Search Results

Search found 18854 results on 755 pages for 'mr null'.

Page 85/755 | < Previous Page | 81 82 83 84 85 86 87 88 89 90 91 92  | Next Page >

• OWB 11gR2 - Early Arriving Facts

  - by Dawei Sun

  A common challenge when building ETL components for a data warehouse is how to handle early arriving facts. OWB 11gR2 introduced a new feature to address this for dimensional objects entitled Orphan Management. An orphan record is one that does not have a corresponding existing parent record. Orphan management automates the process of handling source rows that do not meet the requirements necessary to form a valid dimension or cube record. In this article, a simple example will be provided to show you how to use Orphan Management in OWB. We first import a sample MDL file that contains all the objects we need. Then we take some time to examine all the objects. After that, we prepare the source data, deploy the target table and dimension/cube loading map. Finally, we run the loading maps, and check the data in target dimension/cube tables. OK, let’s start… 1. Import MDL file and examine sample project First, download zip file from here, which includes a MDL file and three source data files. Then we open OWB design center, import orphan_management.mdl by using the menu File->Import->Warehouse Builder Metadata. Now we have several objects in BI_DEMO project as below: Mapping LOAD_CHANNELS_OM: The mapping for dimension loading. Mapping LOAD_SALES_OM: The mapping for cube loading. Dimension CHANNELS_OM: The dimension that contains channels data. Cube SALES_OM: The cube that contains sales data. Table CHANNELS_OM: The star implementation table of dimension CHANNELS_OM. Table SALES_OM: The star implementation table of cube SALES_OM. Table SRC_CHANNELS: The source table of channels data, that will be loaded into dimension CHANNELS_OM. Table SRC_ORDERS and SRC_ORDER_ITEMS: The source tables of sales data that will be loaded into cube SALES_OM. Sequence CLASS_OM_DIM_SEQ: The sequence used for loading dimension CHANNELS_OM. Dimension CHANNELS_OM This dimension has a hierarchy with three levels: TOTAL, CLASS and CHANNEL. Each level has three attributes: ID (surrogate key), NAME and SOURCE_ID (business key). It has a standard star implementation. The orphan management policy and the default parent setting are shown in the following screenshots: The orphan management policy options that you can set for loading are: Reject Orphan: The record is not inserted. Default Parent: You can specify a default parent record. This default record is used as the parent record for any record that does not have an existing parent record. If the default parent record does not exist, Warehouse Builder creates the default parent record. You specify the attribute values of the default parent record at the time of defining the dimensional object. If any ancestor of the default parent does not exist, Warehouse Builder also creates this record. No Maintenance: This is the default behavior. Warehouse Builder does not actively detect, reject, or fix orphan records. While removing data from a dimension, you can select one of the following orphan management policies: Reject Removal: Warehouse Builder does not allow you to delete the record if it has existing child records. No Maintenance: This is the default behavior. Warehouse Builder does not actively detect, reject, or fix orphan records. (More details are at http://download.oracle.com/docs/cd/E11882_01/owb.112/e10935/dim_objects.htm#insertedID1) Cube SALES_OM This cube is references to dimension CHANNELS_OM. It has three measures: AMOUNT, QUANTITY and COST. The orphan management policy setting are shown as following screenshot: The orphan management policy options that you can set for loading are: No Maintenance: Warehouse Builder does not actively detect, reject, or fix orphan rows. Default Dimension Record: Warehouse Builder assigns a default dimension record for any row that has an invalid or null dimension key value. Use the Settings button to define the default parent row. Reject Orphan: Warehouse Builder does not insert the row if it does not have an existing dimension record. (More details are at http://download.oracle.com/docs/cd/E11882_01/owb.112/e10935/dim_objects.htm#BABEACDG) Mapping LOAD_CHANNELS_OM This mapping loads source data from table SRC_CHANNELS to dimension CHANNELS_OM. The operator CHANNELS_IN is bound to table SRC_CHANNELS; CHANNELS_OUT is bound to dimension CHANNELS_OM. The TOTALS operator is used for generating a constant value for the top level in the dimension. The CLASS_FILTER operator is used to filter out the “invalid” class name, so then we can see what will happen when those channel records with an “invalid” parent are loading into dimension. Some properties of the dimension operator in this mapping are important to orphan management. See the screenshot below: Create Default Level Records: If YES, then default level records will be created. This property must be set to YES for dimensions and cubes if one of their orphan management policies is “Default Parent” or “Default Dimension Record”. This property is set to NO by default, so the user may need to set this to YES manually. LOAD policy for INVALID keys/ LOAD policy for NULL keys: These two properties have the same meaning as in the dimension editor. The values are set to the same as the dimension value when user drops the dimension into the mapping. The user does not need to modify these properties. Record Error Rows: If YES, error rows will be inserted into error table when loading the dimension. REMOVE Orphan Policy: This property is used when removing data from a dimension. Since the dimension loading type is set to LOAD in this example, this property is disabled. Mapping LOAD_SALES_OM This mapping loads source data from table SRC_ORDERS and SRC_ORDER_ITEMS to cube SALES_OM. This mapping seems a little bit complicated, but operators in the red rectangle are used to filter out and generate the records with “invalid” or “null” dimension keys. Some properties of the cube operator in a mapping are important to orphan management. See the screenshot below: Enable Source Aggregation: Should be checked in this example. If the default dimension record orphan policy is set for the cube operator, then it is recommended that source aggregation also be enabled. Otherwise, the orphan management processing may produce multiple fact rows with the same default dimension references, which will cause an “unstable rowset” execution error in the database, since the dimension refs are used as update match attributes for updating the fact table. LOAD policy for INVALID keys/ LOAD policy for NULL keys: These two properties have the same meaning as in the cube editor. The values are set to the same as in the cube editor when the user drops the cube into the mapping. The user does not need to modify these properties. Record Error Rows: If YES, error rows will be inserted into error table when loading the cube. 2. Deploy objects and mappings We now can deploy the objects. First, make sure location SALES_WH_LOCAL has been correctly configured. Then open Control Center Manager by using the menu Tools->Control Center Manager. Expand BI_DEMO->SALES_WH_LOCAL, click SALES_WH node on the project tree. We can see the following objects: Deploy all the objects in the following order: Sequence CLASS_OM_DIM_SEQ Table CHANNELS_OM, SALES_OM, SRC_CHANNELS, SRC_ORDERS, SRC_ORDER_ITEMS Dimension CHANNELS_OM Cube SALES_OM Mapping LOAD_CHANNELS_OM, LOAD_SALES_OM Note that we deployed source tables as well. Normally, we import source table from database instead of deploying them to target schema. However, in this example, we designed the source tables in OWB and deployed them to database for the purpose of this demonstration. 3. Prepare and examine source data Before running the mappings, we need to populate and examine the source data first. Run SRC_CHANNELS.sql, SRC_ORDERS.sql and SRC_ORDER_ITEMS.sql as target user. Then we check the data in these three tables. Table SRC_CHANNELS SQL> select rownum, id, class, name from src_channels; Records 1~5 are correct; they should be loaded into dimension without error. Records 6,7 and 8 have null parents; they should be loaded into dimension with a default parent value, and should be inserted into error table at the same time. Records 9, 10 and 11 have “invalid” parents; they should be rejected by dimension, and inserted into error table. Table SRC_ORDERS and SRC_ORDER_ITEMS SQL> select rownum, a.id, a.channel, b.amount, b.quantity, b.cost from src_orders a, src_order_items b where a.id = b.order_id; Record 178 has null dimension reference; it should be loaded into cube with a default dimension reference, and should be inserted into error table at the same time. Record 179 has “invalid” dimension reference; it should be rejected by cube, and inserted into error table. Other records should be aggregated and loaded into cube correctly. 4. Run the mappings and examine the target data In the Control Center Manager, expand BI_DEMO-> SALES_WH_LOCAL-> SALES_WH-> Mappings, right click on LOAD_CHANNELS_OM node, click Start. Use the same way to run mapping LOAD_SALES_OM. When they successfully finished, we can check the data in target tables. Table CHANNELS_OM SQL> select rownum, total_id, total_name, total_source_id, class_id,class_name, class_source_id, channel_id, channel_name,channel_source_id from channels_om order by abs(dimension_key); Records 1,2 and 3 are the default dimension records for the three levels. Records 8, 10 and 15 are the loaded records that originally have null parents. We see their parents name (class_name) is set to DEF_CLASS_NAME. Those records whose CHANNEL_NAME are Special_4, Special_5 and Special_6 are not loaded to this table because of the invalid parent. Error Table CHANNELS_OM_ERR SQL> select rownum, class_source_id, channel_id, channel_name,channel_source_id, err$$$_error_reason from channels_om_err order by channel_name; We can see all the record with null parent or invalid parent are inserted into this error table. Error reason is “Default parent used for record” for the first three records, and “No parent found for record” for the last three. Table SALES_OM SQL> select a.*, b.channel_name from sales_om a, channels_om b where a.channels=b.channel_id; We can see the order record with null channel_name has been loaded into target table with a default channel_name. The one with “invalid” channel_name are not loaded. Error Table SALES_OM_ERR SQL> select a.amount, a.cost, a.quantity, a.channels, b.channel_name, a.err$$$_error_reason from sales_om_err a, channels_om b where a.channels=b.channel_id(+); We can see the order records with null or invalid channel_name are inserted into error table. If the dimension reference column is null, the error reason is “Default dimension record used for fact”. If it is invalid, the error reason is “Dimension record not found for fact”. Summary In summary, this article illustrated the Orphan Management feature in OWB 11gR2. Automated orphan management policies improve ETL developer and administrator productivity by addressing an important cause of cube and dimension load failures, without requiring developers to explicitly build logic to handle these orphan rows.

