Search Results

Search found 11680 results on 468 pages for 'convenience methods'.

Page 353/468 | < Previous Page | 349 350 351 352 353 354 355 356 357 358 359 360  | Next Page >

• Forcing an item to remain in place in a jQuery UI Sortable list

  - by calumbrodie

  I've set up a jQuery sortable list but I need to be able to keep some items in the sortable 'fixed' in place and for the other items to sort around them. I thought that there would be built in methods to achieve this, alas this is not the case. I'm able to set up the list and not include the items in question: <ul id="fruit"> <li class="fixed">apples</li> <li>oranges</li> <li>bananas</li> <li>pineapples</li> <li>grapes</li> <li class="fixed">pears</li> <li>mango</li> </ul> <script type="text/javascript"> $('#fruit').sortable({items: "li:not('.fixed')"}) </script> This stops me from drag/dropping these items but they still move if the items around them are sorted. There may be a way to do this using the many callbacks that this method has but I've been unable to work this out. Maybe this method would be a good addition to the UI Sortable options?

  Read the article

• what's the alternative to readonlycollection when using lazy="extra"?

  - by Kunjan

  I am trying to use lazy="extra" for the child collection of Trades I have on my Client object. The trades is an Iset<Trade Trades, exposed as ReadOnlyCollection<Trade because I do not want anyone to modify the collection directly. As a result, I have added AddTrade and RemoveTrade methods. Now I have a Client Search page where I need to show the Trade Count. and on the Client details page I have a tab where I need to show all the trades for the Client in paged gridview. What I want to achieve is, for the search when I say on the client object as client.Trades.Count, nHibernate should only fire a select count(*) query. Hence I am using lazy="extra". But because I am using a ReadOnlyCollection, nHibernate fires a count query & a separate query to load the child collection trades completely. Also, I cannot include the Trades in my initial search request as this would disturb the paging because a counterparty can have n trades which would result in n rows, when I am searching clients only. So the child collections have to be loaded lazily. The second problem is that on the client details page -- Trades grid view, I have enabled paging for performance reasons. But by nature nHibernate loads the entire collection of trades as the user goes from one page to another. Ideally I want to control this by getting only trades specific to the page the user is on. How can I achieve this? I came across this very good article. http://stackoverflow.com/questions/876976/implementing-ipagedlistt-on-my-models-using-nhibernate But I am not sure if this will work for me, as lazy=extra currently doesnt work as expected with the ReadOnlyCollection. So, if I went ahead and implemented the solution this way and further enhanced it by making the List/Set Immutable, will lazy=extra give me the same problem as with ReadOnlyCollections?

  Read the article

• Settings variable values in a Moq Callback() call

  - by Adam Driscoll

  I think I may be a bit confused on the syntax of the Moq Callback methods. When I try to do something like this: IFilter filter = new Filter(); List<IFoo> objects = new List<IFoo> { new Foo(), new Foo() }; IQueryable myFilteredFoos = null; mockObject.Setup(m => m.GetByFilter(It.IsAny<IFilter>())).Callback( (IFilter filter) => myFilteredFoos = filter.FilterCollection(objects)).Returns(myFilteredFoos.Cast<IFooBar>()); This throws a exception because myFilteredFoos is null during the Cast<IFooBar>() call. Is this not working as I expect? I would think FilterCollection would be called and then myFilteredFoos would be non-null and allow for the cast. FilterCollection is not capable of returning a null which draws me to the conclusion it is not being called. Also, when I declare myFilteredFoos like this: Queryable myFilteredFoos; The Return call complains that myFilteredFoos may be used before it is initialized.

  Read the article

• Any way for a class to prevent outside code from declaring variables of its type?

