:36 +0000\";\n opponent = \"0x6d2f730 <x-coredata://882BD521-90CD-4682-B19A-000A4976E471/PROpponent/p1>\";\n opponentScore = nil;\n score = nil;\n status = 4;\n})", "<PRBattle: 0x6d306f0> (entity: PRBattle; id: 0x6d319f0 <x-coredata://882BD521-90CD-4682-B19A-000A4976E471/PRBattle/p1> ; data: {\n battleId = \"-1\";\n finishedAt = \"2012-11-06 11:37:36 +0000\";\n opponent = \"0x6d2ddb0 <x-coredata://882BD521-90CD-4682-B19A-000A4976E471/PROpponent/p3>\";\n opponentScore = nil;\n score = nil;\n status = 4;\n})", "<PRBattle: 0x6d30830> (entity: PRBattle; id: 0x6d31650 <x-coredata://882BD521-90CD-4682-B19A-000A4976E471/PRBattle/p11> ; data: <fault>)", "<PRBattle: 0x6d306b0> (entity: PRBattle; id: 0x6d319e0 <x-coredata://882BD521-90CD-4682-B19A-000A4976E471/PRBattle/p5> ; data: {\n battleId = 325;\n finishedAt = nil;\n opponent = \"0x6d2f730 <x-coredata://882BD521-90CD-4682-B19A-000A4976E471/PROpponent/p1>\";\n opponentScore = 91;\n score = 59;\n status = 3;\n})", "<PRBattle: 0x6d30730> (entity: PRBattle; id: 0x6d31a00 <x-coredata://882BD521-90CD-4682-B19A-000A4976E471/PRBattle/p6> ; data: {\n battleId = 323;\n finishedAt = nil;\n opponent = \"0x6d2ddb0 <x-coredata://882BD521-90CD-4682-B19A-000A4976E471/PROpponent/p3>\";\n opponentScore = 0;\n score = 0;\n status = 3;\n})", "<PRBattle: 0x6d307b0> (entity: PRBattle; id: 0x6d31630 <x-coredata://882BD521-90CD-4682-B19A-000A4976E471/PRBattle/p9> ; data: {\n battleId = 370;\n finishedAt = \"2012-11-06 14:24:14 +0000\";\n opponent = \"0x79a8e90 <x-coredata://882BD521-90CD-4682-B19A-000A4976E471/PROpponent/p2>\";\n opponentScore = 180;\n score = 180;\n status = 4;\n})", "<PRBattle: 0x6d307f0> (entity: PRBattle; id: 0x6d31640 <x-coredata://882BD521-90CD-4682-B19A-000A4976E471/PRBattle/p10> ; data: {\n battleId = 309;\n finishedAt = \"2012-11-02 01:19:27 +0000\";\n opponent = \"0x79a8e90 <x-coredata://882BD521-90CD-4682-B19A-000A4976E471/PROpponent/p2>\";\n opponentScore = 120;\n score = 240;\n status = 4;\n})", "<PRBattle: 0x6d30770> (entity: PRBattle; id: 0x6d31620 <x-coredata://882BD521-90CD-4682-B19A-000A4976E471/PRBattle/p7> ; data: {\n battleId = 315;\n finishedAt = \"2012-11-02 02:26:24 +0000\";\n opponent = \"0x79a8e90 <x-coredata://882BD521-90CD-4682-B19A-000A4976E471/PROpponent/p2>\";\n opponentScore = 119;\n score = 179;\n status = 4;\n})" ) Faulted object (0xe972610) here causes crash. I've logged data during update & before saving. This object is in updatedObjects only. Why can this method return "bad" object? (Moreover, during updates this object is affected almost each update. And only after some passes becomes "bad" one). P.S.: I use RestKit to manage CoreData. UPDATED: The exception was got, when I did smth. like this: for (PRBattle *battle in [self.controller fetchedObjects) { switch (battle.statusScalar) { case ... default: [battle willAccessValueForKey:nil]; NSAssert1(NO, @"Unexpected battle status found: %@", battle); } } The exception is on line with -willAccessValueForKey:. Scalar status for battle is enum, that is bind to integer values 1..4. I've mentioned all possible values in switch's cases (above default:). And the last one has break;. So this one is possible only when battle.statusScalar returns non-enum value. Status scalar implementation in PRBattle: - (PRBattleStatuses)statusScalar { [self willAccessValueForKey:@"statusScalar"]; PRBattleStatuses result = (PRBattleStatuses)[self.status integerValue]; [self didAccessValueForKey:@"statusScalar"]; return result; } And battle.status has validation rules: - min-value: 1 - max-value: 4 - default: no value And the last thing - debug log: objc[4664]: EXCEPTIONS: throwing 0x7d33f80 (object 0xe67d2a0, a _NSCoreDataException) objc[4664]: EXCEPTIONS: searching through frame [ip=0x97b401 sp=0xbfffd9b0] for exception 0x7d33f60 objc[4664]: EXCEPTIONS: catch(id) objc[4664]: EXCEPTIONS: unwinding through frame [ip=0x97b401 sp=0xbfffd9b0] for exception 0x7d33f60 objc[4664]: EXCEPTIONS: handling exception 0x7d33f60 at 0x97b79f objc[4664]: EXCEPTIONS: rethrowing current exception objc[4664]: EXCEPTIONS: searching through frame [ip=0x97b911 sp=0xbfffd9b0] for exception 0x7d33f60 objc[4664]: EXCEPTIONS: searching through frame [ip=0x9ac8b7 sp=0xbfffdc20] for exception 0x7d33f60 objc[4664]: EXCEPTIONS: searching through frame [ip=0x97ee80 sp=0xbfffdc40] for exception 0x7d33f60 objc[4664]: EXCEPTIONS: searching through frame [ip=0x361d0 sp=0xbfffdc70] for exception 0x7d33f60 objc[4664]: EXCEPTIONS: searching through frame [ip=0xa701d8 sp=0xbfffde10] for exception 0x7d33f60 objc[4664]: EXCEPTIONS: catch(id) objc[4664]: EXCEPTIONS: unwinding through frame [ip=0x97b911 sp=0xbfffd9b0] for exception 0x7d33f60 objc[4664]: EXCEPTIONS: finishing handler objc[4664]: EXCEPTIONS: searching through frame [ip=0x97b963 sp=0xbfffd9b0] for exception 0x7d33f60 objc[4664]: EXCEPTIONS: searching through frame [ip=0x9ac8b7 sp=0xbfffdc20] for exception 0x7d33f60 objc[4664]: EXCEPTIONS: searching through frame [ip=0x97ee80 sp=0xbfffdc40] for exception 0x7d33f60 objc[4664]: EXCEPTIONS: searching through frame [ip=0x361d0 sp=0xbfffdc70] for exception 0x7d33f60 objc[4664]: EXCEPTIONS: searching through frame [ip=0xa701d8 sp=0xbfffde10] for exception 0x7d33f60 objc[4664]: EXCEPTIONS: catch(id) objc[4664]: EXCEPTIONS: unwinding through frame [ip=0x97b963 sp=0xbfffd9b0] for exception 0x7d33f60 objc[4664]: EXCEPTIONS: unwinding through frame [ip=0x9ac8b7 sp=0xbfffdc20] for exception 0x7d33f60 objc[4664]: EXCEPTIONS: unwinding through frame [ip=0x97ee80 sp=0xbfffdc40] for exception 0x7d33f60 objc[4664]: EXCEPTIONS: unwinding through frame [ip=0x361d0 sp=0xbfffdc70] for exception 0x7d33f60 objc[4664]: EXCEPTIONS: unwinding through frame [ip=0x3656f sp=0xbfffdc70] for exception 0x7d33f60 objc[4664]: EXCEPTIONS: unwinding through frame [ip=0xa701d8 sp=0xbfffde10] for exception 0x7d33f60 objc[4664]: EXCEPTIONS: handling exception 0x7d33f60 at 0xa701f5 2012-11-07 13:37:55.463 TestApp[4664:fb03] CoreData: error: Serious application error. An exception was caught from the delegate of NSFetchedResultsController during a call to -controllerDidChangeContent:. CoreData could not fulfill a fault for '0x6d31650 <x-coredata://882BD521-90CD-4682-B19A-000A4976E471/PRBattle/p10>' with userInfo { NSAffectedObjectsErrorKey = ( "<PRBattle: 0x6d30830> (entity: PRBattle; id: 0x6d31650 <x-coredata://882BD521-90CD-4682-B19A-000A4976E471/PRBattle/p10> ; data: <fault>)" ); }

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  • XSLT big integer (int64) handling msxml

    - by Farid Z
    When trying to do math on an big integer (int64) large number in xslt template I get the wrong result since there is no native 64-bit integer support in xslt (xslt number is 64-bit double). I am using msxml 6.0 on Windows XP SP3. Are there any work around for this on Windows? <tables> <table> <table_schem>REPADMIN</table_schem> <table_name>TEST_DESCEND_IDENTITY_BIGINT</table_name> <column> <col_name>COL1</col_name> <identity> <col_min_val>9223372036854775805</col_min_val> <col_max_val>9223372036854775805</col_max_val> <autoincrementvalue>9223372036854775807</autoincrementvalue> <autoincrementstart>9223372036854775807</autoincrementstart> <autoincrementinc>-1</autoincrementinc> </identity> </column> </table> </tables> This test returns true due to overflow (I am assuming) but actually is false if I could tell the xslt processor somehow to use int64 rather than the default 64-bit double for the data since big integer is the actual data type for the numbers in the xml input. <xsl:when test="autoincrementvalue = (col_min_val + autoincrementinc)"> <xsl:value-of select="''"/> </xsl:when> here is the complete template <xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform" > <!--Reseed Derby identity column--> <xsl:output omit-xml-declaration='yes' method='text' /> <xsl:param name="stmtsep">;</xsl:param> <xsl:param name="schemprefix"></xsl:param> <xsl:template match="tables"> <xsl:variable name="identitycount" select="count(table/column/identity)"></xsl:variable> <xsl:for-each select="table/column/identity"> <xsl:variable name="table_schem" select="../../table_schem"></xsl:variable> <xsl:variable name="table_name" select="../../table_name"></xsl:variable> <xsl:variable name="tablespec"> <xsl:if test="$schemprefix"> <xsl:value-of select="$table_schem"/>.</xsl:if><xsl:value-of select="$table_name"/></xsl:variable> <xsl:variable name="col_name" select="../col_name"></xsl:variable> <xsl:variable name="newstart"> <xsl:choose> <xsl:when test="autoincrementinc > 0"> <xsl:choose> <xsl:when test="col_max_val = '' and autoincrementvalue = autoincrementstart"> <xsl:value-of select="''"/> </xsl:when> <xsl:when test="col_max_val = ''"> <xsl:value-of select="autoincrementstart"/> </xsl:when> <xsl:when test="autoincrementvalue = (col_max_val + autoincrementinc)"> <xsl:value-of select="''"/> </xsl:when> <xsl:when test="(col_max_val + autoincrementinc) &lt; autoincrementstart"> <xsl:value-of select="autoincrementstart"/> </xsl:when> <xsl:otherwise> <xsl:value-of select="col_max_val + autoincrementinc"/> </xsl:otherwise> </xsl:choose> </xsl:when> <xsl:when test="autoincrementinc &lt; 0"> <xsl:choose> <xsl:when test="col_min_val = '' and autoincrementvalue = autoincrementstart"> <xsl:value-of select="''"/> </xsl:when> <xsl:when test="col_min_val = ''"> <xsl:value-of select="autoincrementstart"/> </xsl:when> <xsl:when test="autoincrementvalue = (col_min_val + autoincrementinc)"> <xsl:value-of select="''"/> </xsl:when> <xsl:when test="(col_min_val + autoincrementinc) > autoincrementstart"> <xsl:value-of select="autoincrementstart"/> </xsl:when> <xsl:otherwise> <xsl:value-of select="col_min_val + autoincrementinc"/> </xsl:otherwise> </xsl:choose> </xsl:when> </xsl:choose> </xsl:variable> <xsl:if test="not(position()=1)"><xsl:text> </xsl:text></xsl:if> <xsl:choose> <!--restart with ddl changes both the next identity value AUTOINCREMENTVALUE and the identity start number AUTOINCREMENTSTART eventhough in this casewe only want to change only the next identity number--> <xsl:when test="$newstart != '' and $newstart != autoincrementvalue">alter table <xsl:value-of select="$tablespec"/> alter column <xsl:value-of select="$col_name"/> restart with <xsl:value-of select="$newstart"/><xsl:if test="$identitycount>1">;</xsl:if></xsl:when> <xsl:otherwise>-- reseed <xsl:value-of select="$tablespec"/> is not necessary</xsl:otherwise> </xsl:choose> </xsl:for-each> </xsl:template> </xsl:stylesheet>

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  • program not working as expected!