  Read the article

• Enabling Service Availability in WCF Services

  - by cibrax

  It is very important for the enterprise to know which services are operational at any given point. There are many factors that can affect the availability of the services, some of them are external like a database not responding or any dependant service not working. However, in some cases, you only want to know whether a service is up or down, so a simple heart-beat mechanism with “Ping” messages would do the trick. Unfortunately, WCF does not provide a built-in mechanism to support this functionality, and you probably don’t to implement a “Ping” operation in any service that you have out there. For solving this in a generic way, there is a WCF extensibility point that comes to help us, the “Operation Invokers”. In a nutshell, an operation invoker is the class responsible invoking the service method with a set of parameters and generate the output parameters with the return value. What I am going to do here is to implement a custom operation invoker that intercepts any call to the service, and detects whether a “Ping” header was attached to the message. If the “Ping” header is detected, the operation invoker returns a new header to tell the client that the service is alive, and the real operation execution is omitted. In that way, we have a simple heart beat mechanism based on the messages that include a "Ping” header, so the client application can determine at any point whether the service is up or down. My operation invoker wraps the default implementation attached by default to any operation by WCF. internal class PingOperationInvoker : IOperationInvoker { IOperationInvoker innerInvoker; object[] outputs = null; object returnValue = null; public const string PingHeaderName = "Ping"; public const string PingHeaderNamespace = "http://tellago.serviceModel"; public PingOperationInvoker(IOperationInvoker innerInvoker, OperationDescription description) { this.innerInvoker = innerInvoker; outputs = description.SyncMethod.GetParameters() .Where(p => p.IsOut) .Select(p => DefaultForType(p.ParameterType)).ToArray(); var returnValue = DefaultForType(description.SyncMethod.ReturnType); } private static object DefaultForType(Type targetType) { return targetType.IsValueType ? Activator.CreateInstance(targetType) : null; } public object Invoke(object instance, object[] inputs, out object[] outputs) { object returnValue; if (Invoke(out returnValue, out outputs)) { return returnValue; } else { return this.innerInvoker.Invoke(instance, inputs, out outputs); } } private bool Invoke(out object returnValue, out object[] outputs) { object untypedProperty = null; if (OperationContext.Current .IncomingMessageProperties.TryGetValue(HttpRequestMessageProperty.Name, out untypedProperty)) { var httpRequestProperty = untypedProperty as HttpRequestMessageProperty; if (httpRequestProperty != null) { if (httpRequestProperty.Headers[PingHeaderName] != null) { outputs = this.outputs; if (OperationContext.Current .IncomingMessageProperties.TryGetValue(HttpRequestMessageProperty.Name, out untypedProperty)) { var httpResponseProperty = untypedProperty as HttpResponseMessageProperty; httpResponseProperty.Headers.Add(PingHeaderName, "Ok"); } returnValue = this.returnValue; return true; } } } var headers = OperationContext.Current.IncomingMessageHeaders; if (headers.FindHeader(PingHeaderName, PingHeaderNamespace) > -1) { outputs = this.outputs; MessageHeader<string> header = new MessageHeader<string>("Ok"); var untyped = header.GetUntypedHeader(PingHeaderName, PingHeaderNamespace); OperationContext.Current.OutgoingMessageHeaders.Add(untyped); returnValue = this.returnValue; return true; } returnValue = null; outputs = null; return false; } } The implementation above looks for the “Ping” header either in the Http Request or the Soap message. The next step is to implement a behavior for attaching this operation invoker to the services we want to monitor. [AttributeUsage(AttributeTargets.Method | AttributeTargets.Class, AllowMultiple = false, Inherited = true)] public class PingBehavior : Attribute, IServiceBehavior, IOperationBehavior { public void AddBindingParameters(ServiceDescription serviceDescription, ServiceHostBase serviceHostBase, Collection<ServiceEndpoint> endpoints, BindingParameterCollection bindingParameters) { } public void ApplyDispatchBehavior(ServiceDescription serviceDescription, ServiceHostBase serviceHostBase) { } public void Validate(ServiceDescription serviceDescription, ServiceHostBase serviceHostBase) { foreach (var endpoint in serviceDescription.Endpoints) { foreach (var operation in endpoint.Contract.Operations) { if (operation.Behaviors.Find<PingBehavior>() == null) operation.Behaviors.Add(this); } } } public void AddBindingParameters(OperationDescription operationDescription, BindingParameterCollection bindingParameters) { } public void ApplyClientBehavior(OperationDescription operationDescription, ClientOperation clientOperation) { } public void ApplyDispatchBehavior(OperationDescription operationDescription, DispatchOperation dispatchOperation) { dispatchOperation.Invoker = new PingOperationInvoker(dispatchOperation.Invoker, operationDescription); } public void Validate(OperationDescription operationDescription) { } } As an operation invoker can only be added in an “operation behavior”, a trick I learned in the past is that you can implement a service behavior as well and use the “Validate” method to inject it in all the operations, so the final configuration is much easier and cleaner. You only need to decorate the service with a simple attribute to enable the “Ping” functionality. [PingBehavior] public class HelloWorldService : IHelloWorld { public string Hello(string name) { return "Hello " + name; } } On the other hand, the client application needs to send a dummy message with a “Ping” header to detect whether the service is available or not. In order to simplify this task, I created a extension method in the WCF client channel to do this work. public static class ClientChannelExtensions { const string PingNamespace = "http://tellago.serviceModel"; const string PingName = "Ping"; public static bool IsAvailable<TChannel>(this IClientChannel channel, Action<TChannel> operation) { try { using (OperationContextScope scope = new OperationContextScope(channel)) { MessageHeader<string> header = new MessageHeader<string>(PingName); var untyped = header.GetUntypedHeader(PingName, PingNamespace); OperationContext.Current.OutgoingMessageHeaders.Add(untyped); try { operation((TChannel)channel); var headers = OperationContext.Current.IncomingMessageHeaders; if (headers.Any(h => h.Name == PingName && h.Namespace == PingNamespace)) { return true; } else { return false; } } catch (CommunicationException) { return false; } } } catch (Exception) { return false; } } } This extension method basically adds a “Ping” header to the request message, executes the operation passed as argument (Action<TChannel> operation), and looks for the corresponding “Ping” header in the response to see the results. The client application can use this extension with a single line of code, var client = new ServiceReference.HelloWorldClient(); var isAvailable = client.InnerChannel.IsAvailable<IHelloWorld>((c) => c.Hello(null)); The “isAvailable” variable will tell the client application whether the service is available or not. You can download the complete implementation from this location.    

  Read the article

• A DirectoryCatalog class for Silverlight MEF (Managed Extensibility Framework)