  - by supercat

  Is it possible for a class of exposing a type for function returns, without allowing users of that class to create variables of that type? A couple usage scenarios: A Fluent interface on a large class; a statement like "foo=bar.WithX(5).WithY(9).WithZ(19);" would be inefficient if it had to create three new instances of the class, but could be much more efficient if the WithX could create one instance, and the other statements could simply use it. A class may wish to support a statement like "foo[19].x = 9;" even when foo itself isn't an array, and does not hold the data in class instances that can be exposed to the public; one way to do that is to have foo[19] return a struct which holds a reference to 'foo' and the value '19', and has a member property 'x' which could call "foo.SetXValue(19, 9);" Such a struct could have a conversion operator to convert itself to the "apparent" type of foo[19]. In both of these scenarios, storing the value returned by a method or property into a variable and then using it more than once would cause strange behavior. It would be desirable if the designer of the class exposing such methods or properties could ensure that callers wouldn't be able to use them more than once. Is there any practical way to accomplish that?

  Read the article

• DomainContext class is not created in a RIA services class library solution

  - by Konamiman

  I have created a RIA services class library project and things are not going as I expected. The problem is that when I add domain service classes to the server project, the corresponding domain context classes are not generated on the client project. I start by creating a new project of type WCF RIA services class library. The generated solution has two projects: RIAServicesLibrary1 (the Silverlight class library project) and RIAServicesLibrary1.Web (the class library that will hold the services). Then I add a new project item to RIAServicesLibrary1.Web of type DomainServiceClass. I add a sample method so that the resulting class code is: namespace RIAServicesLibrary1.Web { using System; using System.Collections.Generic; using System.ComponentModel; using System.ComponentModel.DataAnnotations; using System.Linq; using System.ServiceModel.DomainServices.Hosting; using System.ServiceModel.DomainServices.Server; // TODO: Create methods containing your application logic. [EnableClientAccess()] public class DomainService1 : DomainService { [Invoke] void DoSomething() { } } } Then I generate the whole solution and... nothing happens on the client project. The Generated_Code folder is empty, and the domain context object for the service is not here. Funny enough, if I add a new item of type Authentication domain service, it works as expected: the file RIAServicesLibrary1.Web.g.cs is created on the client project, containing the AuthenticationDomainService1 class as expected. So what's happening here? Am I doing something wrong? Note: I am using Visual Studio 2010 Ultimate RTM and WCF RIA services 1.0.

  Read the article

• Advice using leaks in instruments for noobs

  - by Gyozo Kudor

  Hello I am pretty new to iphone development. I have run my app for the first time using the "Leaks" from "Instruments". It shows me several leaks around 20 the smallest is 32 bytes and there is one with 1KB. I have followed the memory management guidelines, (i (think i) understand how and when to use release, not to use it when adding to autorelease pools, for every copy, retain, init there should be a release,... etc). I don't think I understand the output of the Leaks in instruments. What does "Responsible library" and "Responsible frame" mean. Because there are some classes and methods i never used directly. Are there any good tutorials for debugging memory leaks in instruments or other advice you can give me regarding leaks. Thanks in advance. Here are the largest 2 leaks. Leaked Object # Address Size Responsible Library Responsible Frame Malloc 1.00 KB 0x4827400 1024 CFNetwork std::vector *, std::allocator * ::reserve(unsigned long) // i have no idea what this is. Leaked Object # Address Size Responsible Library Responsible Frame Malloc 128 Bytes 5 640 UIKit UIImagePickerLoadPhotoLibraryIfNecessary // so this means UIImagePicker is leaking memory? The first leak i get Leaked Object # Address Size Responsible Library Responsible Frame Malloc 128 Bytes 0x442dfd0 128 UIKit UIKeyboardInputManagerClassForInputMode I don't understand any of those.

  Read the article

• Django: Complex filter parameters or...?