    - by wilson88
    Can anyone just help spot why my program is not returning the expected output.related to my previous question.Am passing a vector by refrence, I want to see whats in the container before I copy them to another loaction.if u remove comments on loadRage, u will see bids are generated by the trader. #include <iostream> #include <vector> #include <string> #include <algorithm> #include <cstdlib> #include <iomanip> using namespace std; const int NUMSELLER = 1; const int NUMBUYER = 1; const int NUMBIDS = 20; const int MINQUANTITY = 1; const int MAXQUANTITY = 30; const int MINPRICE =100; const int MAXPRICE = 150; int s=0; int trdId; // Bid, simple container for values struct Bid { int bidId, trdId, qty, price; char type; // for sort and find. bool operator<(const Bid &other) const { return price < other.price; } bool operator==(int bidId) const { return this->bidId == bidId; } }; // alias to the list, make type consistent typedef vector<Bid> BidList; // this class generates bids! class Trader { private: int nextBidId; public: Trader(); Bid getNextBid(); Bid getNextBid(char type); // generate a number of bids void loadRange(BidList &, int size); void loadRange(BidList &, char type, int size); void setVector(); }; Trader::Trader() : nextBidId(1) {} #define RAND_RANGE(min, max) ((rand() % (max-min+1)) + min) Bid Trader::getNextBid() { char type = RAND_RANGE('A','B'); return getNextBid(type); } Bid Trader::getNextBid(char type) { for(int i = 0; i < NUMSELLER+NUMBUYER; i++) { // int trdId = RAND_RANGE(1,9); if (s<10){trdId=0;type='A';} else {trdId=1;type='B';} s++; int qty = RAND_RANGE(MINQUANTITY, MAXQUANTITY); int price = RAND_RANGE(MINPRICE, MAXPRICE); Bid bid = {nextBidId++, trdId, qty, price, type}; return bid; } } //void Trader::loadRange(BidList &list, int size) { // for (int i=0; i<size; i++) { list.push_back(getNextBid()); } //} // //void Trader::loadRange(BidList &list, char type, int size) { // for (int i=0; i<size; i++) { list.push_back(getNextBid(type)); } //} //---------------------------AUCTIONEER------------------------------------------- class Auctioneer { vector<Auctioneer> List; Trader trader; vector<Bid> list; public: Auctioneer(){}; void accept_bids(const BidList& bid); }; typedef vector<Auctioneer*> bidlist; void Auctioneer::accept_bids(const BidList& bid){ BidList list; //copy (BidList.begin(),BidList.end(),list); } //all the happy display commands void show(const Bid &bid) { cout << "\tBid\t(" << setw(3) << bid.bidId << "\t " << setw(3) << bid.trdId << "\t " << setw(3) << bid.type <<"\t " << setw(3) << bid.qty <<"\t " << setw(3) << bid.price <<")\t\n " ; } void show(const BidList &list) { cout << "\t\tBidID | TradID | Type | Qty | Price \n\n"; for(BidList::const_iterator itr=list.begin(); itr != list.end(); ++itr) { //cout <<"\t\t"; show(*itr); cout << endl; } cout << endl; } //search now checks for failure void show(const char *msg, const BidList &list) { cout << msg << endl; show(list); } void searchTest(BidList &list, int bidId) { cout << "Searching for Bid " << bidId << endl; BidList::const_iterator itr = find(list.begin(), list.end(), bidId); if (itr==list.end()) { cout << "Bid not found."; } else { cout << "Bid has been found. Its : "; show(*itr); } cout << endl; } //comparator function for price: returns true when x belongs before y bool compareBidList(Bid one, Bid two) { if (one.type == 'A' && two.type == 'B') return (one.price < two.price); return false; } void sort(BidList &bidlist) { sort(bidlist.begin(), bidlist.end(), compareBidList); } int main(int argc, char **argv) { Trader trader; BidList bidlist; Auctioneer auctioneer; //bidlist list; auctioneer.accept_bids(bidlist); //trader.loadRange(bidlist, NUMBIDS); show("Bids before sort:", bidlist); sort(bidlist); show("Bids after sort:", bidlist); system("pause"); return 0; }

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  • Need guidance on a Google Map application that has to show 250 000 polylines.

    - by lucian.jp
    I am looking for advice for an application I am developing that uses Google Map. Summary: A user has a list of criteria for searching a street segment that fulfills the criteria. The street segments will be colored with 3 colors for showing those below average, average and over average. Then the user clicks on the street segment to see an information window showing the properties of that specific segment hiding those not selected until he/she closes the window and other polyline becomes visible again. This looks quite like the Monopoly City Streets game Hasbro made some month ago the difference being I do not use Flash, I can’t use Open Street Map because it doesn’t list street segment (if it does the IDs won’t be the same anyway) and I do not have to show Google sketch building over. Information: I have a database of street segments with IDs, polyline points and centroid. The database has 6,000,000 street segment records in it. To narrow the generated data a bit we focus on city. The largest city we must show has 250,000 street segments. This means 250,000 line segment polyline to show. Our longest polyline uses 9600 characters which is stored in two 8000 varchar columns in SQL Server 2008. We need to use the API v3 because it is faster than the API v2 and the application will be ported to iPhone. For now it's an ASP.NET 3.5 with SQl Server 2008 application. Performance is a priority. Problems: Most of the demo projects that do this are made with API v2. So besides tutorial on the Google API v3 reference page I have nothing to compare performance or technology use to achieve my goal. There is no available .NET wrapper for the API v3 yet. Generating a 250,000 line segment polyline creates a heavy file which takes time to transfer and parse. (I have found a demo of one polyline of 390,000 points. I think the encoder would be far less efficient with more polylines with less points since there will be less rounding.) Since streets segments are shown based on criteria, polylines must be dynamically created and cache can't be used. Some thoughts: KML/KMZ: Pros: Since it is a standard we can easily load Bing maps, Yahoo! maps, Google maps, Google Earth, with the same KML file. The data generation would be the same. Cons: LineString in KML cannot be encoded polyline like the Google map API can handle. So it would probably be bigger and slower to display. Zipping the file at the size it will take more processing time and require the client side to uncompress the data and I am not quite sure with 250,000 data how an iPhone would handle this and how a server would handle 40 users browsing at the same time. JavaScript file: Pros: JavaScript file can have encoded polyline and would significantly reduce the file to transfer. Cons: Have to create my own stripped version of API v3 to add overlays, create polyline, etc. It is more complex than just create a KML file and point to the source. GeoRSS: This option isn't adapted for my needs I think, but I could be wrong. MapServer: I saw some post suggesting using MapServer to generate overlays. Not quite sure for the connection with our database and the performance it would give. Plus it requires a plugin for generating KML. It seems to me that it wouldn't allow me to do better than creating my own KML or JavaScript file. Maintenance would be simpler without. Monopoly City Streets: The game is now over, but for those who know what I am talking about Monopoly City Streets was showing at max zoom level only the streets that the centroid was inside the Bounds of the window. Moving the map was sending request to the server for the new streets to show. While I think this was ingenious, I have no idea how to implement something similar. The only thing I thought about was to compare if the long was inside the bound of map area X and same with Y. While this could improve performance significantly at high zoom level, this would give nothing when showing a whole city. Clustering: While cluster is awesome for marker, it seems we cannot cluster polylines. I would have liked something like MarkerClusterer for polylines and be able to cluster by my 3 polyline colors. This will probably stay as a “would have been freaking awesome but forget it”. Arrow: I will have in a future version to show a direction for the polyline and will have to show an arrow at the centroid. Loading an image or marker will only double my data so creating a custom overlay will probably be my only option. I have found that demo for something similar I would like to achieve. Unfortunately, the demo is very slow, but I only wish to show 1 arrow per polyline and not multiple like the demo. This functionality will depend on the format of data since I don't think KML support custom overlays. Criteria: While the application is done with ASP.NET 3.5, the port to the iPhone won't use the web to show the application and be limited in screen size for selecting the criteria. This is why I was more orienting on a service or page generating the file based on criteria passed in parameters. The service would than generate the file I need to display the polylines on the map. I could also create an aspx page that does this. The aspx page is more documented than the service way. There should be a reason. Questions: Should I create a web service to returns the street segments file or create an aspx page that return the file? Should I create a JavaScript file with encoded polyline or a KML with longitude/latitude based on the fact that maximum longitude/latitude polyline have 9600 characters and I have to render maximum 250,000 line segment polyline. Or should I go with a MapServer that generate the overlay? Will I be able to display simple arrow on the polyline on the next version. In case of KML generation is it faster to create the file with XDocument, XmlDocument, XmlWriter and this manually or just serialize the street segment in the stream? This is more a brainstorming Stack Overflow question than an actual code problem. Any answer helping narrow the possibilities is as good as someone having all the knowledge to point me out a better choice.