  - by Dixin

  In the MEF (Managed Extension Framework) for .NET, there are useful ComposablePartCatalog implementations in System.ComponentModel.Composition.dll, like: System.ComponentModel.Composition.Hosting.AggregateCatalog System.ComponentModel.Composition.Hosting.AssemblyCatalog System.ComponentModel.Composition.Hosting.DirectoryCatalog System.ComponentModel.Composition.Hosting.TypeCatalog While in Silverlight, there is a extra System.ComponentModel.Composition.Hosting.DeploymentCatalog. As a wrapper of AssemblyCatalog, it can load all assemblies in a XAP file in the web server side. Unfortunately, in silverlight there is no DirectoryCatalog to load a folder. Background There are scenarios that Silverlight application may need to load all XAP files in a folder in the web server side, for example: If the Silverlight application is extensible and supports plug-ins, there would be a /ClinetBin/Plugins/ folder in the web server, and each pluin would be an individual XAP file in the folder. In this scenario, after the application is loaded and started up, it would like to load all XAP files in /ClinetBin/Plugins/ folder. If the aplication supports themes, there would be a /ClinetBin/Themes/ folder, and each theme would be an individual XAP file too. The application would qalso need to load all XAP files in /ClinetBin/Themes/. It is useful if we have a DirectoryCatalog: DirectoryCatalog catalog = new DirectoryCatalog("/Plugins"); catalog.DownloadCompleted += (sender, e) => { }; catalog.DownloadAsync(); Obviously, the implementation of DirectoryCatalog is easy. It is just a collection of DeploymentCatalog class. Retrieve file list from a directory Of course, to retrieve file list from a web folder, the folder’s “Directory Browsing” feature must be enabled: So when the folder is requested, it responses a list of its files and folders: This is nothing but a simple HTML page: <html> <head> <title>localhost - /Folder/</title> </head> <body> <h1>localhost - /Folder/</h1> <hr> <pre> <a href="/">[To Parent Directory]</a><br> <br> 1/3/2011 7:22 PM 185 <a href="/Folder/File.txt">File.txt</a><br> 1/3/2011 7:22 PM &lt;dir&gt; <a href="/Folder/Folder/">Folder</a><br> </pre> <hr> </body> </html> For the ASP.NET Deployment Server of Visual Studio, directory browsing is enabled by default: The HTML <Body> is almost the same: <body bgcolor="white"> <h2><i>Directory Listing -- /ClientBin/</i></h2> <hr width="100%" size="1" color="silver"> <pre> <a href="/">[To Parent Directory]</a> Thursday, January 27, 2011 11:51 PM 282,538 <a href="Test.xap">Test.xap</a> Tuesday, January 04, 2011 02:06 AM &lt;dir&gt; <a href="TestFolder/">TestFolder</a> </pre> <hr width="100%" size="1" color="silver"> <b>Version Information:</b>&nbsp;ASP.NET Development Server 10.0.0.0 </body> The only difference is, IIS’s links start with slash, but here the links do not. Here one way to get the file list is read the href attributes of the links: [Pure] private IEnumerable<Uri> GetFilesFromDirectory(string html) { Contract.Requires(html != null); Contract.Ensures(Contract.Result<IEnumerable<Uri>>() != null); return new Regex( "<a href=\"(?<uriRelative>[^\"]*)\">[^<]*</a>", RegexOptions.IgnoreCase | RegexOptions.CultureInvariant) .Matches(html) .OfType<Match>() .Where(match => match.Success) .Select(match => match.Groups["uriRelative"].Value) .Where(uriRelative => uriRelative.EndsWith(".xap", StringComparison.Ordinal)) .Select(uriRelative => { Uri baseUri = this.Uri.IsAbsoluteUri ? this.Uri : new Uri(Application.Current.Host.Source, this.Uri); uriRelative = uriRelative.StartsWith("/", StringComparison.Ordinal) ? uriRelative : (baseUri.LocalPath.EndsWith("/", StringComparison.Ordinal) ? baseUri.LocalPath + uriRelative : baseUri.LocalPath + "/" + uriRelative); return new Uri(baseUri, uriRelative); }); } Please notice the folders’ links end with a slash. They are filtered by the second Where() query. The above method can find files’ URIs from the specified IIS folder, or ASP.NET Deployment Server folder while debugging. To support other formats of file list, a constructor is needed to pass into a customized method: /// <summary> /// Initializes a new instance of the <see cref="T:System.ComponentModel.Composition.Hosting.DirectoryCatalog" /> class with <see cref="T:System.ComponentModel.Composition.Primitives.ComposablePartDefinition" /> objects based on all the XAP files in the specified directory URI. /// </summary> /// <param name="uri"> /// URI to the directory to scan for XAPs to add to the catalog. /// The URI must be absolute, or relative to <see cref="P:System.Windows.Interop.SilverlightHost.Source" />. /// </param> /// <param name="getFilesFromDirectory"> /// The method to find files' URIs in the specified directory. /// </param> public DirectoryCatalog(Uri uri, Func<string, IEnumerable<Uri>> getFilesFromDirectory) { Contract.Requires(uri != null); this._uri = uri; this._getFilesFromDirectory = getFilesFromDirectory ?? this.GetFilesFromDirectory; this._webClient = new Lazy<WebClient>(() => new WebClient()); // Initializes other members. } When the getFilesFromDirectory parameter is null, the above GetFilesFromDirectory() method will be used as default. Download the directory’s XAP file list Now a public method can be created to start the downloading: /// <summary> /// Begins downloading the XAP files in the directory. /// </summary> public void DownloadAsync() { this.ThrowIfDisposed(); if (Interlocked.CompareExchange(ref this._state, State.DownloadStarted, State.Created) == 0) { this._webClient.Value.OpenReadCompleted += this.HandleOpenReadCompleted; this._webClient.Value.OpenReadAsync(this.Uri, this); } else { this.MutateStateOrThrow(State.DownloadCompleted, State.Initialized); this.OnDownloadCompleted(new AsyncCompletedEventArgs(null, false, this)); } } Here the HandleOpenReadCompleted() method is invoked when the file list HTML is downloaded. Download all XAP files After retrieving all files’ URIs, the next thing becomes even easier. HandleOpenReadCompleted() just uses built in DeploymentCatalog to download the XAPs, and aggregate them into one AggregateCatalog: private void HandleOpenReadCompleted(object sender, OpenReadCompletedEventArgs e) { Exception error = e.Error; bool cancelled = e.Cancelled; if (Interlocked.CompareExchange(ref this._state, State.DownloadCompleted, State.DownloadStarted) != State.DownloadStarted) { cancelled = true; } if (error == null && !cancelled) { try { using (StreamReader reader = new StreamReader(e.Result)) { string html = reader.ReadToEnd(); IEnumerable<Uri> uris = this._getFilesFromDirectory(html); Contract.Assume(uris != null); IEnumerable<DeploymentCatalog> deploymentCatalogs = uris.Select(uri => new DeploymentCatalog(uri)); deploymentCatalogs.ForEach( deploymentCatalog => { this._aggregateCatalog.Catalogs.Add(deploymentCatalog); deploymentCatalog.DownloadCompleted += this.HandleDownloadCompleted; }); deploymentCatalogs.ForEach(deploymentCatalog => deploymentCatalog.DownloadAsync()); } } catch (Exception exception) { error = new InvalidOperationException(Resources.InvalidOperationException_ErrorReadingDirectory, exception); } } // Exception handling. } In HandleDownloadCompleted(), if all XAPs are downloaded without exception, OnDownloadCompleted() callback method will be invoked. private void HandleDownloadCompleted(object sender, AsyncCompletedEventArgs e) { if (Interlocked.Increment(ref this._downloaded) == this._aggregateCatalog.Catalogs.Count) { this.OnDownloadCompleted(e); } } Exception handling Whether this DirectoryCatelog can work only if the directory browsing feature is enabled. It is important to inform caller when directory cannot be browsed for XAP downloading. private void HandleOpenReadCompleted(object sender, OpenReadCompletedEventArgs e) { Exception error = e.Error; bool cancelled = e.Cancelled; if (Interlocked.CompareExchange(ref this._state, State.DownloadCompleted, State.DownloadStarted) != State.DownloadStarted) { cancelled = true; } if (error == null && !cancelled) { try { // No exception thrown when browsing directory. Downloads the listed XAPs. } catch (Exception exception) { error = new InvalidOperationException(Resources.InvalidOperationException_ErrorReadingDirectory, exception); } } WebException webException = error as WebException; if (webException != null) { HttpWebResponse webResponse = webException.Response as HttpWebResponse; if (webResponse != null) { // Internally, WebClient uses WebRequest.Create() to create the WebRequest object. Here does the same thing. WebRequest request = WebRequest.Create(Application.Current.Host.Source); Contract.Assume(request != null); if (request.CreatorInstance == WebRequestCreator.ClientHttp && // Silverlight is in client HTTP handling, all HTTP status codes are supported. webResponse.StatusCode == HttpStatusCode.Forbidden) { // When directory browsing is disabled, the HTTP status code is 403 (forbidden). error = new InvalidOperationException( Resources.InvalidOperationException_ErrorListingDirectory_ClientHttp, webException); } else if (request.CreatorInstance == WebRequestCreator.BrowserHttp && // Silverlight is in browser HTTP handling, only 200 and 404 are supported. webResponse.StatusCode == HttpStatusCode.NotFound) { // When directory browsing is disabled, the HTTP status code is 404 (not found). error = new InvalidOperationException( Resources.InvalidOperationException_ErrorListingDirectory_BrowserHttp, webException); } } } this.OnDownloadCompleted(new AsyncCompletedEventArgs(error, cancelled, this)); } Please notice Silverlight 3+ application can work either in client HTTP handling, or browser HTTP handling. One difference is: In browser HTTP handling, only HTTP status code 200 (OK) and 404 (not OK, including 500, 403, etc.) are supported In client HTTP handling, all HTTP status code are supported So in above code, exceptions in 2 modes are handled differently. Conclusion Here is the whole DirectoryCatelog’s looking: Please click here to download the source code, a simple unit test is included. This is a rough implementation. And, for convenience, some design and coding are just following the built in AggregateCatalog class and Deployment class. Please feel free to modify the code, and please kindly tell me if any issue is found.

  Read the article

• Open source engagement as a professional reference

  - by Martin

  if one commits his or her time to an open source project, he or she may be invest a substantial amount of time without getting paid. As much as altruism is appreciable, I wonder whether it "counts" as an activity which can be shown and is valued in job applications. If the company is worth your time and working power, which it should be in my honest opinion. So I wonder whether there is something like a common practice in open source projects for this matters. Say, something like Mr. Martin has been working on our project for five years and has contributed this and that,[...] I we wish him very best for his future. Mr. ChiefofProject I think this is a just concern. Do have experiences you can share?