  - by minder

  This question is connected to my other question but I changed the logic a bit. I have models like this: from django.contrib.auth.models import Group class Category(models.Model): (...) editors = ForeignKey(Group) class Entry(models.Model): (...) category = ForeignKey(Category) Now let's say User logs into admin panel and wants to change an Entry. How do I limit the list of Entries only to those, he has the right to edit? I mean: How can I list only those Entries which are assigned to a Category that in its "editors" field has one of the groups the User belongs to? What if User belongs to several groups? I still need to show all relevant Entries. I tried experimenting with changelist_view() and queryset() methods but this problem is a bit too complex for me. I'm also wondering if granular-permissions could help me with the task, but for now I have no clue. I came up only with this: First I get the list of all Groups the User belongs to. Then for each Group I get all connected Categories and then for each Category I get all Entries that belong to these Categories. Unfortunately I have no idea how to stitch everything together as filter() parameters to produce a nice single QuerySet.

  Read the article

• When is LINQ (to objects) Overused?

  - by Mystagogue

  My career started as a hard-core functional-paradigm developer (LISP), and now I'm a hard-care .net/C# developer. Of course I'm enamored with LINQ. However, I also believe in (1) using the right tool for the job and (2) preserving the KISS principle: of the 60+ engineers I work with, perhaps only 20% have hours of LINQ / functional paradigm experience, and 5% have 6 to 12 months of such experience. In short, I feel compelled to stay away from LINQ unless I'm hampered in achieving a goal without it (wherein replacing 3 lines of O-O code with one line of LINQ is not a "goal"). But now one of the engineers, having 12 months LINQ / functional-paradigm experience, is using LINQ to objects, or at least lambda expressions anyway, in every conceivable location in production code. My various appeals to the KISS principle have not yielded any results. Therefore... What published studies can I next appeal to? What "coding standard" guideline have others concocted with some success? Are there published LINQ performance issues I could point out? In short, I'm trying to achieve my first goal - KISS - by indirect persuasion. Of course this problem could be extended to countless other areas (such as overuse of extension methods). Perhaps there is an "uber" guide, highly regarded (e.g. published studies, etc), that takes a broader swing at this. Anything?

  Read the article

• Finding perfect numbers in C# (optimization)

  - by paradox

  I coded up a program in C# to find perfect numbers within a certain range as part of a programming challenge . However, I realized it is very slow when calculating perfect numbers upwards of 10000. Are there any methods of optimization that exist for finding perfect numbers? My code is as follows: using System; using System.Collections.Generic; using System.Linq; namespace ConsoleTest { class Program { public static List<int> FindDivisors(int inputNo) { List<int> Divisors = new List<int>(); for (int i = 1; i<inputNo; i++) { if (inputNo%i==0) Divisors.Add(i); } return Divisors; } public static void Main(string[] args) { const int limit = 100000; List<int> PerfectNumbers = new List<int>(); List<int> Divisors=new List<int>(); for (int i=1; i<limit; i++) { Divisors = FindDivisors(i); if (i==Divisors.Sum()) PerfectNumbers.Add(i); } Console.Write("Output ="); for (int i=0; i<PerfectNumbers.Count; i++) { Console.Write(" {0} ",PerfectNumbers[i]); } Console.Write("\n\n\nPress any key to continue . . . "); Console.ReadKey(true); } } }

  Read the article

• ASP.NET MVC 4 async child action

  - by ShadowChaser

  I have an ASP.NET MVC 4 application targeting .NET 4.5. One of our child actions makes a call out to a web service using HttpClient. Since we're blocking on IO waiting for the HttpClient response, it makes a great deal of sense to convert the code to the async/await pattern. However, when MVC 4 attempts to execute the child action, we get the following error message: HttpServerUtility.Execute blocked while waiting for an asynchronous operation to complete. At first glance, it appears as though MVC 4 does not support async/await within a child action. The only remaining option is to run using synchronous code and force a "Wait" on the async task. As we all know, touching .Result or .Wait() on an async task in an ASP.NET context will cause an immediate deadlock. My async logic is wrapped in a class library, so I can't use the "await blah.ConfigureAwait(false)" trick. Remember, tagging "async" on the child action and using await causes an error, and that prevents me from configuring the await. I'm painted into a corner at this point. Is there any way to consume async methods in an MVC 4 child action? Seems like a flat out bug with no workarounds.