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  • Building applications with WCF - Intro

    - by skjagini
    I am going to write series of articles using Windows Communication Framework (WCF) to develop client and server applications and this is the first part of that series. What is WCF As Juwal puts in his Programming WCF book, WCF provides an SDK for developing and deploying services on Windows, provides runtime environment to expose CLR types as services and consume services as CLR types. Building services with WCF is incredibly easy and it’s implementation provides a set of industry standards and off the shelf plumbing including service hosting, instance management, reliability, transaction management, security etc such that it greatly increases productivity Scenario: Lets consider a typical bank customer trying to create an account, deposit amount and transfer funds between accounts, i.e. checking and savings. To make it interesting, we are going to divide the functionality into multiple services and each of them working with database directly. We will run test cases with and without transactional support across services. In this post we will build contracts, services, data access layer, unit tests to verify end to end communication etc, nothing big stuff here and we dig into other features of the WCF in subsequent posts with incremental changes. In any distributed architecture we have two pieces i.e. services and clients. Services as the name implies provide functionality to execute various pieces of business logic on the server, and clients providing interaction to the end user. Services can be built with Web Services or with WCF. Service built on WCF have the advantage of binding independent, i.e. can run against TCP and HTTP protocol without any significant changes to the code. Solution Services Profile: For creating a new bank customer, getting details about existing customer ProfileContract ProfileService Checking Account: To get checking account balance, deposit or withdraw amount CheckingAccountContract CheckingAccountService Savings Account: To get savings account balance, deposit or withdraw amount SavingsAccountContract SavingsAccountService ServiceHost: To host services, i.e. running the services at particular address, binding and contract where client can connect to Client: Helps end user to use services like creating account and amount transfer between the accounts BankDAL: Data access layer to work with database     BankDAL It’s no brainer not to use an ORM as many matured products are available currently in market including Linq2Sql, Entity Framework (EF), LLblGenPro etc. For this exercise I am going to use Entity Framework 4.0, CTP 5 with code first approach. There are two approaches when working with data, data driven and code driven. In data driven we start by designing tables and their constrains in database and generate entities in code while in code driven (code first) approach entities are defined in code and the metadata generated from the entities is used by the EF to create tables and table constrains. In previous versions the entity classes had  to derive from EF specific base classes. In EF 4 it  is not required to derive from any EF classes, the entities are not only persistence ignorant but also enable full test driven development using mock frameworks.  Application consists of 3 entities, Customer entity which contains Customer details; CheckingAccount and SavingsAccount to hold the respective account balance. We could have introduced an Account base class for CheckingAccount and SavingsAccount which is certainly possible with EF mappings but to keep it simple we are just going to follow 1 –1 mapping between entity and table mappings. Lets start out by defining a class called Customer which will be mapped to Customer table, observe that the class is simply a plain old clr object (POCO) and has no reference to EF at all. using System;   namespace BankDAL.Model { public class Customer { public int Id { get; set; } public string FullName { get; set; } public string Address { get; set; } public DateTime DateOfBirth { get; set; } } }   In order to inform EF about the Customer entity we have to define a database context with properties of type DbSet<> for every POCO which needs to be mapped to a table in database. EF uses convention over configuration to generate the metadata resulting in much less configuration. using System.Data.Entity;   namespace BankDAL.Model { public class BankDbContext: DbContext { public DbSet<Customer> Customers { get; set; } } }   Entity constrains can be defined through attributes on Customer class or using fluent syntax (no need to muscle with xml files), CustomerConfiguration class. By defining constrains in a separate class we can maintain clean POCOs without corrupting entity classes with database specific information.   using System; using System.Data.Entity.ModelConfiguration;   namespace BankDAL.Model { public class CustomerConfiguration: EntityTypeConfiguration<Customer> { public CustomerConfiguration() { Initialize(); }   private void Initialize() { //Setting the Primary Key this.HasKey(e => e.Id);   //Setting required fields this.HasRequired(e => e.FullName); this.HasRequired(e => e.Address); //Todo: Can't create required constraint as DateOfBirth is not reference type, research it //this.HasRequired(e => e.DateOfBirth); } } }   Any queries executed against Customers property in BankDbContext are executed against Cusomers table. By convention EF looks for connection string with key of BankDbContext when working with the context.   We are going to define a helper class to work with Customer entity with methods for querying, adding new entity etc and these are known as repository classes, i.e., CustomerRepository   using System; using System.Data.Entity; using System.Linq; using BankDAL.Model;   namespace BankDAL.Repositories { public class CustomerRepository { private readonly IDbSet<Customer> _customers;   public CustomerRepository(BankDbContext bankDbContext) { if (bankDbContext == null) throw new ArgumentNullException(); _customers = bankDbContext.Customers; }   public IQueryable<Customer> Query() { return _customers; }   public void Add(Customer customer) { _customers.Add(customer); } } }   From the above code it is observable that the Query methods returns customers as IQueryable i.e. customers are retrieved only when actually used i.e. iterated. Returning as IQueryable also allows to execute filtering and joining statements from business logic using lamba expressions without cluttering the data access layer with tens of methods.   Our CheckingAccountRepository and SavingsAccountRepository look very similar to each other using System; using System.Data.Entity; using System.Linq; using BankDAL.Model;   namespace BankDAL.Repositories { public class CheckingAccountRepository { private readonly IDbSet<CheckingAccount> _checkingAccounts;   public CheckingAccountRepository(BankDbContext bankDbContext) { if (bankDbContext == null) throw new ArgumentNullException(); _checkingAccounts = bankDbContext.CheckingAccounts; }   public IQueryable<CheckingAccount> Query() { return _checkingAccounts; }   public void Add(CheckingAccount account) { _checkingAccounts.Add(account); }   public IQueryable<CheckingAccount> GetAccount(int customerId) { return (from act in _checkingAccounts where act.CustomerId == customerId select act); }   } } The repository classes look very similar to each other for Query and Add methods, with the help of C# generics and implementing repository pattern (Martin Fowler) we can reduce the repeated code. Jarod from ElegantCode has posted an article on how to use repository pattern with EF which we will implement in the subsequent articles along with WCF Unity life time managers by Drew Contracts It is very easy to follow contract first approach with WCF, define the interface and append ServiceContract, OperationContract attributes. IProfile contract exposes functionality for creating customer and getting customer details.   using System; using System.ServiceModel; using BankDAL.Model;   namespace ProfileContract { [ServiceContract] public interface IProfile { [OperationContract] Customer CreateCustomer(string customerName, string address, DateTime dateOfBirth);   [OperationContract] Customer GetCustomer(int id);   } }   ICheckingAccount contract exposes functionality for working with checking account, i.e., getting balance, deposit and withdraw of amount. ISavingsAccount contract looks the same as checking account.   using System.ServiceModel;   namespace CheckingAccountContract { [ServiceContract] public interface ICheckingAccount { [OperationContract] decimal? GetCheckingAccountBalance(int customerId);   [OperationContract] void DepositAmount(int customerId,decimal amount);   [OperationContract] void WithdrawAmount(int customerId, decimal amount);   } }   Services   Having covered the data access layer and contracts so far and here comes the core of the business logic, i.e. services.   .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } ProfileService implements the IProfile contract for creating customer and getting customer detail using CustomerRepository. using System; using System.Linq; using System.ServiceModel; using BankDAL; using BankDAL.Model; using BankDAL.Repositories; using ProfileContract;   namespace ProfileService { [ServiceBehavior(IncludeExceptionDetailInFaults = true)] public class Profile: IProfile { public Customer CreateAccount( string customerName, string address, DateTime dateOfBirth) { Customer cust = new Customer { FullName = customerName, Address = address, DateOfBirth = dateOfBirth };   using (var bankDbContext = new BankDbContext()) { new CustomerRepository(bankDbContext).Add(cust); bankDbContext.SaveChanges(); } return cust; }   public Customer CreateCustomer(string customerName, string address, DateTime dateOfBirth) { return CreateAccount(customerName, address, dateOfBirth); } public Customer GetCustomer(int id) { return new CustomerRepository(new BankDbContext()).Query() .Where(i => i.Id == id).FirstOrDefault(); }   } } From the above code you shall observe that we are calling bankDBContext’s SaveChanges method and there is no save method specific to customer entity because EF manages all the changes centralized at the context level and all the pending changes so far are submitted in a batch and it is represented as Unit of Work. Similarly Checking service implements ICheckingAccount contract using CheckingAccountRepository, notice that we are throwing overdraft exception if the balance falls by zero. WCF has it’s own way of raising exceptions using fault contracts which will be explained in the subsequent articles. SavingsAccountService is similar to CheckingAccountService. using System; using System.Linq; using System.ServiceModel; using BankDAL.Model; using BankDAL.Repositories; using CheckingAccountContract;   namespace CheckingAccountService { [ServiceBehavior(IncludeExceptionDetailInFaults = true)] public class Checking:ICheckingAccount { public decimal? GetCheckingAccountBalance(int customerId) { using (var bankDbContext = new BankDbContext()) { CheckingAccount account = (new CheckingAccountRepository(bankDbContext) .GetAccount(customerId)).FirstOrDefault();   if (account != null) return account.Balance;   return null; } }   public void DepositAmount(int customerId, decimal amount) { using(var bankDbContext = new BankDbContext()) { var checkingAccountRepository = new CheckingAccountRepository(bankDbContext); CheckingAccount account = (checkingAccountRepository.GetAccount(customerId)) .FirstOrDefault();   if (account == null) { account = new CheckingAccount() { CustomerId = customerId }; checkingAccountRepository.Add(account); }   account.Balance = account.Balance + amount; if (account.Balance < 0) throw new ApplicationException("Overdraft not accepted");   bankDbContext.SaveChanges(); } } public void WithdrawAmount(int customerId, decimal amount) { DepositAmount(customerId, -1*amount); } } }   BankServiceHost The host acts as a glue binding contracts with it’s services, exposing the endpoints. The services can be exposed either through the code or configuration file, configuration file is preferred as it allows run time changes to service behavior even after deployment. We have 3 services and for each of the service you need to define name (the class that implements the service with fully qualified namespace) and endpoint known as ABC, i.e. address, binding and contract. We are using netTcpBinding and have defined the base address with for each of the contracts .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } <system.serviceModel> <services> <service name="ProfileService.Profile"> <endpoint binding="netTcpBinding" contract="ProfileContract.IProfile"/> <host> <baseAddresses> <add baseAddress="net.tcp://localhost:1000/Profile"/> </baseAddresses> </host> </service> <service name="CheckingAccountService.Checking"> <endpoint binding="netTcpBinding" contract="CheckingAccountContract.ICheckingAccount"/> <host> <baseAddresses> <add baseAddress="net.tcp://localhost:1000/Checking"/> </baseAddresses> </host> </service> <service name="SavingsAccountService.Savings"> <endpoint binding="netTcpBinding" contract="SavingsAccountContract.ISavingsAccount"/> <host> <baseAddresses> <add baseAddress="net.tcp://localhost:1000/Savings"/> </baseAddresses> </host> </service> </services> </system.serviceModel> Have to open the services by creating service host which will handle the incoming requests from clients.   using System;   namespace ServiceHost { class Program { static void Main(string[] args) { CreateHosts(); Console.ReadLine(); }   private static void CreateHosts() { CreateHost(typeof(ProfileService.Profile),"Profile Service"); CreateHost(typeof(SavingsAccountService.Savings), "Savings Account Service"); CreateHost(typeof(CheckingAccountService.Checking), "Checking Account Service"); }   private static void CreateHost(Type type, string hostDescription) { System.ServiceModel.ServiceHost host = new System.ServiceModel.ServiceHost(type); host.Open();   if (host.ChannelDispatchers != null && host.ChannelDispatchers.Count != 0 && host.ChannelDispatchers[0].Listener != null) Console.WriteLine("Started: " + host.ChannelDispatchers[0].Listener.Uri); else Console.WriteLine("Failed to start:" + hostDescription); } } } BankClient    The client has no knowledge about service business logic other than the functionality it exposes through the contract, end points and a proxy to work against. The endpoint data and server proxy can be generated by right clicking on the project reference and choosing ‘Add Service Reference’ and entering the service end point address. Or if you have access to source, you can manually reference contract dlls and update clients configuration file to point to the service end point if the server and client happens to be being built using .Net framework. One of the pros with the manual approach is you don’t have to work against messy code generated files.   <system.serviceModel> <client> <endpoint name="tcpProfile" address="net.tcp://localhost:1000/Profile" binding="netTcpBinding" contract="ProfileContract.IProfile"/> <endpoint name="tcpCheckingAccount" address="net.tcp://localhost:1000/Checking" binding="netTcpBinding" contract="CheckingAccountContract.ICheckingAccount"/> <endpoint name="tcpSavingsAccount" address="net.tcp://localhost:1000/Savings" binding="netTcpBinding" contract="SavingsAccountContract.ISavingsAccount"/>   </client> </system.serviceModel> The client uses a façade to connect to the services   using System.ServiceModel; using CheckingAccountContract; using ProfileContract; using SavingsAccountContract;   namespace Client { public class ProxyFacade { public static IProfile ProfileProxy() { return (new ChannelFactory<IProfile>("tcpProfile")).CreateChannel(); }   public static ICheckingAccount CheckingAccountProxy() { return (new ChannelFactory<ICheckingAccount>("tcpCheckingAccount")) .CreateChannel(); }   public static ISavingsAccount SavingsAccountProxy() { return (new ChannelFactory<ISavingsAccount>("tcpSavingsAccount")) .CreateChannel(); }   } }   With that in place, lets get our unit tests going   using System; using System.Diagnostics; using BankDAL.Model; using NUnit.Framework; using ProfileContract;   namespace Client { [TestFixture] public class Tests { private void TransferFundsFromSavingsToCheckingAccount(int customerId, decimal amount) { ProxyFacade.CheckingAccountProxy().DepositAmount(customerId, amount); ProxyFacade.SavingsAccountProxy().WithdrawAmount(customerId, amount); }   private void TransferFundsFromCheckingToSavingsAccount(int customerId, decimal amount) { ProxyFacade.SavingsAccountProxy().DepositAmount(customerId, amount); ProxyFacade.CheckingAccountProxy().WithdrawAmount(customerId, amount); }     [Test] public void CreateAndGetProfileTest() { IProfile profile = ProxyFacade.ProfileProxy(); const string customerName = "Tom"; int customerId = profile.CreateCustomer(customerName, "NJ", new DateTime(1982, 1, 1)).Id; Customer customer = profile.GetCustomer(customerId); Assert.AreEqual(customerName,customer.FullName); }   [Test] public void DepositWithDrawAndTransferAmountTest() { IProfile profile = ProxyFacade.ProfileProxy(); string customerName = "Smith" + DateTime.Now.ToString("HH:mm:ss"); var customer = profile.CreateCustomer(customerName, "NJ", new DateTime(1982, 1, 1)); // Deposit to Savings ProxyFacade.SavingsAccountProxy().DepositAmount(customer.Id, 100); ProxyFacade.SavingsAccountProxy().DepositAmount(customer.Id, 25); Assert.AreEqual(125, ProxyFacade.SavingsAccountProxy().GetSavingsAccountBalance(customer.Id)); // Withdraw ProxyFacade.SavingsAccountProxy().WithdrawAmount(customer.Id, 30); Assert.AreEqual(95, ProxyFacade.SavingsAccountProxy().GetSavingsAccountBalance(customer.Id));   // Deposit to Checking ProxyFacade.CheckingAccountProxy().DepositAmount(customer.Id, 60); ProxyFacade.CheckingAccountProxy().DepositAmount(customer.Id, 40); Assert.AreEqual(100, ProxyFacade.CheckingAccountProxy().GetCheckingAccountBalance(customer.Id)); // Withdraw ProxyFacade.CheckingAccountProxy().WithdrawAmount(customer.Id, 30); Assert.AreEqual(70, ProxyFacade.CheckingAccountProxy().GetCheckingAccountBalance(customer.Id));   // Transfer from Savings to Checking TransferFundsFromSavingsToCheckingAccount(customer.Id,10); Assert.AreEqual(85, ProxyFacade.SavingsAccountProxy().GetSavingsAccountBalance(customer.Id)); Assert.AreEqual(80, ProxyFacade.CheckingAccountProxy().GetCheckingAccountBalance(customer.Id));   // Transfer from Checking to Savings TransferFundsFromCheckingToSavingsAccount(customer.Id, 50); Assert.AreEqual(135, ProxyFacade.SavingsAccountProxy().GetSavingsAccountBalance(customer.Id)); Assert.AreEqual(30, ProxyFacade.CheckingAccountProxy().GetCheckingAccountBalance(customer.Id)); }   [Test] public void FundTransfersWithOverDraftTest() { IProfile profile = ProxyFacade.ProfileProxy(); string customerName = "Angelina" + DateTime.Now.ToString("HH:mm:ss");   var customerId = profile.CreateCustomer(customerName, "NJ", new DateTime(1972, 1, 1)).Id;   ProxyFacade.SavingsAccountProxy().DepositAmount(customerId, 100); TransferFundsFromSavingsToCheckingAccount(customerId,80); Assert.AreEqual(20, ProxyFacade.SavingsAccountProxy().GetSavingsAccountBalance(customerId)); Assert.AreEqual(80, ProxyFacade.CheckingAccountProxy().GetCheckingAccountBalance(customerId));   try { TransferFundsFromSavingsToCheckingAccount(customerId,30); } catch (Exception e) { Debug.WriteLine(e.Message); }   Assert.AreEqual(110, ProxyFacade.CheckingAccountProxy().GetCheckingAccountBalance(customerId)); Assert.AreEqual(20, ProxyFacade.SavingsAccountProxy().GetSavingsAccountBalance(customerId)); } } }   We are creating a new instance of the channel for every operation, we will look into instance management and how creating a new instance of channel affects it in subsequent articles. The first two test cases deals with creation of Customer, deposit and withdraw of month between accounts. The last case, FundTransferWithOverDraftTest() is interesting. Customer starts with depositing $100 in SavingsAccount followed by transfer of $80 in to checking account resulting in $20 in savings account.  Customer then initiates $30 transfer from Savings to Checking resulting in overdraft exception on Savings with $30 being deposited to Checking. As we are not running both the requests in transactions the customer ends up with more amount than what he started with $100. In subsequent posts we will look into transactions handling.  Make sure the ServiceHost project is set as start up project and start the solution. Run the test cases either from NUnit client or TestDriven.Net/Resharper which ever is your favorite tool. Make sure you have updated the data base connection string in the ServiceHost config file to point to your local database