  Read the article

• unexpected EOF and end of document

  - by WASasquatch

  I have been fiddling with this code for a few days. Mind you I am a beginner. I just want to get my script to be able to download a remote file, and scan MineCraft plugins. I got the scan plugins to work, but I'm having two other issues. One, I can't get the mc_addplugin to work correctly, and I get a Unexpected EOF and unexpected end of document when running any other command besides mc_scanplugins or mc_start bash: -c: line 0: unexpected EOF while looking for matching `"' bash: -c: line 1: syntax error: unexpected end of file Help would be so much appreciated! Thanks in advance. #!/bin/bash # /etc/init.d/craftbukkit # version 0.9.1 2012-07-06 (YYYY-MM-DD) ### BEGIN INIT INFO # Provides: craftbukkit # Required-Start: $local_fs $remote_fs # Required-Stop: $local_fs $remote_fs # Should-Start: $network # Should-Stop: $network # Default-Start: 2 3 4 5 # Default-Stop: 0 1 6 # Short-Description: Starts craftbukkit server # Description: Starts and controls the craftbukkit server ### END INIT INFO # SETTINGS SERVICE='craftbukkit-1.2.5-R1.0.jar' OPTIONS='nogui' USERNAME='smith' # LIST ALL THE WORLDS IN YOUR CRAFTBUKKIT SERVER FOLDER WORLDS[1]='world' WORLDS[2]='world_nether' WORLDS[3]='world_the_end' WORLDS[4]='flat_world' MCPATH='/var/www/servers/Foundation' PLUGINSPATH='/var/www/servers/Foundation/plugins' TEMPPLUGINS='/var/www/servers/Foundationplugins/temp_plugins' BACKUPPATH='/var/www/servers/Foundation/backup' CPU_COUNT=2 INVOCATION="java -Xmx2024M -Xms2024M -XX:+UseConcMarkSweepGC -XX:+CMSIncrementalPacing -XX:ParallelGCThreads=$CPU_COUNT -XX:+AggressiveOpts -jar $SERVICE $OPTIONS" ME=`whoami` as_user() { if [ $ME == $USERNAME ] ; then bash -c "$1" else su - $USERNAME -c "$1" fi } mc_start() { if pgrep -u $USERNAME -f $SERVICE > /dev/null then echo "$SERVICE is already running!" else echo "Starting $SERVICE..." cd $MCPATH as_user "cd $MCPATH && screen -dmS craftbukkit $INVOCATION" sleep 7 if pgrep -u $USERNAME -f $SERVICE > /dev/null then echo "$SERVICE is now running." else echo "Error! Could not start $SERVICE!" fi fi } mc_saveoff() { if pgrep -u $USERNAME -f $SERVICE > /dev/null then echo "$SERVICE is running... suspending saves" as_user "screen -p 0 -S craftbukkit -X eval 'stuff \"say The server is preforming a backup. Server going to read-only mode. Do not build...\"\015'" as_user "screen -p 0 -S craftbukkit -X eval 'stuff \"save-off\"\015'" as_user "screen -p 0 -S craftbukkit -X eval 'stuff \"save-all\"\015'" sync sleep 10 else echo "$SERVICE is not running. Not suspending saves." fi } mc_save() { if pgrep -u $USERNAME -f $SERVICE > /dev/null then echo "$SERVICE is running... Saving worlds..." as_user "screen -p 0 -S craftbukkit -X eval 'stuff \"save-all\"\015'" sync sleep 10 echo "Save complete!" else echo "$SERVICE is not running. Cannot save!" fi } mc_saveon() { if pgrep -u $USERNAME -f $SERVICE > /dev/null then echo "$SERVICE is running... re-enabling saves" as_user "screen -p 0 -S craftbukkit -X eval 'stuff \"save-on\"\015'" as_user "screen -p 0 -S craftbukkit -X eval 'stuff \"say Server backup has completed. Server going to read-write mode. You can now continue building...\"\015'" else echo "$SERVICE is not running. Not resuming saves." fi } mc_stop() { if pgrep -u $USERNAME -f $SERVICE > /dev/null then echo "Stopping $SERVICE" as_user "screen -p 0 -S craftbukkit -X eval 'stuff \"say $SERVERNAME is shutting down in 30 seconds! Please stop what you are doing. Check back later, we'll be back!\"\015'" as_user "screen -p 0 -S craftbukkit -X eval 'stuff \"save-all\"\015'" sleep 30 as_user "screen -p 0 -S craftbukkit -X eval 'stuff \"stop\"\015'" sleep 7 else echo "$SERVICE was not running." fi if pgrep -u $USERNAME -f $SERVICE > /dev/null then echo "Error! $SERVICE could not be stopped." else echo "$SERVICE is stopped." fi } mc_update() { if pgrep -u $USERNAME -f $SERVICE > /dev/null then echo "$SERVICE is running! Will not start update." else MC_SERVER_URL=http://dl.bukkit.org/latest-rb/craftbukkit.jar as_user "cd $MCPATH && wget -q -O $MCPATH/craftbukkit_server.jar.update $MC_SERVER_URL" if [ -f $MCPATH/craftbukkit_server.jar.update ] then if `diff $MCPATH/$SERVICE $MCPATH/craftbukkit_server.jar.update >/dev/null` then echo "You are already running the latest version of $SERVICE. Update anyway? [Y/n]" select yn in "Yes" "No"; do case $yn in Yes ) as_user "mv $MCPATH/$SERVICE $MCPATH/${SERVICE}_old.jar" as_user "mv $MCPATH/craftbukkit_server.jar.update $MCPATH/$SERVICE" echo "$SERVICE updated successfully!"; break;; No ) echo "The update was not installed! Removing temporary files and exiting..." as_user "rm $MCPATH/craftbukkit_server.jar.update" exit;; esac done else as_user "mv $MCPATH/$SERVICE $MCPATH/${SERVICE}_old.jar" as_user "mv $MCPATH/craftbukkit_server.jar.update $MCPATH/$SERVICE" echo "$SERVICE updated successfully!" fi else echo "$SERVICE update could not be downloaded." fi fi } mc_addplugin() { if pgrep -u $USERNAME -f $SERVICE > /dev/null then echo "$SERVICE is running! Please stop the service before adding a plugin." else echo "Paste the URL to the .JAR Plugin..." read JARURL JARNAME=$(basename "$JARURL") if [ -d "$TEMPPLUGINS" ] then as_user "cd $PLUGINSPATH && wget -r -A.jar $JARURL -o temp_plugins/$JARNAME" else as_user "cd $PLUGINSPATH && mkdir $TEMPPLUGINS && wget -r -A.jar $JARURL -o temp_plugins/$JARNAME" fi if [ -f "$TMPDIR/$JARNAME" ] then if [ -f "$PLUGINSPATH/$JARNAME" ] then if `diff $PLUGINSPATH/$JARNAME $TMPDIR/$JARNAME >/dev/null` then echo "You are already running the latest version of $JARNAME." else NOW=`date "+%Y-%m-%d_%Hh%M"` echo "Are you sure you want to overwrite this plugin? [Y/n]" echo "Note: Your old plugin will be moved to the "$TEMPPLUGINS" folder with todays date." select yn in "Yes" "No"; do case $yn in Yes ) as_user "mv $PLUGINSPATH/$JARNAME $TEMPPLUGINS/${JARNAME}_${NOW} && mv $TEMPPLUGINS/$JARNAME $PLUGINSPATH/$JARNAME"; break;; No ) echo "The plugin has not been installed! Removing temporary plugin and exiting..." as_user "rm $TEMPPLUGINS/$JARNAME"; exit;; esac done echo "Would you like to start the $SERVICE now? [Y/n]" select yn in "Yes" "No"; do case $yn in Yes ) mc_start; break;; No ) "$SERVICE not running! To start the service run: /etc/init.d/craftbukkit start"; exit;; esac done fi else echo "Are you sure you want to add this new plugin? [Y/n]" select yn in "Yes" "No"; do case $yn in Yes ) as_user "mv $PLUGINSPATH/$JARNAME $TEMPPLUGINS/${JARNAME}_${NOW} && mv $TEMPPLUGINS/$JARNAME $PLUGINSPATH/$JARNAME"; break;; No ) echo "The plugin has not been installed! Removing temporary plugin and exiting..." as_user "rm $TEMPPLUGINS/$JARNAME"; exit;; esac done echo "Would you like to start the $SERVICE now? [Y/n]?" select yn in "Yes" "No"; do case $yn in Yes ) mc_start; break;; No ) "$SERVICE not running! To start the service run: /etc/init.d/craftbukkit start"; exit;; esac done fi else echo "Failed to download the plugin from the URL you specified!" exit; fi fi } mc_scanplugins() { if [ "$(ls -A $PLUGINSPATH)" ] then shopt -s nullglob PLUGINS=($PLUGINSPATH/*.jar) i=1 for f in "${PLUGINS[@]}" do echo "${i}: $f" PLUGIN[$i]=$f i=$(( $i + 1 )) done echo "Enter the ID of a plugin you want removed, or any other key to cancel." read INPUT if [ ! -z "${INPUT##*[!0-9]*}" ] then if [ -f "${PLUGIN[INPUT]}" ] then echo "Removing plugin..." JAR=$(basename ${PLUGIN[INPUT]}) JARNAME=${JAR%.jar} as_user "rm -f ${PLUGIN[INPUT]}" sleep 2 as_user "cd $PLUGINSPATH && rm -rf ./${JARNAME}" if [ -f "${PLUGINSPATH}/${JARNAME}" ] then echo "Plugin folder could not be removed..." fi echo "Plugin removed." else echo "${PLUGIN[INPUT]}" echo "Invalid plugin! Does not exist! Canceling..." exit; fi else echo "Canceling..." exit; fi else echo "You have no plugins installed." exit; fi } mc_backup() { mc_saveoff for i in "${WORLDS[@]}"; do NOW=`date "+%Y-%m-%d_%Hh%M"` BACKUP_FILE="$BACKUPPATH/${i}_${NOW}.tar" echo "Backing up world: $i..." #as_user "cd $MCPATH && cp -r $i $BACKUPPATH/${i}_`date "+%Y.%m.%d_%H.%M""` as_user "tar -C \"$MCPATH\" -cf \"$BACKUP_FILE\" $i" done echo "Backing up $SERVICE" as_user "tar -C \"$MCPATH\" -rf \"$BACKUP_FILE\" $SERVICE" #as_user "cp \"$MCPATH/$SERVICE\" \"$BACKUPPATH/craftbukkit_server_${NOW}.jar\"" mc_saveon echo "Compressing backup..." as_user "tar -cvzf $BACKUPPATH/server_backup_${NOW}.tar.gz $MCPATH" echo "Backup has completed successfully." } mc_command() { command="$1"; if pgrep -u $USERNAME -f $SERVICE > /dev/null then pre_log_len=`wc -l "$MCPATH/server.log" | awk '{print $1}'` echo "$SERVICE is running... executing command" as_user "screen -p 0 -S craftbukkit -X eval 'stuff \"$command\"\015'" sleep .1 # assumes that the command will run and print to the log file in less than .1 seconds # print output tail -n $[`wc -l "$MCPATH/server.log" | awk '{print $1}'`-$pre_log_len] "$MCPATH/server.log" fi } #Start-Stop here case "$1" in start) mc_start ;; stop) mc_stop ;; restart) mc_stop mc_start ;; save) mc_save ;; update) mc_stop mc_backup mc_update mc_start ;; scanplugins) mc_scanplugins ;; addplugin) mc_addplugin ;; backup) mc_backup ;; status) if pgrep -u $USERNAME -f $SERVICE > /dev/null then echo "$SERVICE is running." else echo "$SERVICE is not running." fi ;; command) if [ $# -gt 1 ]; then shift mc_command "$*" else echo "Must specify server command (try 'help'?)" fi ;; *) echo "Usage: $0 {start|stop|update|backup|status|restart|command \"server command\"}" exit 1 ;; esac exit 0