  Read the article

• iOS5: Confusion with loadview and init and instance variables

  - by user743550

  I'm new to iOS5 and storyboarding. I noticed that if I declare an instance variables inside my viewcontroller .h file and set the values inside my init of .m file of my viewcontroller, whe the view of the viewcontroller is displayed, my instance variables show null inside viewDidLoad. In order for me to get myvariables, I'd need to do [self init] inside viewDidLoad. My questions are: @interface tableViewController : UITableViewController { NSMutableArray *myvariable; } @end @implementation tableViewController -(id)init { myvariable = [[NSMutableArray alloc]initWithObjects:@"Hi2",@"Yo2",@"whatsup2", nil]; } - (void)viewDidLoad { NSLog(@"%@",myvariable); // DISPLAYS NULL [super viewDidLoad]; } Why isn't my variables available in viewdidLoad when I declared and implemented in my .h and .m files? If that's the case, is viewDidLoad or viewWillAppear the common places to load the data for the viewcontroller? It looks like even if you instantiate a viewcontroller, the init function gets called but the viewDidLoad doesn't necessarily have the variables to be displayed. Where's the right place/methods to load the model(data) for my viewcontroller? Thanks in advance

  Read the article

• Raytracing (LoS) on 3D hex-like tile maps

  - by herenvardo

  Greetings, I'm working on a game project that uses a 3D variant of hexagonal tile maps. Tiles are actually cubes, not hexes, but are laid out just like hexes (because a square can be turned to a cube to extrapolate from 2D to 3D, but there is no 3D version of a hex). Rather than a verbose description, here goes an example of a 4x4x4 map: (I have highlighted an arbitrary tile (green) and its adjacent tiles (yellow) to help describe how the whole thing is supposed to work; but the adjacency functions are not the issue, that's already solved.) I have a struct type to represent tiles, and maps are represented as a 3D array of tiles (wrapped in a Map class to add some utility methods, but that's not very relevant). Each tile is supposed to represent a perfectly cubic space, and they are all exactly the same size. Also, the offset between adjacent "rows" is exactly half the size of a tile. That's enough context; my question is: Given the coordinates of two points A and B, how can I generate a list of the tiles (or, rather, their coordinates) that a straight line between A and B would cross? That would later be used for a variety of purposes, such as determining Line-of-sight, charge path legality, and so on. BTW, this may be useful: my maps use the (0,0,0) as a reference position. The 'jagging' of the map can be defined as offsetting each tile ((y+z) mod 2) * tileSize/2.0 to the right from the position it'd have on a "sane" cartesian system. For the non-jagged rows, that yields 0; for rows where (y+z) mod 2 is 1, it yields 0.5 tiles. I'm working on C#4 targeting the .Net Framework 4.0; but I don't really need specific code, just the algorithm to solve the weird geometric/mathematical problem. I have been trying for several days to solve this at no avail; and trying to draw the whole thing on paper to "visualize" it didn't help either :( . Thanks in advance for any answer

  Read the article

• Perl XML SAX parser emulating XML::Simple record for record

  - by DVK

  Short Q summary: I am looking a fast XML parser (most likely a wrapper around some standard SAX parser) which will produce per-record data structure 100% identical to those produced by XML::Simple. Details: We have a large code infrastructure which depends on processing records one-by-one and expects the record to be a data structure in a format produced by XML::Simple since it always used XML::Simple since early Jurassic era. An example simple XML is: <root> <rec><f1>v1</f1><f2>v2</f2></rec> <rec><f1>v1b</f1><f2>v2b</f2></rec> <rec><f1>v1c</f1><f2>v2c</f2></rec> </root> And example rough code is: sub process_record { my ($obj, $record_hash) = @_; # do_stuff } my $records = XML::Simple->XMLin(@args)->{root}; foreach my $record (@$records) { $obj->process_record($record) }; As everyone knows XML::Simple is, well, simple. And more importantly, it is very slow and a memory hog - due to being a DOM parser and needing to build/store 100% of data in memory. So, it's not the best tool for parsing an XML file consisting of large amount of small records record-by-record. However, re-writing the entire code (which consist of large amount of "process_record"-like methods) to work with standard SAX parser seems like an big task not worth the resources, even at the cost of living with XML::Simple. What I'm looking for is an existing module which will probably be based on a SAX parser (or anything fast with small memory footprint) which can be used to produce $record hashrefs one by one based on the XML pictured above that can be passed to $obj->process_record($record) and be 100% identical to what XML::Simple's hashrefs would have been. I don't care much what the interface of the new module is - e.g whether I need to call next_record() or give it a callback coderef accepting a record.