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  • Maven: Unresolved references to [org.osgi.service.http]

    - by Simone Vellei
    I'm trying to create a bundle using HttpService for register Servlet using maven-bundle-plugin. The pom.xml of the project is: <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>felix-tutorial</groupId> <artifactId>example-1</artifactId> <version>1.0</version> <packaging>bundle</packaging> <name>Apache Felix Tutorial Example 1</name> <description>Apache Felix Tutorial Example 1</description> <!-- Build Configuration --> <build> <plugins> <plugin> <groupId>org.apache.felix</groupId> <artifactId>maven-bundle-plugin</artifactId> <extensions>true</extensions> <configuration> <instructions> <Bundle-SymbolicName>${pom.groupId}.${pom.artifactId}</Bundle-SymbolicName> <Bundle-Name>Service listener example</Bundle-Name> <Bundle-Description>A bundle that displays messages at startup and when service events occur</Bundle-Description> <Bundle-Vendor>Apache Felix</Bundle-Vendor> <Bundle-Version>1.0.0</Bundle-Version> <Bundle-Activator>tutorial.example1.Activator</Bundle-Activator> <Import-Package>org.osgi.framework;version="1.0.0", javax.servlet, javax.servlet.http</Import-Package> </instructions> </configuration> </plugin> </plugins> </build> <!-- Dependecies Management --> <dependencies> <dependency> <groupId>org.apache.felix</groupId> <artifactId>org.apache.felix.framework</artifactId> <version>2.0.4</version> </dependency> <dependency> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>4.8.1</version> <scope>test</scope> </dependency> <dependency> <groupId>org.apache.felix</groupId> <artifactId>org.apache.felix.http.api</artifactId> <version>2.0.4</version> </dependency> <dependency> <groupId>org.apache.felix</groupId> <artifactId>org.apache.felix.http.base</artifactId> <version>2.0.4</version> </dependency> <dependency> <groupId>org.apache.felix</groupId> <artifactId>org.apache.felix.http.bridge</artifactId> <version>2.0.4</version> </dependency> <dependency> <groupId>org.apache.felix</groupId> <artifactId>org.apache.felix.http.bundle</artifactId> <version>2.0.4</version> </dependency> <dependency> <groupId>org.apache.felix</groupId> <artifactId>org.apache.felix.http.proxy</artifactId> <version>2.0.4</version> </dependency> <dependency> <groupId>org.apache.felix</groupId> <artifactId>org.apache.felix.http.whiteboard</artifactId> <version>2.0.4</version> </dependency> <dependency> <groupId>org.osgi</groupId> <artifactId>osgi_R4_compendium</artifactId> <version>1.0</version> </dependency> </dependencies> </project> "mvn install" command returns the following error: [INFO] Scanning for projects... [INFO] ------------------------------------------------------------------------ [INFO] Building Apache Felix Tutorial Example 1 [INFO] task-segment: [install] [INFO] ------------------------------------------------------------------------ Downloading: http://repo1.maven.org/maven2/org/apache/maven/plugins/maven-resources-plugin/2.3/maven-resources-plugin-2.3.pom Downloading: http://repo1.maven.org/maven2/org/apache/maven/plugins/maven-resources-plugin/2.3/maven-resources-plugin-2.3.jar Downloading: http://repo1.maven.org/maven2/org/apache/maven/plugins/maven-install-plugin/2.2/maven-install-plugin-2.2.pom Downloading: http://repo1.maven.org/maven2/org/apache/maven/plugins/maven-install-plugin/2.2/maven-install-plugin-2.2.jar Downloading: http://repo1.maven.org/maven2/org/apache/maven/shared/maven-filtering/1.0-beta-2/maven-filtering-1.0-beta-2.pom Downloading: http://repo1.maven.org/maven2/org/codehaus/plexus/plexus-interpolation/1.6/plexus-interpolation-1.6.pom Downloading: http://repo1.maven.org/maven2/org/codehaus/plexus/plexus-interpolation/1.6/plexus-interpolation-1.6.jar Downloading: http://repo1.maven.org/maven2/org/apache/maven/shared/maven-filtering/1.0-beta-2/maven-filtering-1.0-beta-2.jar [INFO] [resources:resources {execution: default-resources}] [WARNING] Using platform encoding (Cp1252 actually) to copy filtered resources, i.e. build is platform dependent! [INFO] skip non existing resourceDirectory C:\eclipse\ws\stripes-bundle\src\main\resources [INFO] [compiler:compile {execution: default-compile}] [INFO] Nothing to compile - all classes are up to date [INFO] [resources:testResources {execution: default-testResources}] [WARNING] Using platform encoding (Cp1252 actually) to copy filtered resources, i.e. build is platform dependent! [INFO] skip non existing resourceDirectory C:\eclipse\ws\stripes-bundle\src\test\resources [INFO] [compiler:testCompile {execution: default-testCompile}] [INFO] Nothing to compile - all classes are up to date [INFO] [surefire:test {execution: default-test}] [INFO] Surefire report directory: C:\eclipse\ws\stripes-bundle\target\surefire-reports ------------------------------------------------------- T E S T S ------------------------------------------------------- Running com.beanopoly.stripes.AppTest Tests run: 1, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.031 sec Results : Tests run: 1, Failures: 0, Errors: 0, Skipped: 0 [INFO] [bundle:bundle {execution: default-bundle}] [ERROR] Error building bundle felix-tutorial:example-1:bundle:1.0 : Unresolved references to [org.osgi.service.http] by class(es) on the Bundle-Classpath[Jar:do [ERROR] Error(s) found in bundle configuration [INFO] ------------------------------------------------------------------------ [ERROR] BUILD ERROR [INFO] ------------------------------------------------------------------------ [INFO] Error(s) found in bundle configuration [INFO] ------------------------------------------------------------------------ [INFO] For more information, run Maven with the -e switch [INFO] ------------------------------------------------------------------------ [INFO] Total time: 12 seconds [INFO] Finished at: Sat Mar 27 13:11:47 CET 2010 [INFO] Final Memory: 12M/21M [INFO] ------------------------------------------------------------------------

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  • Why is my simple recusive method for this game always off by 1?