  Read the article

• C#/.NET Little Wonders: Constraining Generics with Where Clause

  - by James Michael Hare

  Back when I was primarily a C++ developer, I loved C++ templates.  The power of writing very reusable generic classes brought the art of programming to a brand new level.  Unfortunately, when .NET 1.0 came about, they didn’t have a template equivalent.  With .NET 2.0 however, we finally got generics, which once again let us spread our wings and program more generically in the world of .NET However, C# generics behave in some ways very differently from their C++ template cousins.  There is a handy clause, however, that helps you navigate these waters to make your generics more powerful. The Problem – C# Assumes Lowest Common Denominator In C++, you can create a template and do nearly anything syntactically possible on the template parameter, and C++ will not check if the method/fields/operations invoked are valid until you declare a realization of the type.  Let me illustrate with a C++ example: 1: // compiles fine, C++ makes no assumptions as to T 2: template <typename T> 3: class ReverseComparer 4: { 5: public: 6: int Compare(const T& lhs, const T& rhs) 7: { 8: return rhs.CompareTo(lhs); 9: } 10: }; Notice that we are invoking a method CompareTo() off of template type T.  Because we don’t know at this point what type T is, C++ makes no assumptions and there are no errors. C++ tends to take the path of not checking the template type usage until the method is actually invoked with a specific type, which differs from the behavior of C#: 1: // this will NOT compile! C# assumes lowest common denominator. 2: public class ReverseComparer<T> 3: { 4: public int Compare(T lhs, T rhs) 5: { 6: return lhs.CompareTo(rhs); 7: } 8: } So why does C# give us a compiler error even when we don’t yet know what type T is?  This is because C# took a different path in how they made generics.  Unless you specify otherwise, for the purposes of the code inside the generic method, T is basically treated like an object (notice I didn’t say T is an object). That means that any operations, fields, methods, properties, etc that you attempt to use of type T must be available at the lowest common denominator type: object.  Now, while object has the broadest applicability, it also has the fewest specific.  So how do we allow our generic type placeholder to do things more than just what object can do? Solution: Constraint the Type With Where Clause So how do we get around this in C#?  The answer is to constrain the generic type placeholder with the where clause.  Basically, the where clause allows you to specify additional constraints on what the actual type used to fill the generic type placeholder must support. You might think that narrowing the scope of a generic means a weaker generic.  In reality, though it limits the number of types that can be used with the generic, it also gives the generic more power to deal with those types.  In effect these constraints says that if the type meets the given constraint, you can perform the activities that pertain to that constraint with the generic placeholders. Constraining Generic Type to Interface or Superclass One of the handiest where clause constraints is the ability to specify the type generic type must implement a certain interface or be inherited from a certain base class. For example, you can’t call CompareTo() in our first C# generic without constraints, but if we constrain T to IComparable<T>, we can: 1: public class ReverseComparer<T> 2: where T : IComparable<T> 3: { 4: public int Compare(T lhs, T rhs) 5: { 6: return lhs.CompareTo(rhs); 7: } 8: } Now that we’ve constrained T to an implementation of IComparable<T>, this means that our variables of generic type T may now call any members specified in IComparable<T> as well.  This means that the call to CompareTo() is now legal. If you constrain your type, also, you will get compiler warnings if you attempt to use a type that doesn’t meet the constraint.  This is much better than the syntax error you would get within C++ template code itself when you used a type not supported by a C++ template. Constraining Generic Type to Only Reference Types Sometimes, you want to assign an instance of a generic type to null, but you can’t do this without constraints, because you have no guarantee that the type used to realize the generic is not a value type, where null is meaningless. Well, we can fix this by specifying the class constraint in the where clause.  By declaring that a generic type must be a class, we are saying that it is a reference type, and this allows us to assign null to instances of that type: 1: public static class ObjectExtensions 2: { 3: public static TOut Maybe<TIn, TOut>(this TIn value, Func<TIn, TOut> accessor) 4: where TOut : class 5: where TIn : class 6: { 7: return (value != null) ? accessor(value) : null; 8: } 9: } In the example above, we want to be able to access a property off of a reference, and if that reference is null, pass the null on down the line.  To do this, both the input type and the output type must be reference types (yes, nullable value types could also be considered applicable at a logical level, but there’s not a direct constraint for those). Constraining Generic Type to only Value Types Similarly to constraining a generic type to be a reference type, you can also constrain a generic type to be a value type.  To do this you use the struct constraint which specifies that the generic type must be a value type (primitive, struct, enum, etc). Consider the following method, that will convert anything that is IConvertible (int, double, string, etc) to the value type you specify, or null if the instance is null. 1: public static T? ConvertToNullable<T>(IConvertible value) 2: where T : struct 3: { 4: T? result = null; 5:  6: if (value != null) 7: { 8: result = (T)Convert.ChangeType(value, typeof(T)); 9: } 10:  11: return result; 12: } Because T was constrained to be a value type, we can use T? (System.Nullable<T>) where we could not do this if T was a reference type. Constraining Generic Type to Require Default Constructor You can also constrain a type to require existence of a default constructor.  Because by default C# doesn’t know what constructors a generic type placeholder does or does not have available, it can’t typically allow you to call one.  That said, if you give it the new() constraint, it will mean that the type used to realize the generic type must have a default (no argument) constructor. Let’s assume you have a generic adapter class that, given some mappings, will adapt an item from type TFrom to type TTo.  Because it must create a new instance of type TTo in the process, we need to specify that TTo has a default constructor: 1: // Given a set of Action<TFrom,TTo> mappings will map TFrom to TTo 2: public class Adapter<TFrom, TTo> : IEnumerable<Action<TFrom, TTo>> 3: where TTo : class, new() 4: { 5: // The list of translations from TFrom to TTo 6: public List<Action<TFrom, TTo>> Translations { get; private set; } 7:  8: // Construct with empty translation and reverse translation sets. 9: public Adapter() 10: { 11: // did this instead of auto-properties to allow simple use of initializers 12: Translations = new List<Action<TFrom, TTo>>(); 13: } 14:  15: // Add a translator to the collection, useful for initializer list 16: public void Add(Action<TFrom, TTo> translation) 17: { 18: Translations.Add(translation); 19: } 20:  21: // Add a translator that first checks a predicate to determine if the translation 22: // should be performed, then translates if the predicate returns true 23: public void Add(Predicate<TFrom> conditional, Action<TFrom, TTo> translation) 24: { 25: Translations.Add((from, to) => 26: { 27: if (conditional(from)) 28: { 29: translation(from, to); 30: } 31: }); 32: } 33:  34: // Translates an object forward from TFrom object to TTo object. 35: public TTo Adapt(TFrom sourceObject) 36: { 37: var resultObject = new TTo(); 38:  39: // Process each translation 40: Translations.ForEach(t => t(sourceObject, resultObject)); 41:  42: return resultObject; 43: } 44:  45: // Returns an enumerator that iterates through the collection. 46: public IEnumerator<Action<TFrom, TTo>> GetEnumerator() 47: { 48: return Translations.GetEnumerator(); 49: } 50:  51: // Returns an enumerator that iterates through a collection. 52: IEnumerator IEnumerable.GetEnumerator() 53: { 54: return GetEnumerator(); 55: } 56: } Notice, however, you can’t specify any other constructor, you can only specify that the type has a default (no argument) constructor. Summary The where clause is an excellent tool that gives your .NET generics even more power to perform tasks higher than just the base "object level" behavior.  There are a few things you cannot specify with constraints (currently) though: Cannot specify the generic type must be an enum. Cannot specify the generic type must have a certain property or method without specifying a base class or interface – that is, you can’t say that the generic must have a Start() method. Cannot specify that the generic type allows arithmetic operations. Cannot specify that the generic type requires a specific non-default constructor. In addition, you cannot overload a template definition with different, opposing constraints.  For example you can’t define a Adapter<T> where T : struct and Adapter<T> where T : class.  Hopefully, in the future we will get some of these things to make the where clause even more useful, but until then what we have is extremely valuable in making our generics more user friendly and more powerful!   Technorati Tags: C#,.NET,Little Wonders,BlackRabbitCoder,where,generics

  Read the article

• Configure Exchange For Windows Mobile

  - by Richard Jones

  http://wmexchangesetup.com/launcher.aspx A very useful guide. Hat Tip – Mr Peter Foot.

  Read the article

• I want to trace the activity of my customize link sent via email or on chat to my custome

  - by anilkumble789

  I want to trace the activity of my customize link sent via email or on chat to my customer. Activity like : whether they opened the link or not? How much time they were on page? examples: I have decided to sent business proposal link to Mr.ABC and Mr.XYZ So, for ABC the link would be like : www.mycompany.com/proposal ....abc... So, for XYZ the link would be like : www.mycompany.com/proposal ....xyz... its like link analytic. How to go ahead with with it?