  Read the article

• dynamically create class in scala, should I use interpreter?

  - by Phil

  Hi, I want to create a class at run-time in Scala. For now, just consider a simple case where I want to make the equivalent of a java bean with some attributes, I only know these attributes at run time. How can I create the scala class? I am willing to create from scala source file if there is a way to compile it and load it at run time, I may want to as I sometimes have some complex function I want to add to the class. How can I do it? I worry that the scala interpreter which I read about is sandboxing the interpreted code that it loads so that it won't be available to the general application hosting the interpreter? If this is the case, then I wouldn't be able to use the dynamically loaded scala class. Anyway, the question is, how can I dynamically create a scala class at run time and use it in my application, best case is to load it from a scala source file at run time, something like interpreterSource("file.scala") and its loaded into my current runtime, second best case is some creation by calling methods ie. createClass(...) to create it at runtime. Thanks, Phil

  Read the article

• Create System.Data.Linq.Table in Code for Testing

  - by S. DePouw

  I have an adapter class for Linq-to-Sql: public interface IAdapter : IDisposable { Table<Data.User> Activities { get; } } Data.User is an object defined by Linq-to-Sql pointing to the User table in persistence. The implementation for this is as follows: public class Adapter : IAdapter { private readonly SecretDataContext _context = new SecretDataContext(); public void Dispose() { _context.Dispose(); } public Table<Data.User> Users { get { return _context.Users; } } } This makes mocking the persistence layer easy in unit testing, as I can just return whatever collection of data I want for Users (Rhino.Mocks): Expect.Call(_adapter.Users).Return(users); The problem is that I cannot create the object 'users' since the constructors are not accessible and the class Table is sealed. One option I tried is to just make IAdapter return IEnumerable or IQueryable, but the problem there is that I then do not have access to the methods ITable provides (e.g. InsertOnSubmit()). Is there a way I can create the fake Table in the unit test scenario so that I may be a happy TDD developer?

  Read the article

• Could CouchDB benefit significantly from the use of BERT instead of JSON?

  - by Victor Rodrigues

  I appreciate a lot CouchDB attempt to use universal web formats in everything it does: RESTFUL HTTP methods in every interaction, JSON objects, javascript code to customize database and documents. CouchDB seems to scale pretty well, but the individual cost to make a request usually makes 'relational' people afraid of. Many small business applications should deal with only one machine and that's all. In this case the scalability talk doesn't say too much, we need more performance per request, or people will not use it. BERT (Binary ERlang Term http://bert-rpc.org/ ) has proven to be a faster and lighter format than JSON and it is native for Erlang, the language in which CouchDB is written. Could we benefit from that, using BERT documents instead of JSON ones? I'm not saying just for retrieving in views, but for everything CouchDB does, including syncing. And, as a consequence of it, use Erlang functions instead of javascript ones. This would modify some original CouchDB principles, because today it is very web oriented. Considering I imagine few people would make their database API public and usually its data is accessed by the users through an application, it would be a good deal to have the ability to configure CouchDB for working faster. HTTP+JSON calls could still be handled by CouchDB, considering an extra cost in these cases because of parsing.