    - by FrankTheTank
    I'm attempting to create a text-based version of this game: http://www.cse.nd.edu/java/SameGame.html Here is the code I have so far: #include <iostream> #include <vector> #include <ctime> class Clickomania { public: Clickomania(); std::vector<std::vector<int> > board; int move(int, int); bool isSolved(); void print(); void pushDown(); bool isValid(); }; Clickomania::Clickomania() : board(12, std::vector<int>(8,0)) { srand((unsigned)time(0)); for(int i = 0; i < 12; i++) { for(int j = 0; j < 8; j++) { int color = (rand() % 3) + 1; board[i][j] = color; } } } void Clickomania::pushDown() { for(int i = 0; i < 8; i++) { for(int j = 0; j < 12; j++) { if (board[j][i] == 0) { for(int k = j; k > 0; k--) { board[k][i] = board[k-1][i]; } board[0][i] = 0; } } } } int Clickomania::move(int row, int col) { bool match = false; int totalMatches = 0; if (row > 12 || row < 0 || col > 8 || col < 0) { return 0; } int currentColor = board[row][col]; board[row][col] = 0; if ((row + 1) < 12) { if (board[row+1][col] == currentColor) { match = true; totalMatches++; totalMatches += move(row+1, col); } } if ((row - 1) >= 0) { if (board[row-1][col] == currentColor) { match = true; totalMatches++; totalMatches += move(row-1, col); } } if ((col + 1) < 8) { if (board[row][col+1] == currentColor) { match = true; totalMatches++; totalMatches += move(row, col+1); } } if ((col - 1) >= 0) { if (board[row][col-1] == currentColor) { match = true; totalMatches++; totalMatches += move(row, col-1); } } return totalMatches; } void Clickomania::print() { for(int i = 0; i < 12; i++) { for(int j = 0; j < 8; j++) { std::cout << board[i][j]; } std::cout << "\n"; } } int main() { Clickomania game; game.print(); int row; int col; std::cout << "Enter row: "; std::cin >> row; std::cout << "Enter col: "; std::cin >> col; int numDestroyed = game.move(row,col); game.print(); std::cout << "Destroyed: " << numDestroyed << "\n"; } The method that is giving me trouble is my "move" method. This method, given a pair of coordinates, should delete all the squares at that coordinate with the same number and likewise with all the squares with the same number connected to it. If you play the link I gave above you'll see how the deletion works on a click. int Clickomania::move(int row, int col) { bool match = false; int totalMatches = 0; if (row > 12 || row < 0 || col > 8 || col < 0) { return 0; } int currentColor = board[row][col]; board[row][col] = 0; if ((row + 1) < 12) { if (board[row+1][col] == currentColor) { match = true; totalMatches++; totalMatches += move(row+1, col); } } if ((row - 1) >= 0) { if (board[row-1][col] == currentColor) { match = true; totalMatches++; totalMatches += move(row-1, col); } } if ((col + 1) < 8) { if (board[row][col+1] == currentColor) { match = true; totalMatches++; totalMatches += move(row, col+1); } } if ((col - 1) >= 0) { if (board[row][col-1] == currentColor) { match = true; totalMatches++; totalMatches += move(row, col-1); } } return totalMatches; } My move() method above works fine, as in, it will delete the appropriate "blocks" and replace them with zeros. However, the number of destroyed (value returned) is always one off (too small). I believe this is because the first call of move() isn't being counted but I don't know how to differentiate between the first call or subsequent calls in that recursive method. How can I modify my move() method so it returns the correct number of destroyed blocks?

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  • TSQL Conditionally Select Specific Value

    - by Dzejms
    This is a follow-up to #1644748 where I successfully answered my own question, but Quassnoi helped me to realize that it was the wrong question. He gave me a solution that worked for my sample data, but I couldn't plug it back into the parent stored procedure because I fail at SQL 2005 syntax. So here is an attempt to paint the broader picture and ask what I actually need. This is part of a stored procedure that returns a list of items in a bug tracking application I've inherited. There are are over 100 fields and 26 joins so I'm pulling out only the mostly relevant bits. SELECT tickets.ticketid, tickets.tickettype, tickets_tickettype_lu.tickettypedesc, tickets.stage, tickets.position, tickets.sponsor, tickets.dev, tickets.qa, DATEDIFF(DAY, ticket_history_assignment.savedate, GETDATE()) as 'daysinqueue' FROM dbo.tickets WITH (NOLOCK) LEFT OUTER JOIN dbo.tickets_tickettype_lu WITH (NOLOCK) ON tickets.tickettype = tickets_tickettype_lu.tickettypeid LEFT OUTER JOIN dbo.tickets_history_assignment WITH (NOLOCK) ON tickets_history_assignment.ticketid = tickets.ticketid AND tickets_history_assignment.historyid = ( SELECT MAX(historyid) FROM dbo.tickets_history_assignment WITH (NOLOCK) WHERE tickets_history_assignment.ticketid = tickets.ticketid GROUP BY tickets_history_assignment.ticketid ) WHERE tickets.sponsor = @sponsor The area of interest is the daysinqueue subquery mess. The tickets_history_assignment table looks roughly as follows declare @tickets_history_assignment table ( historyid int, ticketid int, sponsor int, dev int, qa int, savedate datetime ) insert into @tickets_history_assignment values (1521402, 92774,20,14, 20, '2009-10-27 09:17:59.527') insert into @tickets_history_assignment values (1521399, 92774,20,14, 42, '2009-08-31 12:07:52.917') insert into @tickets_history_assignment values (1521311, 92774,100,14, 42, '2008-12-08 16:15:49.887') insert into @tickets_history_assignment values (1521336, 92774,100,14, 42, '2009-01-16 14:27:43.577') Whenever a ticket is saved, the current values for sponsor, dev and qa are stored in the tickets_history_assignment table with the ticketid and a timestamp. So it is possible for someone to change the value for qa, but leave sponsor alone. What I want to know, based on all of these conditions, is the historyid of the record in the tickets_history_assignment table where the sponsor value was last changed so that I can calculate the value for daysinqueue. If a record is inserted into the history table, and only the qa value has changed, I don't want that record. So simply relying on MAX(historyid) won't work for me. Quassnoi came up with the following which seemed to work with my sample data, but I can't plug it into the larger query, SQL Manager bitches about the WITH statement. ;WITH rows AS ( SELECT *, ROW_NUMBER() OVER (PARTITION BY ticketid ORDER BY savedate DESC) AS rn FROM @Table ) SELECT rl.sponsor, ro.savedate FROM rows rl CROSS APPLY ( SELECT TOP 1 rc.savedate FROM rows rc JOIN rows rn ON rn.ticketid = rc.ticketid AND rn.rn = rc.rn + 1 AND rn.sponsor <> rc.sponsor WHERE rc.ticketid = rl.ticketid ORDER BY rc.rn ) ro WHERE rl.rn = 1 I played with it yesterday afternoon and got nowhere because I don't fundamentally understand what is going on here and how it should fit into the larger context. So, any takers? UPDATE Ok, here's the whole thing. I've been switching some of the table and column names in an attempt to simplify things so here's the full unedited mess. snip - old bad code Here are the errors: Msg 102, Level 15, State 1, Procedure usp_GetProjectRecordsByAssignment, Line 159 Incorrect syntax near ';'. Msg 102, Level 15, State 1, Procedure usp_GetProjectRecordsByAssignment, Line 179 Incorrect syntax near ')'. Line numbers are of course not correct but refer to ;WITH rows AS And the ')' char after the WHERE rl.rn = 1 ) Respectively Is there a tag for extra super long question? UPDATE #2 Here is the finished query for anyone who may need this: CREATE PROCEDURE [dbo].[usp_GetProjectRecordsByAssignment] ( @assigned numeric(18,0), @assignedtype numeric(18,0) ) AS SET NOCOUNT ON WITH rows AS ( SELECT *, ROW_NUMBER() OVER (PARTITION BY recordid ORDER BY savedate DESC) AS rn FROM projects_history_assignment ) SELECT projects_records.recordid, projects_records.recordtype, projects_recordtype_lu.recordtypedesc, projects_records.stage, projects_stage_lu.stagedesc, projects_records.position, projects_position_lu.positiondesc, CASE projects_records.clientrequested WHEN '1' THEN 'Yes' WHEN '0' THEN 'No' END AS clientrequested, projects_records.reportingmethod, projects_reportingmethod_lu.reportingmethoddesc, projects_records.clientaccess, projects_clientaccess_lu.clientaccessdesc, projects_records.clientnumber, projects_records.project, projects_lu.projectdesc, projects_records.version, projects_version_lu.versiondesc, projects_records.projectedversion, projects_version_lu_projected.versiondesc AS projectedversiondesc, projects_records.sitetype, projects_sitetype_lu.sitetypedesc, projects_records.title, projects_records.module, projects_module_lu.moduledesc, projects_records.component, projects_component_lu.componentdesc, projects_records.loginusername, projects_records.loginpassword, projects_records.assistedusername, projects_records.browsername, projects_browsername_lu.browsernamedesc, projects_records.browserversion, projects_records.osname, projects_osname_lu.osnamedesc, projects_records.osversion, projects_records.errortype, projects_errortype_lu.errortypedesc, projects_records.gsipriority, projects_gsipriority_lu.gsiprioritydesc, projects_records.clientpriority, projects_clientpriority_lu.clientprioritydesc, projects_records.scheduledstartdate, projects_records.scheduledcompletiondate, projects_records.projectedhours, projects_records.actualstartdate, projects_records.actualcompletiondate, projects_records.actualhours, CASE projects_records.billclient WHEN '1' THEN 'Yes' WHEN '0' THEN 'No' END AS billclient, projects_records.billamount, projects_records.status, projects_status_lu.statusdesc, CASE CAST(projects_records.assigned AS VARCHAR(5)) WHEN '0' THEN 'N/A' WHEN '10000' THEN 'Unassigned' WHEN '20000' THEN 'Client' WHEN '30000' THEN 'Tech Support' WHEN '40000' THEN 'LMI Tech Support' WHEN '50000' THEN 'Upload' WHEN '60000' THEN 'Spider' WHEN '70000' THEN 'DB Admin' ELSE rtrim(users_assigned.nickname) + ' ' + rtrim(users_assigned.lastname) END AS assigned, CASE CAST(projects_records.assigneddev AS VARCHAR(5)) WHEN '0' THEN 'N/A' WHEN '10000' THEN 'Unassigned' ELSE rtrim(users_assigneddev.nickname) + ' ' + rtrim(users_assigneddev.lastname) END AS assigneddev, CASE CAST(projects_records.assignedqa AS VARCHAR(5)) WHEN '0' THEN 'N/A' WHEN '10000' THEN 'Unassigned' ELSE rtrim(users_assignedqa.nickname) + ' ' + rtrim(users_assignedqa.lastname) END AS assignedqa, CASE CAST(projects_records.assignedsponsor AS VARCHAR(5)) WHEN '0' THEN 'N/A' WHEN '10000' THEN 'Unassigned' ELSE rtrim(users_assignedsponsor.nickname) + ' ' + rtrim(users_assignedsponsor.lastname) END AS assignedsponsor, projects_records.clientcreated, CASE projects_records.clientcreated WHEN '1' THEN 'Yes' WHEN '0' THEN 'No' END AS clientcreateddesc, CASE projects_records.clientcreated WHEN '1' THEN rtrim(clientusers_createuser.firstname) + ' ' + rtrim(clientusers_createuser.lastname) + ' (Client)' ELSE rtrim(users_createuser.nickname) + ' ' + rtrim(users_createuser.lastname) END AS createuser, projects_records.createdate, projects_records.savedate, projects_resolution.sitesaffected, projects_sitesaffected_lu.sitesaffecteddesc, DATEDIFF(DAY, projects_history_assignment.savedate, GETDATE()) as 'daysinqueue', projects_records.iOnHitList, projects_records.changetype FROM dbo.projects_records WITH (NOLOCK) LEFT OUTER JOIN dbo.projects_recordtype_lu WITH (NOLOCK) ON projects_records.recordtype = projects_recordtype_lu.recordtypeid LEFT OUTER JOIN dbo.projects_stage_lu WITH (NOLOCK) ON projects_records.stage = projects_stage_lu.stageid LEFT OUTER JOIN dbo.projects_position_lu WITH (NOLOCK) ON projects_records.position = projects_position_lu.positionid LEFT OUTER JOIN dbo.projects_reportingmethod_lu WITH (NOLOCK) ON projects_records.reportingmethod = projects_reportingmethod_lu.reportingmethodid LEFT OUTER JOIN dbo.projects_lu WITH (NOLOCK) ON projects_records.project = projects_lu.projectid LEFT OUTER JOIN dbo.projects_version_lu WITH (NOLOCK) ON projects_records.version = projects_version_lu.versionid LEFT OUTER JOIN dbo.projects_version_lu projects_version_lu_projected WITH (NOLOCK) ON projects_records.projectedversion = projects_version_lu_projected.versionid LEFT OUTER JOIN dbo.projects_sitetype_lu WITH (NOLOCK) ON projects_records.sitetype = projects_sitetype_lu.sitetypeid LEFT OUTER JOIN dbo.projects_module_lu WITH (NOLOCK) ON projects_records.module = projects_module_lu.moduleid LEFT OUTER JOIN dbo.projects_component_lu WITH (NOLOCK) ON projects_records.component = projects_component_lu.componentid LEFT OUTER JOIN dbo.projects_browsername_lu WITH (NOLOCK) ON projects_records.browsername = projects_browsername_lu.browsernameid LEFT OUTER JOIN dbo.projects_osname_lu WITH (NOLOCK) ON projects_records.osname = projects_osname_lu.osnameid LEFT OUTER JOIN dbo.projects_errortype_lu WITH (NOLOCK) ON projects_records.errortype = projects_errortype_lu.errortypeid LEFT OUTER JOIN dbo.projects_resolution WITH (NOLOCK) ON projects_records.recordid = projects_resolution.recordid LEFT OUTER JOIN dbo.projects_sitesaffected_lu WITH (NOLOCK) ON projects_resolution.sitesaffected = projects_sitesaffected_lu.sitesaffectedid LEFT OUTER JOIN dbo.projects_gsipriority_lu WITH (NOLOCK) ON projects_records.gsipriority = projects_gsipriority_lu.gsipriorityid LEFT OUTER JOIN dbo.projects_clientpriority_lu WITH (NOLOCK) ON projects_records.clientpriority = projects_clientpriority_lu.clientpriorityid LEFT OUTER JOIN dbo.projects_status_lu WITH (NOLOCK) ON projects_records.status = projects_status_lu.statusid LEFT OUTER JOIN dbo.projects_clientaccess_lu WITH (NOLOCK) ON projects_records.clientaccess = projects_clientaccess_lu.clientaccessid LEFT OUTER JOIN dbo.users users_assigned WITH (NOLOCK) ON projects_records.assigned = users_assigned.userid LEFT OUTER JOIN dbo.users users_assigneddev WITH (NOLOCK) ON projects_records.assigneddev = users_assigneddev.userid LEFT OUTER JOIN dbo.users users_assignedqa WITH (NOLOCK) ON projects_records.assignedqa = users_assignedqa.userid LEFT OUTER JOIN dbo.users users_assignedsponsor WITH (NOLOCK) ON projects_records.assignedsponsor = users_assignedsponsor.userid LEFT OUTER JOIN dbo.users users_createuser WITH (NOLOCK) ON projects_records.createuser = users_createuser.userid LEFT OUTER JOIN dbo.clientusers clientusers_createuser WITH (NOLOCK) ON projects_records.createuser = clientusers_createuser.userid LEFT OUTER JOIN dbo.projects_history_assignment WITH (NOLOCK) ON projects_history_assignment.recordid = projects_records.recordid AND projects_history_assignment.historyid = ( SELECT ro.historyid FROM rows rl CROSS APPLY ( SELECT TOP 1 rc.historyid FROM rows rc JOIN rows rn ON rn.recordid = rc.recordid AND rn.rn = rc.rn + 1 AND rn.assigned <> rc.assigned WHERE rc.recordid = rl.recordid ORDER BY rc.rn ) ro WHERE rl.rn = 1 AND rl.recordid = projects_records.recordid ) WHERE (@assignedtype='0' and projects_records.assigned = @assigned) OR (@assignedtype='1' and projects_records.assigneddev = @assigned) OR (@assignedtype='2' and projects_records.assignedqa = @assigned) OR (@assignedtype='3' and projects_records.assignedsponsor = @assigned) OR (@assignedtype='4' and projects_records.createuser = @assigned)