  Read the article

• Adding multiple data importers support to web applications

  - by DigiMortal

  I’m building web application for customer and there is requirement that users must be able to import data in different formats. Today we will support XLSX and ODF as import formats and some other formats are waiting. I wanted to be able to add new importers on the fly so I don’t have to deploy web application again when I add new importer or change some existing one. In this posting I will show you how to build generic importers support to your web application. Importer interface All importers we use must have something in common so we can easily detect them. To keep things simple I will use interface here. public interface IMyImporter {     string[] SupportedFileExtensions { get; }     ImportResult Import(Stream fileStream, string fileExtension); } Our interface has the following members: SupportedFileExtensions – string array of file extensions that importer supports. This property helps us find out what import formats are available and which importer to use with given format. Import – method that does the actual importing work. Besides file we give in as stream we also give file extension so importer can decide how to handle the file. It is enough to get started. When building real importers I am sure you will switch over to abstract base class. Importer class Here is sample importer that imports data from Excel and Word documents. Importer class with no implementation details looks like this: public class MyOpenXmlImporter : IMyImporter {     public string[] SupportedFileExtensions     {         get { return new[] { "xlsx", "docx" }; }     }     public ImportResult Import(Stream fileStream, string extension)     {         // ...     } } Finding supported import formats in web application Now we have importers created and it’s time to add them to web application. Usually we have one page or ASP.NET MVC controller where we need importers. To this page or controller we add the following method that uses reflection to find all classes that implement our IMyImporter interface. private static string[] GetImporterFileExtensions() {     var types = from a in AppDomain.CurrentDomain.GetAssemblies()                 from t in a.GetTypes()                 where t.GetInterfaces().Contains(typeof(IMyImporter))                 select t;       var extensions = new Collection<string>();     foreach (var type in types)     {         var instance = (IMyImporter)type.InvokeMember(null,                        BindingFlags.CreateInstance, null, null, null);           foreach (var extension in instance.SupportedFileExtensions)         {             if (extensions.Contains(extension))                 continue;               extensions.Add(extension);         }     }       return extensions.ToArray(); } This code doesn’t look nice and is far from optimal but it works for us now. It is possible to improve performance of web application if we cache extensions and their corresponding types to some static dictionary. We have to fill it only once because our application is restarted when something changes in bin folder. Finding importer by extension When user uploads file we need to detect the extension of file and find the importer that supports given extension. We add another method to our page or controller that uses reflection to return us importer instance or null if extension is not supported. private static IMyImporter GetImporterForExtension(string extensionToFind) {     var types = from a in AppDomain.CurrentDomain.GetAssemblies()                 from t in a.GetTypes()                 where t.GetInterfaces().Contains(typeof(IMyImporter))                 select t;     foreach (var type in types)     {         var instance = (IMyImporter)type.InvokeMember(null,                        BindingFlags.CreateInstance, null, null, null);           if (instance.SupportedFileExtensions.Contains(extensionToFind))         {             return instance;         }     }       return null; } Here is example ASP.NET MVC controller action that accepts uploaded file, finds importer that can handle file and imports data. Again, this is sample code I kept minimal to better illustrate how things work. public ActionResult Import(MyImporterModel model) {     var file = Request.Files[0];     var extension = Path.GetExtension(file.FileName).ToLower();     var importer = GetImporterForExtension(extension.Substring(1));     var result = importer.Import(file.InputStream, extension);     if (result.Errors.Count > 0)     {         foreach (var error in result.Errors)             ModelState.AddModelError("file", error);           return Import();     }     return RedirectToAction("Index"); } Conclusion That’s it. Using couple of ugly methods and one simple interface we were able to add importers support to our web application. Example code here is not perfect but it works. It is possible to cache mappings between file extensions and importer types to some static variable because changing of these mappings means that something is changed in bin folder of web application and web application is restarted in this case anyway.

  Read the article

• Java Program help [migrated]

  - by georgetheevilman

  Okay I have a really annoying error. Its coming from my retainAll method. The problem is that I am outputting 1,3,5 in ints at the end, but I need 1,3,5,7,9. Here is the code below for the MySet and driver classes public class MySetTester { public static void main(String[]args) { MySet<String> strings = new MySet<String>(); strings.add("Hey!"); strings.add("Hey!"); strings.add("Hey!"); strings.add("Hey!"); strings.add("Hey!"); strings.add("Listen!"); strings.add("Listen!"); strings.add("Sorry, I couldn't resist."); strings.add("Sorry, I couldn't resist."); strings.add("(you know you would if you could)"); System.out.println("Testing add:\n"); System.out.println("Your size: " + strings.size() + ", contains(Sorry): " + strings.contains("Sorry, I couldn't resist.")); System.out.println("Exp. size: 4, contains(Sorry): true\n"); MySet<String> moreStrings = new MySet<String>(); moreStrings.add("Sorry, I couldn't resist."); moreStrings.add("(you know you would if you could)"); strings.removeAll(moreStrings); System.out.println("Testing remove and removeAll:\n"); System.out.println("Your size: " + strings.size() + ", contains(Sorry): " + strings.contains("Sorry, I couldn't resist.")); System.out.println("Exp. size: 2, contains(Sorry): false\n"); MySet<Integer> ints = new MySet<Integer>(); for (int i = 0; i < 100; i++) { ints.add(i); } System.out.println("Your size: " + ints.size()); System.out.println("Exp. size: 100\n"); for (int i = 0; i < 100; i += 2) { ints.remove(i); } System.out.println("Your size: " + ints.size()); System.out.println("Exp. size: 50\n"); MySet<Integer> zeroThroughNine = new MySet<Integer>(); for (int i = 0; i < 10; i++) { zeroThroughNine.add(i); } ints.retainAll(zeroThroughNine); System.out.println("ints should now only retain odd numbers" + " 0 through 10\n"); System.out.println("Testing your iterator:\n"); for (Integer i : ints) { System.out.println(i); } System.out.println("\nExpected: \n\n1 \n3 \n5 \n7 \n9\n"); System.out.println("Yours:"); for (String s : strings) { System.out.println(s); } System.out.println("\nExpected: \nHey! \nListen!"); strings.clear(); System.out.println("\nClearing your set...\n"); System.out.println("Your set is empty: " + strings.isEmpty()); System.out.println("Exp. set is empty: true"); } } And here is the main code. But still read the top part because that's where my examples are. import java.util.Set; import java.util.Collection; import java.lang.Iterable; import java.util.Iterator; import java.util.Arrays; import java.lang.reflect.Array; public class MySet implements Set, Iterable { // instance variables - replace the example below with your own private E[] backingArray; private int numElements; /** * Constructor for objects of class MySet */ public MySet() { backingArray=(E[]) new Object[5]; numElements=0; } public boolean add(E e){ for(Object elem:backingArray){ if (elem==null ? e==null : elem.equals(e)){ return false; } } if(numElements==backingArray.length){ E[] newArray=Arrays.copyOf(backingArray,backingArray.length*2); newArray[numElements]=e; numElements=numElements+1; backingArray=newArray; return true; } else{ backingArray[numElements]=e; numElements=numElements+1; return true; } } public boolean addAll(Collection<? extends E> c){ for(E elem:c){ this.add(elem); } return true; } public void clear(){ E[] newArray=(E[])new Object[backingArray.length]; numElements=0; backingArray=newArray; } public boolean equals(Object o){ if(o instanceof Set &&(((Set)o).size()==numElements)){ for(E elem:(Set<E>)o){ if (this.contains(o)==false){ return false; } return true; } } return false; } public boolean contains(Object o){ for(E backingElem:backingArray){ if (o!=null && o.equals(backingElem)){ return true; } } return false; } public boolean containsAll(Collection<?> c){ for(E elem:(Set<E>)c){ if(!(this.contains(elem))){ return false; } } return true; } public int hashCode(){ int sum=0; for(E elem:backingArray){ if(elem!=null){ sum=sum+elem.hashCode(); } } return sum; } public boolean isEmpty(){ if(numElements==0){ return true; } else{ return false; } } public boolean remove(Object o){ int i=0; for(Object elem:backingArray){ if(o!=null && o.equals(elem)){ backingArray[i]=null; numElements=numElements-1; E[] newArray=Arrays.copyOf(backingArray,backingArray.length-1); return true; } i=i+1; } return false; } public boolean removeAll(Collection<?> c){ for(Object elem:c){ this.remove(elem); } return true; } public boolean retainAll(Collection<?> c){ MySet<E> removalArray=new MySet<E>(); for(E arrayElem:backingArray){ if(arrayElem!= null && !(c.contains(arrayElem))){ this.remove(arrayElem); } } return false; } public int size(){ return numElements; } public <T> T[] toArray(T[] a) throws ArrayStoreException,NullPointerException{ for(int i=0;i<numElements;i++){ a[i]=(T)backingArray[i]; } for(int j=numElements;j<a.length;j++){ a[j]=null; } return a; } public Object[] toArray(){ Object[] newArray=new Object[numElements]; for(int i=0;i<numElements;i++){ newArray[i]=backingArray[i]; } return newArray; } public Iterator<E> iterator(){ setIterator iterator=new setIterator(); return iterator; } private class setIterator implements Iterator<E>{ private int currIndex; private E lastElement; public setIterator(){ currIndex=0; lastElement=null; } public boolean hasNext(){ while(currIndex<=numElements && backingArray[currIndex]==null){ currIndex=currIndex+1; } if (currIndex<=numElements){ return true; } return false; } public E next(){ E element=backingArray[currIndex]; currIndex=currIndex+1; lastElement=element; return element; } public void remove() throws UnsupportedOperationException,IllegalStateException{ if(lastElement!=null){ MySet.this.remove((Object)lastElement); numElements=numElements-1; } else{ throw new IllegalStateException(); } } } } I've been able to reduce the problems, but otherwise this thing is still causing problems.