  Read the article

• Can not call web service with basic authentication using WCF

  - by RexM

  I've been given a web service written in Java that I'm not able to make any changes to. It requires the user authenticate with basic authentication to access any of the methods. The suggested way to interact with this service in .NET is by using Visual Studio 2005 with WSE 3.0 installed. This is an issue, since the project is already using Visual Studio 2008 (targeting .NET 2.0). I could do it in VS2005, however I do not want to tie the project to VS2005 or do it by creating an assembly in VS2005 and including that in the VS2008 solution (which basically ties the project to 2005 anyway for any future changes to the assembly). I think that either of these options would make things complicated for new developers by forcing them to install WSE 3.0 and keep the project from being able to use 2008 and features in .NET 3.5 in the future... ie, I truly believe using WCF is the way to go. I've been looking into using WCF for this, however I'm unsure how to get the WCF service to understand that it needs to send the authentication headers along with each request. I'm getting 401 errors when I attempt to do anything with the web service. This is what my code looks like: WebHttpBinding webBinding = new WebHttpBinding(); ChannelFactory<MyService> factory = new ChannelFactory<MyService>(webBinding, new EndpointAddress( "http://127.0.0.1:80/Service/Service/")); factory.Endpoint.Behaviors.Add(new WebHttpBehavior()); factory.Credentials.UserName.UserName = "username"; factory.Credentials.UserName.Password = "password"; MyService proxy = factory.CreateChannel(); proxy.postSubmission(_postSubmission); This will run and throw the following exception: "The HTTP request is unauthorized with client authentication scheme 'Anonymous'. The authentication header received from the server was 'Basic realm=realm'." And this has an inner exception of: "The remote server returned an error: (401) Unauthorized." Any thoughts about what might be causing this issue would be greatly appreciated.

  Read the article

• How to use iPhone SDK Private APIs

  - by eagle

  I haven't found a comprehensive list of the steps that are required to use a private API from the iPhone Library. In particular, I would like to know how to get header files, if they are even required, how to get it to compile (when I simply add the header, it complains that the functions aren't defined), and what resources one can use to learn about private APIs (e.g. from other user's experiences, such as http://iphonedevwiki.net/ which has a few). I've read in other places that people recommend using class-dump to get the headers. Are there any alternative methods? I've noticed that there are some repositories of iPhone Private SDKs, what are the most up to date resources you would recommend? Most of the previous questions about documentation of private APIs, have all linked to Erica Sadun's website, which doesn't seem to have documentation anymore (all the links on the left are crossed out). Please save the comments about not using private API's... I know of the biggest risks: App will get rejected by Apple. App will break in future updates to the OS. I'm talking about legitimate uses, such as: Private application use (e.g. for unit testing, or messing around to see what's possible)

  Read the article

• How do I hook into the action method for an iPad popover toolbar button?

  - by Elisabeth

  Hi, I am using the split view template to create a simple split view that has, of course, a popover in Portrait mode. I'm using the default code generated by template that adds/removes the toolbar item and sets the popover controller and removes it. These two methods are splitViewController:willShowViewController:... and splitViewController:willHideViewController:... I'm trying to figure out how to make the popover disappear if the user taps on the toolbar button while the popover is displayed. You can make the popover disappear without selecting an item if you tap anywhere outside the popover, but I would also like to make it disappear if the user taps the button again. Where I'm stuck is this: there doesn't seem to be an obvious, easy way to hook into the action for the toolbar button. I can tell, using the debugger, that the action that's being called on the button is showMasterInPopover. And I am new to working with selectors programmatically, I admit. Can I somehow write an action and set it on the toolbar item without overriding the action that's already there? e.g. add an action that calls the one that's there now? Or would I have to write an action that shows/hides the popover myself (behavior that's being done behind the scenes presumably by the split view controller now???). Or am I missing an easy way to add this behavior to this button without changing the existing behavior that's being set up for me? Thank you!