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  • getelementbyid does not work in firefox

    - by gaurab
    hi, this below mentioned code works perfect in internet explorer but not in firefox... i get an error in line in firefox: document.getElementById("supplier_no").value= values_array[0]; that getElementById returns null. how to solve the problem? var winName; //variable for the popup window var g_return_destination = null ; //variable to track where the data gets sent back to. // Set the value in the original pages text box. function f_set_home_value( as_Value ) { if (document.getElementById(g_return_destination[0]).name == "netbank_supplier_name_info" ) { //clear the old values for (selnum = 1; selnum <= 5; selnum++) { document.getElementById("expense_account"+selnum).value = ""; document.getElementById("expense_account_name"+selnum).value = ""; document.getElementById("expense_vat_flag"+selnum).value = "off"; document.getElementById("expense_vat_flag"+selnum).checked = ""; document.getElementById("expense_vat_amount"+selnum).value = ""; document.getElementById("expense_vat_code"+selnum).value = ""; document.getElementById("expense_period"+selnum).value = ""; document.getElementById("expense_date"+selnum).value = ""; if (selnum!=1) {//these are sometimes defaulted in, and in any case you will always have line1 document.getElementById("expense_more_dept"+selnum).value = ""; document.getElementById("expense_more_prj"+selnum).value = ""; document.getElementById("expense_more_subj"+selnum).value = ""; } document.getElementById("expense_amount"+selnum).value = ""; } var values_array = as_Value[0].split("!"); document.getElementById("supplier_no").value= values_array[0]; document.getElementById("supplier_bankAccount_no").value= values_array[1]; str = values_array[2] ; str = str.split(";sp;").join(" "); document.getElementById("default_expense_account").value= str; document.getElementById("expense_account1").value= str; document.getElementById("expense_more_sok1").disabled= false; str = values_array[3] ; str = str.split(";sp;").join(" "); document.getElementById("payment_term").value= str; strPeriod = calcPeriod(str,document.getElementById("due_date").value); document.getElementById("expense_period1").value = (strPeriod); strExpenseDate = calcExpenseDate(str,document.getElementById("due_date").value); document.getElementById("expense_date1").value = (strExpenseDate); str = values_array[4] ; str = str.split(";sp;").join(" "); document.getElementById("expense_account_name1").value= str; str = values_array[5] ; str = str.split(";sp;").join(" "); document.getElementById("expense_vat_code1").value= str; if (str == 0) { document.getElementById("expense_vat_flag1").checked= ''; document.getElementById("expense_vat_flag1").disabled= true; }else{ document.getElementById("expense_vat_flag1").checked= 'yes'; document.getElementById("expense_vat_flag1").value= 'on'; document.getElementById("expense_vat_flag1").disabled= false; } str = values_array[6] ; str = str.split(";sp;").join(" "); document.getElementById("supplier_name").value= str; var str = values_array[7]; str = str.split(";sp;").join(" "); str = str.split("&cr;").join("\r"); document.getElementById("netbank_supplier_name_info").value= str; strx = justNumberNF(document.getElementById("amount").value); document.all["expense_vat_amount1"].value = NetbankToDollarsAndCents(strx * (24/124)) ; document.getElementById("amount").value=NetbankToDollarsAndCents(strx); document.getElementById("expense_amount1").value = document.getElementById("amount").value; document.getElementById("expense_amount2").value = ''; document.getElementById("expense_account2").value= ''; //document.getElementById("expense_vat_flag2").value= ''; document.getElementById("expense_vat_amount2").value= ''; document.getElementById("expense_amount3").value = ''; document.getElementById("expense_account3").value= ''; //.getElementById("expense_vat_flag3").value= ''; document.getElementById("expense_vat_amount3").value= ''; document.getElementById("expense_amount4").value = ''; document.getElementById("expense_account4").value= ''; //document.getElementById("expense_vat_flag4").value= ''; document.getElementById("expense_vat_amount4").value= ''; document.getElementById("expense_amount5").value = ''; document.getElementById("expense_account5").value= ''; //document.getElementById("expense_vat_flag5").value= ''; document.getElementById("expense_vat_amount5").value= ''; str = values_array[8] ; str = str.split(";sp;").join(" "); if (str=="2"){ document.frmName.ButtonSelPeriodisering1.disabled=false; document.frmName.ButtonSelPeriodisering1.click(); } winName.close(); } } //Pass Data Back to original window function f_popup_return(as_Value) { var l_return = new Array(1); l_return[0] = as_Value; f_set_home_value(l_return); } function justNumberNF(val){ val = (val==null) ? 0 : val; // check if a number, otherwise try taking out non-number characters. if (isNaN(val)) { var newVal = parseFloat(val.replace(/[^\d\.\-]/g, '.')); // check if still not a number. Might be undefined, '', etc., so just replace with 0. return (isNaN(newVal) ? 0 : newVal); } // return 0 in place of infinite numbers. else if (!isFinite(val)) { return 0; } return val; }; function NetbankToDollarsAndCents(n) { var s = "" + Math.round(n * 100) / 100 ; var i = s.indexOf('.') ; if (i < 0) {return s + ",00" } ; var t = s.substring(0, i + 1) + s.substring(i + 1, i + 3) ; if (i + 2 == s.length) {t += "0"} ; return t.replace('.',',') ; }

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  • SocketChannel in Java sends data, but it doesn't get to destination application