  Read the article

• How do I sign my certificate using the root certificate

  - by Asif Alam

  I am using certificate based authentication between my server and client. I have generated Root Certificate. My client at the time of installation will generate a new Certificate and use the Root Certificate to sign it. I need to use Windows API. Cannot use any windows tools like makecert. Till now I have been able to Install the Root certificate in store. Below code X509Certificate2 ^ certificate = gcnew X509Certificate2("C:\\rootcert.pfx","test123"); X509Store ^ store = gcnew X509Store( "teststore",StoreLocation::CurrentUser ); store->Open( OpenFlags::ReadWrite ); store->Add( certificate ); store->Close(); Then open the installed root certificate to get the context GetRootCertKeyInfo(){ HCERTSTORE hCertStore; PCCERT_CONTEXT pSignerCertContext=NULL; DWORD dwSize = NULL; CRYPT_KEY_PROV_INFO* pKeyInfo = NULL; DWORD dwKeySpec; if ( !( hCertStore = CertOpenStore(CERT_STORE_PROV_SYSTEM, 0, NULL, CERT_SYSTEM_STORE_CURRENT_USER,L"teststore"))) { _tprintf(_T("Error 0x%x\n"), GetLastError()); } pSignerCertContext = CertFindCertificateInStore(hCertStore,MY_ENCODING_TYPE,0,CERT_FIND_ANY,NULL,NULL); if(NULL == pSignerCertContext) { _tprintf(_T("Error 0x%x\n"), GetLastError()); } if(!(CertGetCertificateContextProperty( pSignerCertContext, CERT_KEY_PROV_INFO_PROP_ID, NULL, &dwSize))) { _tprintf(_T("Error 0x%x\n"), GetLastError()); } if(pKeyInfo) free(pKeyInfo); if(!(pKeyInfo = (CRYPT_KEY_PROV_INFO*)malloc(dwSize))) { _tprintf(_T("Error 0x%x\n"), GetLastError()); } if(!(CertGetCertificateContextProperty( pSignerCertContext, CERT_KEY_PROV_INFO_PROP_ID, pKeyInfo, &dwSize))) { _tprintf(_T("Error 0x%x\n"), GetLastError()); } return pKeyInfo; } Then finally created the certificate and signed with the pKeyInfo // Acquire key container if (!CryptAcquireContext(&hCryptProv, _T("trykeycon"), NULL, PROV_RSA_FULL, CRYPT_MACHINE_KEYSET)) { _tprintf(_T("Error 0x%x\n"), GetLastError()); // Try to create a new key container _tprintf(_T("CryptAcquireContext... ")); if (!CryptAcquireContext(&hCryptProv, _T("trykeycon"), NULL, PROV_RSA_FULL, CRYPT_NEWKEYSET | CRYPT_MACHINE_KEYSET)) { _tprintf(_T("Error 0x%x\n"), GetLastError()); return 0; } else { _tprintf(_T("Success\n")); } } else { _tprintf(_T("Success\n")); } // Generate new key pair _tprintf(_T("CryptGenKey... ")); if (!CryptGenKey(hCryptProv, AT_SIGNATURE, 0x08000000 /*RSA-2048-BIT_KEY*/, &hKey)) { _tprintf(_T("Error 0x%x\n"), GetLastError()); return 0; } else { _tprintf(_T("Success\n")); } //some code CERT_NAME_BLOB SubjectIssuerBlob; memset(&SubjectIssuerBlob, 0, sizeof(SubjectIssuerBlob)); SubjectIssuerBlob.cbData = cbEncoded; SubjectIssuerBlob.pbData = pbEncoded; // Prepare algorithm structure for self-signed certificate CRYPT_ALGORITHM_IDENTIFIER SignatureAlgorithm; memset(&SignatureAlgorithm, 0, sizeof(SignatureAlgorithm)); SignatureAlgorithm.pszObjId = szOID_RSA_SHA1RSA; // Prepare Expiration date for self-signed certificate SYSTEMTIME EndTime; GetSystemTime(&EndTime); EndTime.wYear += 5; // Create self-signed certificate _tprintf(_T("CertCreateSelfSignCertificate... ")); CRYPT_KEY_PROV_INFO* aKeyInfo; aKeyInfo = GetRootCertKeyInfo(); pCertContext = CertCreateSelfSignCertificate(NULL, &SubjectIssuerBlob, 0, aKeyInfo, &SignatureAlgorithm, 0, &EndTime, 0); With the above code I am able to create the certificate but it does not looks be signed by the root certificate. I am unable to figure what I did is right or not.. Any help with be greatly appreciated.. Thanks Asif

  Read the article

• Why can't I reference child entities with part of the parent entities composite key

  - by tigermain

  I am trying to reference some child entities with part of the parents composite key not all of it, why cant I? This happens when I use the following mapping instead of that which is commented. I get the following error Foreign key in table VolatileEventContent must have same number of columns as referenced primary key in table LocationSearchView <?xml version="1.0" encoding="utf-8" ?> <hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" namespace="JeanieMaster.Domain.Entities" assembly="JeanieMaster.Domain"> <class name="LocationSearchView" table="LocationSearchView"> <composite-id> <key-property name="LocationId" type="Int32"></key-property> <key-property name="ContentProviderId" type="Int32"></key-property> <key-property name="CategoryId" type="Int32"></key-property> </composite-id> <property name="CompanyName" type="String" not-null="true" update="false" insert="false"/> <property name="Description" type="String" not-null="true" update="false" insert="false"/> <property name="CategoryId" type="Int32" not-null="true" update="false" insert="false"/> <property name="ContentProviderId" type="Int32" not-null="true" update="false" insert="false"/> <property name="LocationId" type="Int32" not-null="true" update="false" insert="false"/> <property name="Latitude" type="Double" update="false" insert="false" /> <property name="Longitude" type="Double" update="false" insert="false" /> <bag name="Events" table="VolatileEventContent" where="DeactivatedOn IS NULL" order-by="StartDate DESC" lazy="false" cascade="none"> <key> <column name="LocationId"></column> <column name="ContentProviderId"></column> <!--<column name="LocationId"></column> <column name="ContentProviderId"></column> <column name="CategoryId"></column>--> </key> <one-to-many class="Event" column="VolatileEventContentId"></one-to-many> </bag> </class> </hibernate-mapping> And VolatileEventContent mapping file <?xml version="1.0" encoding="utf-8" ?> <hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" namespace="JeanieMaster.Domain.Entities" assembly="JeanieMaster.Domain"> <class name="Event" table="VolatileEventContent" select-before-update="false" optimistic-lock="none"> <composite-id> <key-property name="LocationId" type="Int32"></key-property> <key-property name="ContentProviderId" type="Int32"></key-property> </composite-id> <property name="Description" type="String" not-null="true" update="false" insert="false"/> <property name="StartDate" type="DateTime" not-null="true" update="false" insert="false" /> <property name="EndDate" type="DateTime" not-null="true" update="false" insert="false" /> <property name="CreatedOn" type="DateTime" not-null="true" update="false" insert="false" /> <property name="ModifiedOn" type="DateTime" not-null="false" update="false" insert="false" /> <many-to-one name="Location" class="Location" column="LocationId" /> <bag name="Artistes" table="EventArtiste" lazy="false" cascade="none"> <key name="VolatileEventContentId" /> <many-to-many class="Artiste" column="ArtisteId" ></many-to-many> </bag> </class> </hibernate-mapping>

  Read the article

• My VARCHAR(MAX) field is capping itself at 4000; what gives?

  - by eidylon

  Hello all... I have a table in one of my databases which is a queue of emails. Emails to certain addresses get accumulated into one email, which is done by a sproc. In the sproc, I have a table variable which I use to build the accumulated bodies of the emails, and then loop through to send each email. In my table var I have my body column defined as VARCHAR(MAX), seeing as there could be any number of emails currently accumulated for a given email address. It seems though that even though my column is defined as VARCHAR(MAX) it is behaving as if it were VARCHAR(4000) and is truncating the data going into it, although it does NOT throw any exceptions, it just silently stops concatenating any more data after 4000 characters. The MERGE statement is where it is building the accumulated email body into @EMAILS.BODY, which is the field that is truncating itself at 4000 characters. Below is the code of my sproc... ALTER PROCEDURE [system].[SendAccumulatedEmails] AS BEGIN SET NOCOUNT ON; DECLARE @SENTS BIGINT = 0; DECLARE @ROWS TABLE ( ROWID ROWID, DATED DATETIME, ADDRESS NAME, SUBJECT VARCHAR(1000), BODY VARCHAR(MAX) ) INSERT INTO @ROWS SELECT ROWID, DATED, ADDRESS, SUBJECT, BODY FROM system.EMAILQUEUE WHERE ACCUMULATE = 1 AND SENT IS NULL ORDER BY ADDRESS, DATED DECLARE @EMAILS TABLE ( ADDRESS NAME, ALLIDS VARCHAR(1000), BODY VARCHAR(MAX) ) DECLARE @PRVRID ROWID = NULL, @CURRID ROWID = NULL SELECT @CURRID = MIN(ROWID) FROM @ROWS WHILE @CURRID IS NOT NULL BEGIN MERGE @EMAILS AS DST USING (SELECT * FROM @ROWS WHERE ROWID = @CURRID) AS SRC ON SRC.ADDRESS = DST.ADDRESS WHEN MATCHED THEN UPDATE SET DST.ALLIDS = DST.ALLIDS + ', ' + CONVERT(VARCHAR,ROWID), DST.BODY = DST.BODY + '<i>'+CONVERT(VARCHAR,SRC.DATED,101)+' ' +CONVERT(VARCHAR,SRC.DATED,8) +':</i> <b>'+SRC.SUBJECT+'</b>'+CHAR(13)+SRC.BODY +' (Message ID '+CONVERT(VARCHAR,SRC.ROWID)+')' +CHAR(13)+CHAR(13) WHEN NOT MATCHED BY TARGET THEN INSERT (ADDRESS, ALLIDS, BODY) VALUES ( SRC.ADDRESS, CONVERT(VARCHAR,ROWID), '<i>'+CONVERT(VARCHAR,SRC.DATED,101)+' ' +CONVERT(VARCHAR,SRC.DATED,8)+':</i> <b>' +SRC.SUBJECT+'</b>'+CHAR(13)+SRC.BODY +' (Message ID '+CONVERT(VARCHAR,SRC.ROWID)+')' +CHAR(13)+CHAR(13)); SELECT @PRVRID = @CURRID, @CURRID = NULL SELECT @CURRID = MIN(ROWID) FROM @ROWS WHERE ROWID > @PRVRID END DECLARE @MAILFROM VARCHAR(100) = system.getOption('MAILFROM'), DECLARE @SMTPHST VARCHAR(100) = system.getOption('SMTPSERVER'), DECLARE @SMTPUSR VARCHAR(100) = system.getOption('SMTPUSER'), DECLARE @SMTPPWD VARCHAR(100) = system.getOption('SMTPPASS') DECLARE @ADDRESS NAME, @BODY VARCHAR(MAX), @ADDL VARCHAR(MAX) DECLARE @SUBJECT VARCHAR(1000) = 'Accumulated Emails from LIJSL' DECLARE @PRVID NAME = NULL, @CURID NAME = NULL SELECT @CURID = MIN(ADDRESS) FROM @EMAILS WHILE @CURID IS NOT NULL BEGIN SELECT @ADDRESS = ADDRESS, @BODY = BODY FROM @EMAILS WHERE ADDRESS = @CURID SELECT @BODY = @BODY + 'This is an automated message sent from an unmonitored mailbox.'+CHAR(13)+'Do not reply to this message; your message will not be read.' SELECT @BODY = '<style type="text/css"> * {font-family: Tahoma, Arial, Verdana;} p {margin-top: 10px; padding-top: 10px; border-top: single 1px dimgray;} p:first-child {margin-top: 10px; padding-top: 0px; border-top: none 0px transparent;} </style>' + @BODY exec system.LogIt @SUBJECT, @BODY BEGIN TRY exec system.SendMail @SMTPHST, @SMTPUSR, @SMTPPWD, @MAILFROM, @ADDRESS, NULL, NULL, @SUBJECT, @BODY, 1 END TRY BEGIN CATCH DECLARE @EMSG NVARCHAR(2048) = 'system.EMAILQUEUE.AI:'+ERROR_MESSAGE() SELECT @ADDL = 'TO:'+@ADDRESS+CHAR(13)+'SUBJECT:'+@SUBJECT+CHAR(13)+'BODY:'+@BODY exec system.LogIt @EMSG,@ADDL END CATCH SELECT @PRVID = @CURID, @CURID = NULL SELECT @CURID = MIN(ADDRESS) FROM @EMAILS WHERE ADDRESS > @PRVID END UPDATE system.EMAILQUEUE SET SENT = getdate() FROM system.EMAILQUEUE E, @ROWS R WHERE E.ROWID = R.ROWID END