  Read the article

• Consume webservice from a .NET DLL - app.config problem

  - by Asaf R

  Hi, I'm building a DLL, let's call it mydll.dll, and in it I sometimes need to call methods from webservice, myservice. mydll.dll is built using C# and .NET 3.5. To consume myservice from mydll I've Added A Service in Visual Studio 2008, which is more or less the same as using svcutil.exe. Doing so creates a class I can create, and adds endpoint and bindings configurations to mydll app.config. The problem here is that mydll app.config is never loaded. Instead, what's loaded is the app.config or web.config of the program I use mydll in. I expect mydll to evolve, which is why I've decoupled it's funcionality from the rest of my system to begin with. During that evolution it will likely add more webservice to which it'll call, ruling out manual copy-paste ways to overcome this problem. I've looked at several possible approaches to attacking this issue: Manually copy endpoints and bindings from mydell app.config to target EXE or web .config file. Couples the modules, not flexible Include endpoints and bindings from mydll app.config in target .config, using configSource (see here). Also add coupling between modules Programmatically load mydll app.config, read endpoints and bindings, and instantiate Binding and EndpointAddress. Use a different tool to create local frontend for myservice I'm not sure which way to go. Option 3 sounds promising, but as it turns out it's a lot of work and will probably introduce several bugs, so it doubtfully pays off. I'm also not familiar with any tool other than the canonical svcutil.exe. Please either give pros and cons for the above alternative, provide tips for implementing any of them, or suggest other approaches. Thanks, Asaf

  Read the article

• How should I handle persistence in a Java MUD? OptimisticLockException handling

  - by Chase

  I'm re-implementing a old BBS MUD game in Java with permission from the original developers. Currently I'm using Java EE 6 with EJB Session facades for the game logic and JPA for the persistence. A big reason I picked session beans is JTA. I'm more experienced with web apps in which if you get an OptimisticLockException you just catch it and tell the user their data is stale and they need to re-apply/re-submit. Responding with "try again" all the time in a multi-user game would make for a horrible experience. Given that I'd expect several people to be targeting a single monster during a fight I think the chance of an OptimisticLockException would be high. My view code, the part presenting a telnet CLI, is the EJB client. Should I be catching the PersistenceExceptions and TransactionRolledbackLocalExceptions and just retrying? How do you decide when to stop? Should I switch to pessimistic locking? Is persisting after every user command overkill? Should I be loading the entire world in RAM and dumping the state every couple of minutes? Do I make my session facade a EJB 3.1 singleton which would function as a choke point and therefore eliminating the need to do any type of JPA locking? EJB 3.1 singletons function as a multiple reader/single writer design (you annotate the methods as readers and writers). Basically, what is the best design and java persistence API for highly concurrent data changes in an application where it is not acceptable to present resubmit/retry prompts to the user?

  Read the article

• Implementation review for a MVC.NET app with custom membership

  - by mrjoltcola

  I'd like to hear if anyone sees any problems with how I implemented the security in this Oracle based MVC.NET app, either security issues, concurrency issues or scalability issues. First, I implemented a CustomOracleMembershipProvider to handle the database interface to the membership store. I implemented a custom Principal named User which implements IPrincipal, and it has a hashtable of Roles. I also created a separate class named AuthCache which has a simple cache for User objects. Its purpose is simple to avoid return trips to the database, while decoupling the caching from either the web layer or the data layer. (So I can share the cache between MVC.NET, WCF, etc.) The MVC.NET stock MembershipService uses the CustomOracleMembershipProvider (configured in web.config), and both MembershipService and FormsService share access to the singleton AuthCache. My AccountController.LogOn() method: 1) Validates the user via the MembershipService.Validate() method, also loads the roles into the User.Roles container and then caches the User in AuthCache. 2) Signs the user into the Web context via FormsService.SignIn() which accesses the AuthCache (not the database) to get the User, sets HttpContext.Current.User to the cached User Principal. In global.asax.cs, Application_AuthenticateRequest() is implemented. It decrypts the FormsAuthenticationTicket, accesses the AuthCache by the ticket.Name (Username) and sets the Principal by setting Context.User = user from the AuthCache. So in short, all these classes share the AuthCache, and I have, for thread synchronization, a lock() in the cache store method. No lock in the read method. The custom membership provider doesn't know about the cache, the MembershipService doesn't know about any HttpContext (so could be used outside of a web app), and the FormsService doesn't use any custom methods besides accessing the AuthCache to set the Context.User for the initial login, so it isn't dependent on a specific membership provider. The main thing I see now is that the AuthCache will be sharing a User object if a user logs in from multiple sessions. So I may have to change the key from just UserId to something else (maybe using something in the FormsAuthenticationTicket for the key?).