    - by Peterson
    Hi Everybody, I'm suffering a lot to create a simple ChatServer in Java, using the NIO libraries. Wonder if someone could help me. I am doing that by using SocketChannel and Selector to handle multiple clients in a single thread. The problem is: I am able to accept new connections and get it's data, but when I try to send data back, the SocketChannel simply doesn't work. In the method write(), it returns a integer that is the same size of the data i'm passing to it, but the client never receives that data. Strangely, when I close the server application, the client receives the data. It's like the socketchannel maintains a buffer, and it only get flushed when I close the application. Here are some more details, to give you more information to help. I'm handling the events in this piece of code: private void run() throws IOException { ServerSocketChannel ssc = ServerSocketChannel.open(); // Set it to non-blocking, so we can use select ssc.configureBlocking( false ); // Get the Socket connected to this channel, and bind it // to the listening port this.serverSocket = ssc.socket(); InetSocketAddress isa = new InetSocketAddress( this.port ); serverSocket.bind( isa ); // Create a new Selector for selecting this.masterSelector = Selector.open(); // Register the ServerSocketChannel, so we can // listen for incoming connections ssc.register( masterSelector, SelectionKey.OP_ACCEPT ); while (true) { // See if we've had any activity -- either // an incoming connection, or incoming data on an // existing connection int num = masterSelector.select(); // If we don't have any activity, loop around and wait // again if (num == 0) { continue; } // Get the keys corresponding to the activity // that has been detected, and process them // one by one Set keys = masterSelector.selectedKeys(); Iterator it = keys.iterator(); while (it.hasNext()) { // Get a key representing one of bits of I/O // activity SelectionKey key = (SelectionKey)it.next(); // What kind of activity is it? if ((key.readyOps() & SelectionKey.OP_ACCEPT) == SelectionKey.OP_ACCEPT) { // Aceita a conexão Socket s = serverSocket.accept(); System.out.println( "LOG: Conexao TCP aceita de " + s.getInetAddress() + ":" + s.getPort() ); // Make sure to make it non-blocking, so we can // use a selector on it. SocketChannel sc = s.getChannel(); sc.configureBlocking( false ); // Registra a conexao no seletor, apenas para leitura sc.register( masterSelector, SelectionKey.OP_READ ); } else if ( key.isReadable() ) { SocketChannel sc = null; // It's incoming data on a connection, so // process it sc = (SocketChannel)key.channel(); // Verifica se a conexão corresponde a um cliente já existente if((clientsMap.getClient(key)) != null){ boolean closedConnection = !processIncomingClientData(key); if(closedConnection){ int id = clientsMap.getClient(key); closeClient(id); } } else { boolean clientAccepted = processIncomingDataFromNewClient(key); if(!clientAccepted){ // Se o cliente não foi aceito, sua conexão é simplesmente fechada sc.socket().close(); sc.close(); key.cancel(); } } } } // We remove the selected keys, because we've dealt // with them. keys.clear(); } } This piece of code is simply handles new clients that wants to connect to the chat. So, a client makes a TCP connection to the server, and once it gets accepted, it sends data to the server following a simply text protocol, informing his id and asking to get registrated to the server. I handle this in the method processIncomingDataFromNewClient(key). I'm also keeping a map of clients and its connections in a data structure similar to a hashtable. I? doing that because I need to recover a client Id from a connection and a connection from a client Id. This is can be shown in: clientsMap.getClient(key). But the problem itself resides in the method processIncomingDataFromNewClient(key). There, I simply read the data that the client sent to me, validate it, and if it's ok, I send a message back to the client to tell that it is connected to the chat server. Here is a similar piece of code: private boolean processIncomingDataFromNewClient(SelectionKey key){ SocketChannel sc = (SocketChannel) key.channel(); String connectionOrigin = sc.socket().getInetAddress() + ":" + sc.socket().getPort(); int id = 0; //id of the client buf.clear(); int bytesRead = 0; try { bytesRead = sc.read(buf); if(bytesRead<=0){ System.out.println("Conexão fechada pelo: " + connectionOrigin); return false; } System.out.println("LOG: " + bytesRead + " bytes lidos de " + connectionOrigin); String msg = new String(buf.array(),0,bytesRead); // Do validations with the client sent me here // gets the client id }catch (Exception e) { e.printStackTrace(); System.out.println("LOG: Oops. Cliente não conhece o protocolo. Fechando a conexão: " + connectionOrigin); System.out.println("LOG: Primeiros 10 caracteres enviados pelo cliente: " + msg); return false; } } } catch (IOException e) { System.out.println("LOG: Erro ao ler dados da conexao: " + connectionOrigin); System.out.println("LOG: "+ e.getLocalizedMessage()); System.out.println("LOG: Fechando a conexão..."); return false; } // If it gets to here, the protocol is ok and we can add the client boolean inserted = clientsMap.addClient(key, id); if(!inserted){ System.out.println("LOG: Não foi possível adicionar o cliente. Ou ele já está conectado ou já têm clientes demais. Id: " + id); System.out.println("LOG: Fechando a conexão: " + connectionOrigin); return false; } System.out.println("LOG: Novo cliente conectado! Enviando mesnsagem de confirmação. Id: " + id + " Conexao: " + connectionOrigin); /* Here is the error */ sendMessage(id, "Servidor pet: connection accepted"); System.out.println("LOG: Novo cliente conectado! Id: " + id + " Conexao: " + connectionOrigin); return true; } And finally, the method sendMessage(SelectionKey key) looks like this: private void sendMessage(int destId, String msg) { Charset charset = Charset.forName("ISO-8859-1"); CharBuffer charBuffer = CharBuffer.wrap(msg, 0, msg.length()); ByteBuffer bf = charset.encode(charBuffer); //bf.flip(); int bytesSent = 0; SelectionKey key = clientsMap.getClient(destId); SocketChannel sc = (SocketChannel) key.channel(); try { / int total_bytes_sent = 0; while(total_bytes_sent < msg.length()){ bytesSent = sc.write(bf); total_bytes_sent += bytesSent; } System.out.println("LOG: Bytes enviados para o cliente " + destId + ": "+ total_bytes_sent + " Tamanho da mensagem: " + msg.length()); } catch (IOException e) { System.out.println("LOG: Erro ao mandar mensagem para: " + destId); System.out.println("LOG: " + e.getLocalizedMessage()); } } So, what is happening is that the server, when send a message, prints something like this: LOG: Bytes sent to the client: 28 Size of the message: 28 So, it tells that it sent the data, but the chat client keeps blocking, waiting in the recv() method. So, the data never gets to it. When I close the server application, though, all the data appears in the client. I wonder why. It is important to say that the client is in C and the server JAVA, and I'm running both in the same machine, an Ubuntu Guest in virtualbox under windows. I also run both under windows host and under linuxes hosts, and keep getting the same strange problem. I'm sorry for the great lenght of this question, but I already searched a lot of places for an answer, found a lot of tutorials and questions, including here at StackOverflow, but coundn't find a reasonable explanation. I am really not liking this Java NIO, and i saw a lot of people complaining about it too. I am thinking that if I had done that in C it would have been a lot easier :-D So, if someone could help me and even discuss this behavor, it would be great! :-) Thanks everybody in advance, Péterson

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  • storing session data in mysql using php is not retrieving the data properly from the tables.

    - by Ronedog
    I have a problem retrieving some data from the $_SESSION using php and mysql. I've commented out the line in php.ini that tells the server to use the "file" to store the session info so my database will be used. I have a class that I use to write the information to the database and its working fine. When the user passes their credentials the class gets instantiated and the $_SESSION vars get set, then the user gets redirected to the index page. The index.php page includes the file where the db session class is, which when instantiated calles session_start() and the session variables should be in $_SESSION, but when I do var_dump($_SESSION) there is nothing in the array. However, when I look at the data in mysql, all the session information is in there. Its acting like session_start() has not been called, but by instantiating the class it is. Any idea what could be wrong? Here's the HTML: <?php include_once "classes/phpsessions_db/class.dbsession.php"; //used for sessions var_dump($_SESSION); ?> <html> . . . </html> Here's the dbsession class: <?php error_reporting(E_ALL); class dbSession { function dbSession($gc_maxlifetime = "", $gc_probability = "", $gc_divisor = "") { // if $gc_maxlifetime is specified and is an integer number if ($gc_maxlifetime != "" && is_integer($gc_maxlifetime)) { // set the new value @ini_set('session.gc_maxlifetime', $gc_maxlifetime); } // if $gc_probability is specified and is an integer number if ($gc_probability != "" && is_integer($gc_probability)) { // set the new value @ini_set('session.gc_probability', $gc_probability); } // if $gc_divisor is specified and is an integer number if ($gc_divisor != "" && is_integer($gc_divisor)) { // set the new value @ini_set('session.gc_divisor', $gc_divisor); } // get session lifetime $this->sessionLifetime = ini_get("session.gc_maxlifetime"); //Added by AARON. cancel the session's auto start,important, without this the session var's don't show up on next pg. session_write_close(); // register the new handler session_set_save_handler( array(&$this, 'open'), array(&$this, 'close'), array(&$this, 'read'), array(&$this, 'write'), array(&$this, 'destroy'), array(&$this, 'gc') ); register_shutdown_function('session_write_close'); // start the session @session_start(); } function stop() { $new_sess_id = $this->regenerate_id(true); session_unset(); session_destroy(); return $new_sess_id; } function regenerate_id($return_val=false) { // saves the old session's id $oldSessionID = session_id(); // regenerates the id // this function will create a new session, with a new id and containing the data from the old session // but will not delete the old session session_regenerate_id(); // because the session_regenerate_id() function does not delete the old session, // we have to delete it manually //$this->destroy($oldSessionID); //ADDED by aaron // returns the new session id if($return_val) { return session_id(); } } function open($save_path, $session_name) { // global $gf; // $gf->debug_this($gf, "GF: Opening Session"); // change the next values to match the setting of your mySQL database $mySQLHost = "localhost"; $mySQLUsername = "user"; $mySQLPassword = "pass"; $mySQLDatabase = "sessions"; $link = mysql_connect($mySQLHost, $mySQLUsername, $mySQLPassword); if (!$link) { die ("Could not connect to database!"); } $dbc = mysql_select_db($mySQLDatabase, $link); if (!$dbc) { die ("Could not select database!"); } return true; } function close() { mysql_close(); return true; } function read($session_id) { $result = @mysql_query(" SELECT session_data FROM session_data WHERE session_id = '".$session_id."' AND http_user_agent = '".$_SERVER["HTTP_USER_AGENT"]."' AND session_expire > '".time()."' "); // if anything was found if (is_resource($result) && @mysql_num_rows($result) > 0) { // return found data $fields = @mysql_fetch_assoc($result); // don't bother with the unserialization - PHP handles this automatically return unserialize($fields["session_data"]); } // if there was an error return an empty string - this HAS to be an empty string return ""; } function write($session_id, $session_data) { // global $gf; // first checks if there is a session with this id $result = @mysql_query(" SELECT * FROM session_data WHERE session_id = '".$session_id."' "); // if there is if (@mysql_num_rows($result) > 0) { // update the existing session's data // and set new expiry time $result = @mysql_query(" UPDATE session_data SET session_data = '".serialize($session_data)."', session_expire = '".(time() + $this->sessionLifetime)."' WHERE session_id = '".$session_id."' "); // if anything happened if (@mysql_affected_rows()) { // return true return true; } } else // if this session id is not in the database { // $gf->debug_this($gf, "inside dbSession, trying to write to db because session id was NOT in db"); $sql = " INSERT INTO session_data ( session_id, http_user_agent, session_data, session_expire ) VALUES ( '".serialize($session_id)."', '".$_SERVER["HTTP_USER_AGENT"]."', '".$session_data."', '".(time() + $this->sessionLifetime)."' ) "; // insert a new record $result = @mysql_query($sql); // if anything happened if (@mysql_affected_rows()) { // return an empty string return ""; } } // if something went wrong, return false return false; } function destroy($session_id) { // deletes the current session id from the database $result = @mysql_query(" DELETE FROM session_data WHERE session_id = '".$session_id."' "); // if anything happened if (@mysql_affected_rows()) { // return true return true; } // if something went wrong, return false return false; } function gc($maxlifetime) { // it deletes expired sessions from database $result = @mysql_query(" DELETE FROM session_data WHERE session_expire < '".(time() - $maxlifetime)."' "); } } //End of Class $session = new dbsession(); ?>

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  • Help with Java Program for Prime numbers