  Read the article

• PyQt and unittest - how to handle signals and slots

  - by Einar

  Hello, some small application I'm developing uses a module I have written to check certain web services via a REST API. I've been trying to add unit tests to it so I don't break stuff, and I stumbled upon a problem. I use a lot of signal-slot connections to perform operations asynchronously. For example a typical test would be (pseudo-Python), with postDataDownloaded as a signal: def testConnection(self): "Test connection and posts retrieved" def length_test(): self.assertEqual(len(self.client.post_data), 5) self.client.postDataReady.connect(length_test) self.client.get_post_list(limit=5) Now, unittest will report this test to be "ok" when running, regardless of the result (as another slot is being called), even if asserts fail (I will get an unhandled AssertionError). Example when deliberatiely making the test fail: Test connection and posts retrieved ... ok [... more tests...] OK Traceback (most recent call last): [...] AssertionError: 4 != 5 The slot inside the test is merely an experiment: I get the same results if it's outside (instance method). I also have to add that the various methods I'm calling all make HTTP requests, which means they take a bit of time (I need to mock the request - in the mean time I'm using SimpleHTTPServer to fake the connections and give them proper data). Is there a way around this problem?

  Read the article

• Static method , Abstract method , Interface method comparision ?

  - by programmerist

  When i choose these methods? i can not decide which one i must prefer or when will i use one of them?which one give best performance? First Type Usage public abstract class _AccessorForSQL { public virtual bool Save(string sp, ListDictionary ld, CommandType cmdType); public virtual bool Update(); public virtual bool Delete(); public virtual DataSet Select(); } class GenAccessor : _AccessorForSQL { DataSet ds; DataTable dt; public override bool Save(string sp, ListDictionary ld, CommandType cmdType) { } public override bool Update() { return true; } public override bool Delete() { return true; } public override DataSet Select() { DataSet dst = new DataSet(); return dst; } Second Type Usage Also i can write it below codes: public class GenAccessor { public Static bool Save() { } public Static bool Update() { } public Static bool Delete() { } } Third Type Usage Also i can write it below codes: public interface IAccessorForSQL { bool Delete(); bool Save(string sp, ListDictionary ld, CommandType cmdType); DataSet Select(); bool Update(); } public class _AccessorForSQL : IAccessorForSQL { private DataSet ds; private DataTable dt; public virtual bool Save(string sp, ListDictionary ld, CommandType cmdType) { } } } I can use first one below usage: GenAccessor gen = New GenAccessor(); gen.Save(); I can use second one below usage: GenAccessor.Save(); Which one do you prefer? When will i use them? which time i need override method ? which time i need static method?

  Read the article

• Hidden div height (changing my advice)

  - by fudgey

  Ok, I was going to answer someone's question here on SO about why their script wasn't working. They loaded content into a hidden div, then got the height so they could animate the wrapping div. But I always try to test the code I provide. So I made this demo to prove it to them. So, umm, have I entered the twilight zone or am I dreaming right now? pinches self OUCH! I tried that demo in Firefox, IE and Chrome and both methods return the same value. Firebug says zero! I rebooted my computer and I even changed the code a bit (removed the height function) and tried it with jQuery 1.3.2 and it still worked! I know hidden elements USED to return a zero value. Even this SO Answer is giving the advice I would have! So I guess my question is... did I miss something or are we giving bad advice?

  Read the article

< Previous Page | 349 350 351 352 353 354 355 356 357 358 359 360  | Next Page >