    - by Ben
    Hello everyone, I was wondering if you can help me with this program. I have been struggling with it for hours and have just trashed my code because the TA doesn't like how I executed it. I am completely hopeless and if anyone can help me out step by step, I would greatly appreciate it. In this project you will write a Java program that reads a positive integer n from standard input, then prints out the first n prime numbers. We say that an integer m is divisible by a non-zero integer d if there exists an integer k such that m = k d , i.e. if d divides evenly into m. Equivalently, m is divisible by d if the remainder of m upon (integer) division by d is zero. We would also express this by saying that d is a divisor of m. A positive integer p is called prime if its only positive divisors are 1 and p. The one exception to this rule is the number 1 itself, which is considered to be non-prime. A positive integer that is not prime is called composite. Euclid showed that there are infinitely many prime numbers. The prime and composite sequences begin as follows: Primes: 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, … Composites: 1, 4, 6, 8, 9, 10, 12, 14, 15, 16, 18, 20, 21, 22, 24, 25, 26, 27, 28, … There are many ways to test a number for primality, but perhaps the simplest is to simply do trial divisions. Begin by dividing m by 2, and if it divides evenly, then m is not prime. Otherwise, divide by 3, then 4, then 5, etc. If at any point m is found to be divisible by a number d in the range 2 d m-1, then halt, and conclude that m is composite. Otherwise, conclude that m is prime. A moment’s thought shows that one need not do any trial divisions by numbers d which are themselves composite. For instance, if a trial division by 2 fails (i.e. has non-zero remainder, so m is odd), then a trial division by 4, 6, or 8, or any even number, must also fail. Thus to test a number m for primality, one need only do trial divisions by prime numbers less than m. Furthermore, it is not necessary to go all the way up to m-1. One need only do trial divisions of m by primes p in the range 2 p m . To see this, suppose m 1 is composite. Then there exist positive integers a and b such that 1 < a < m, 1 < b < m, and m = ab . But if both a m and b m , then ab m, contradicting that m = ab . Hence one of a or b must be less than or equal to m . To implement this process in java you will write a function called isPrime() with the following signature: static boolean isPrime(int m, int[] P) This function will return true or false according to whether m is prime or composite. The array argument P will contain a sufficient number of primes to do the testing. Specifically, at the time isPrime() is called, array P must contain (at least) all primes p in the range 2 p m . For instance, to test m = 53 for primality, one must do successive trial divisions by 2, 3, 5, and 7. We go no further since 11 53 . Thus a precondition for the function call isPrime(53, P) is that P[0] = 2 , P[1] = 3 , P[2] = 5, and P[3] = 7 . The return value in this case would be true since all these divisions fail. Similarly to test m =143 , one must do trial divisions by 2, 3, 5, 7, and 11 (since 13 143 ). The precondition for the function call isPrime(143, P) is therefore P[0] = 2 , P[1] = 3 , P[2] = 5, P[3] = 7 , and P[4] =11. The return value in this case would be false since 11 divides 143. Function isPrime() should contain a loop that steps through array P, doing trial divisions. This loop should terminate when 2 either a trial division succeeds, in which case false is returned, or until the next prime in P is greater than m , in which case true is returned. Function main() in this project will read the command line argument n, allocate an int array of length n, fill the array with primes, then print the contents of the array to stdout according to the format described below. In the context of function main(), we will refer to this array as Primes[]. Thus array Primes[] plays a dual role in this project. On the one hand, it is used to collect, store, and print the output data. On the other hand, it is passed to function isPrime() to test new integers for primality. Whenever isPrime() returns true, the newly discovered prime will be placed at the appropriate position in array Primes[]. This process works since, as explained above, the primes needed to test an integer m range only up to m , and all of these primes (and more) will already be stored in array Primes[] when m is tested. Of course it will be necessary to initialize Primes[0] = 2 manually, then proceed to test 3, 4, … for primality using function isPrime(). The following is an outline of the steps to be performed in function main(). • Check that the user supplied exactly one command line argument which can be interpreted as a positive integer n. If the command line argument is not a single positive integer, your program will print a usage message as specified in the examples below, then exit. • Allocate array Primes[] of length n and initialize Primes[0] = 2 . • Enter a loop which will discover subsequent primes and store them as Primes[1] , Primes[2], Primes[3] , ……, Primes[n -1] . This loop should contain an inner loop which walks through successive integers and tests them for primality by calling function isPrime() with appropriate arguments. • Print the contents of array Primes[] to stdout, 10 to a line separated by single spaces. In other words Primes[0] through Primes[9] will go on line 1, Primes[10] though Primes[19] will go on line 2, and so on. Note that if n is not a multiple of 10, then the last line of output will contain fewer than 10 primes. Your program, which will be called Prime.java, will produce output identical to that of the sample runs below. (As usual % signifies the unix prompt.) % java Prime Usage: java Prime [PositiveInteger] % java Prime xyz Usage: java Prime [PositiveInteger] % java Prime 10 20 Usage: java Prime [PositiveInteger] % java Prime 75 2 3 5 7 11 13 17 19 23 29 31 37 41 43 47 53 59 61 67 71 73 79 83 89 97 101 103 107 109 113 127 131 137 139 149 151 157 163 167 173 179 181 191 193 197 199 211 223 227 229 233 239 241 251 257 263 269 271 277 281 283 293 307 311 313 317 331 337 347 349 353 359 367 373 379 % 3 As you can see, inappropriate command line argument(s) generate a usage message which is similar to that of many unix commands. (Try doing the more command with no arguments to see such a message.) Your program will include a function called Usage() having signature static void Usage() that prints this message to stderr, then exits. Thus your program will contain three functions in all: main(), isPrime(), and Usage(). Each should be preceded by a comment block giving it’s name, a short description of it’s operation, and any necessary preconditions (such as those for isPrime().) See examples on the webpage.

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  • I need some help with either my SQL or my PHP I do not know which...

    - by sico87
    Hello I am creating a CMS and some of the functionality of it that the images that are within the content are managable. I currently trying to display a table that shows the the content title and then the associated images, ideally I would like a layout similar to this, Content Title Image 1 Image 2 Image 3 Content Title 2 Image 1 Image 2 Content Title 3 Image 1 The SQL the returns the data is actually formed using Codeigniters Active Record class, function getAllContentImages() { $this->db->select('*'); $this->db->from('contentImagesTable'); $this->db->join('contentTable', 'contentTable.contentId = contentImagesTable.contentId'); $this->db->join('categoryTable', 'categoryTable.categoryId = contentTable.categoryId'); $query = $this->db->get(); return $query->result_array(); } The array that is returned is looks like this, I have cut the size down for readability. Array ( [0] => Array ( [contentImageId] => 25 [contentImageName] => green.png [contentImageType] => .png [contentImagePath] => /var/www/bangmarketing.bang/media/uploads/contentImages/2/green.png [isHeadlineImage] => 1 [contentImageDateUploaded] => 1265222654 [contentId] => 2 [dashboardUserId] => 0 [contentTitle] => sadsadsadassss [contentAbstract] => <p>Pllllleeeeeeeaaaaasssssseeeeee Work</p> [contentBody] => <p>Please work :-( please</p> [contentOnline] => 0 [contentAllowComments] => 0 [contentDateCreated] => 1265124038 [categoryId] => 1 [categoryTitle] => blogsss [categoryAbstract] => <p>asdsdsadasdsadfdsgdgdsgdsgssssssssssss</p> [categorySlug] => blog [categoryIsSpecial] => 0 [categoryOnline] => 1 [categoryDateCreated] => 1266588327 ) [1] => Array ( [contentImageId] => 28 [contentImageName] => yellow.png [contentImageType] => .png [contentImagePath] => /var/www/bangmarketing.bang/media/uploads/contentImages/7/yellow.png [isHeadlineImage] => 1 [contentImageDateUploaded] => 1265388055 [contentId] => 7 [dashboardUserId] => 0 [contentTitle] => Another Blog [contentAbstract] => <p>This is another blog and it is shit becuase this does not work</p> [contentBody] => <p>ioasfihfududfhdufhuishdfiudshfiudhsfiuhdsiufhusdhfuids</p> [contentOnline] => 1 [contentAllowComments] => 0 [contentDateCreated] => 1265388034 [categoryId] => 1 [categoryTitle] => blogsss [categoryAbstract] => <p>asdsdsadasdsadfdsgdgdsgdsgssssssssssss</p> [categorySlug] => blog [categoryIsSpecial] => 0 [categoryOnline] => 1 [categoryDateCreated] => 1266588327 ) [2] => Array ( [contentImageId] => 33 [contentImageName] => portaski.jpg [contentImageType] => .jpg [contentImagePath] => /var/www/bangmarketing.bang/media/uploads/contentImages/11/portaski.jpg [isHeadlineImage] => 1 [contentImageDateUploaded] => 1265714175 [contentId] => 11 [dashboardUserId] => 0 [contentTitle] => Portaski - new product and brand launch by Bang [contentAbstract] => <p>Bang's experience in new product development has helped launch PortaSki &ndash; the pocket-sized device which is set to revolutionise skiing.</p> [contentBody] => <p>After developing Portaski's brand identity and positioning, Bang re-designed the product and its packaging ahead of launch in late 2008.</p> <p>A media and PR strategy was devised and implemented using Bang's close relationship with two of the UK's most influential organisations in the Advertising and Media Buying industries. On-line advertising was supported with editorial reviews in the UK's leading broadsheets and tabloids, which combined with pin-point HTML direct mail to drive consumers to the new e-commerce site.</p> <p>Impressive month-on-month growth has been achieved since launch, and the direct marketing activity resulted in an unprecedented 2.71% of targets going on-line to purchase a PortaSki.</p> <p>For further information visit <a href="http://www.portaski.com" target="_blank">www.portaski.com</a></p> [contentOnline] => 1 [contentAllowComments] => 0 [contentDateCreated] => 1265718184 [categoryId] => 1 [categoryTitle] => blogsss [categoryAbstract] => <p>asdsdsadasdsadfdsgdgdsgdsgssssssssssss</p> [categorySlug] => blog [categoryIsSpecial] => 0 [categoryOnline] => 1 [categoryDateCreated] => 1266588327 ) [3] => Array ( [contentImageId] => 26 [contentImageName] => housingplus.jpg [contentImageType] => .jpg [contentImagePath] => /var/www/bangmarketing.bang/media/uploads/contentImages/5/housingplus.jpg [isHeadlineImage] => 1 [contentImageDateUploaded] => 1265284989 [contentId] => 5 [dashboardUserId] => 0 [contentTitle] => Bang launches Housing Plus [contentAbstract] => <p>Bang has launched Housing Plus, the new brand for the Central Borders Housing Group, along with new sub-brands Property Care and SSHA.</p> [contentBody] => <p>The Midlands based Group, with turnover in excess of &pound;21M, appointed Bang in 2008 following an open pitch of over 40 agencies. Bang's work began with an extensive marketing research strategy that challenged the Group's former positioning and brand structure.</p> <p>The research unveiled that the housing sector demanded a values-led Group. This led Bang to develop the brave &lsquo;Together for the Right Reasons' positioning for Housing Plus.</p> <p>Chris Garratt, Marketing Director at Bang explained "The housing sector has witnessed wholesale change in recent years. Much to tenant's dismay, many associations and Groups appear to be losing touch with their roots, we wanted to develop a Group for associations who place principles at the heart of their corporate strategy".</p> <p>The repositioned sub-brands also play an important role in the Group's revised brand by highlighting Housing Plus' willingness to embrace and nurture individual identities. Chris Garratt continued "By adopting a &lsquo;house of brands' hierarchy from the outset, Housing Plus has sent out a strong message to prospective strategic partners".</p> <p>Bang handled all aspects of work for the redevelopment of the three brands, including research, brand creation, naming, positioning, internal branding and communications, advertising, the brand launches, building the brands' on-line presence and the creation of a powerful brand film &ndash; which is already attracting significant interest from across the sector.</p> [contentOnline] => 1 [contentAllowComments] => 0 [contentDateCreated] => 1265285940 [categoryId] => 8 [categoryTitle] => News [categoryAbstract] => <p>The world at Bang Marketing moves fast, keep up to date w [categorySlug] => news [categoryIsSpecial] => 0 [categoryOnline] => 1 [categoryDateCreated] => 1265283717 ) I need a way that I can get all the content images associated with the same content title in one group and then display under the content title. Can anyone help?

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