  Read the article

• 1>main.obj : error LNK2001: unresolved external symbol _D3D10CreateDeviceAndSwapChain@32

  - by numerical25

  having trouble getting my directx going I get the following error 1>Linking... 1>main.obj : error LNK2001: unresolved external symbol _D3D10CreateDeviceAndSwapChain@32 1>C:\Users\numerical25\Desktop\Intro ToDirectX\msdnTutorials\tutorial0\tutorial\Debug\tutorial.exe : fatal error LNK1120: 1 unresolved externals below is my code // include the basic windows header file #include <windows.h> #include <windowsx.h> #include <d3d10.h> ID3D10Device* g_pd3dDevice; IDXGISwapChain* g_pSwapChain; // the WindowProc function prototype LRESULT CALLBACK WindowProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam); bool InitDirect3D(HWND); // the entry point for any Windows program int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow) { // the handle for the window, filled by a function HWND hWnd; // this struct holds information for the window class WNDCLASSEX wc; // clear out the window class for use ZeroMemory(&wc, sizeof(WNDCLASSEX)); // fill in the struct with the needed information wc.cbSize = sizeof(WNDCLASSEX); wc.style = CS_HREDRAW | CS_VREDRAW; wc.lpfnWndProc = WindowProc; wc.hInstance = hInstance; wc.hCursor = LoadCursor(NULL, IDC_ARROW); wc.hbrBackground = (HBRUSH)COLOR_WINDOW; wc.lpszClassName = L"WindowClass1"; // register the window class RegisterClassEx(&wc); // create the window and use the result as the handle hWnd = CreateWindowEx(NULL, L"WindowClass1", // name of the window class L"Our First Windowed Program", // title of the window WS_OVERLAPPEDWINDOW, // window style 300, // x-position of the window 300, // y-position of the window 640, // width of the window 480, // height of the window NULL, // we have no parent window, NULL NULL, // we aren't using menus, NULL hInstance, // application handle NULL); // used with multiple windows, NULL // display the window on the screen ShowWindow(hWnd, nCmdShow); // enter the main loop: // this struct holds Windows event messages MSG msg; bool finished = InitDirect3D(hWnd); // Enter the infinite message loop while(TRUE) { // Check to see if any messages are waiting in the queue while(PeekMessage(&msg, NULL, 0, 0, PM_REMOVE)) { // Translate the message and dispatch it to WindowProc() TranslateMessage(&msg); DispatchMessage(&msg); } // If the message is WM_QUIT, exit the while loop if(msg.message == WM_QUIT) break; // Run game code here // ... // ... }; } // this is the main message handler for the program LRESULT CALLBACK WindowProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam) { // sort through and find what code to run for the message given switch(message) { // this message is read when the window is closed case WM_DESTROY: { // close the application entirely PostQuitMessage(0); return 0; } break; } // Handle any messages the switch statement didn't return DefWindowProc (hWnd, message, wParam, lParam); } bool InitDirect3D(HWND g_hWnd) { DXGI_SWAP_CHAIN_DESC sd; ZeroMemory( &sd, sizeof(sd) ); sd.BufferCount = 1; sd.BufferDesc.Width = 640; sd.BufferDesc.Height = 480; sd.BufferDesc.Format = DXGI_FORMAT_R8G8B8A8_UNORM; sd.BufferDesc.RefreshRate.Numerator = 60; sd.BufferDesc.RefreshRate.Denominator = 1; sd.BufferUsage = DXGI_USAGE_RENDER_TARGET_OUTPUT; sd.OutputWindow = g_hWnd; sd.SampleDesc.Count = 1; sd.SampleDesc.Quality = 0; sd.Windowed = TRUE; if( FAILED( D3D10CreateDeviceAndSwapChain( NULL, D3D10_DRIVER_TYPE_REFERENCE, NULL, 0, D3D10_SDK_VERSION, &sd, &g_pSwapChain, &g_pd3dDevice ) ) ) { return FALSE; } return TRUE; }

  Read the article

• OpenXML sdk Modify a sheet in my Excel document

  - by user465202

  hi! I create an empty template in excel. I would like to open the template and edit the document but I do not know how to change the existing sheet. That's the code: using (SpreadsheetDocument xl = SpreadsheetDocument.Open(filename, true)) { WorkbookPart wbp = xl.WorkbookPart; WorkbookPart workbook = xl.WorkbookPart; // Get the worksheet with the required name. // To be used to match the ID for the required sheet data // because the Sheet class and the SheetData class aren't // linked to each other directly. Sheet s = null; if (wbp.Workbook.Sheets.Elements().Count(nm = nm.Name == sheetName) == 0) { // no such sheet with that name xl.Close(); return; } else { s = (Sheet)wbp.Workbook.Sheets.Elements().Where(nm = nm.Name == sheetName).First(); } WorksheetPart wsp = (WorksheetPart)xl.WorkbookPart.GetPartById(s.Id.Value); Worksheet worksheet = new Worksheet(); SheetData sd = new SheetData(); //SheetData sd = (SheetData)wsp.Worksheet.GetFirstChild(); Stylesheet styleSheet = workbook.WorkbookStylesPart.Stylesheet; //SheetData sheetData = new SheetData(); //build the formatted header style UInt32Value headerFontIndex = util.CreateFont( styleSheet, "Arial", 10, true, System.Drawing.Color.Red); //build the formatted date style UInt32Value dateFontIndex = util.CreateFont( styleSheet, "Arial", 8, true, System.Drawing.Color.Black); //set the background color style UInt32Value headerFillIndex = util.CreateFill( styleSheet, System.Drawing.Color.Black); //create the cell style by combining font/background UInt32Value headerStyleIndex = util.CreateCellFormat( styleSheet, headerFontIndex, headerFillIndex, null); /* * Create a set of basic cell styles for specific formats... * If you are controlling your table then you can simply create the styles you need, * this set of code is still intended to be generic. */ _numberStyleId = util.CreateCellFormat(styleSheet, null, null, UInt32Value.FromUInt32(3)); _doubleStyleId = util.CreateCellFormat(styleSheet, null, null, UInt32Value.FromUInt32(4)); _dateStyleId = util.CreateCellFormat(styleSheet, null, null, UInt32Value.FromUInt32(14)); _textStyleId = util.CreateCellFormat(styleSheet, headerFontIndex, headerFillIndex, null); _percentageStyleId = util.CreateCellFormat(styleSheet, null, null, UInt32Value.FromUInt32(9)); util.AddNumber(xl, sheetName, (UInt32)3, "E", "27", _numberStyleId); util.AddNumber(xl, sheetName, (UInt32)3, "F", "3.6", _doubleStyleId); util.AddNumber(xl, sheetName, (UInt32)5, "L", "5", _percentageStyleId); util.AddText(xl, sheetName, (UInt32)5, "M", "Dario", _textStyleId); util.AddDate(xl, sheetName, (UInt32)3, "J", DateTime.Now, _dateStyleId); util.AddImage(xl, sheetName, imagePath, "Smile", "Smile", 30, 30); util.MergeCells(xl, sheetName, "D12", "F12"); //util.DeleteValueCell(spreadsheet, sheetName, "F", (UInt32)8); txtCellText.Text = util.GetCellValue(xl, sheetName, (UInt32)5, "M"); double number = util.GetCellDoubleValue(xl, sheetName, (UInt32)3, "E"); double numberD = util.GetCellDoubleValue(xl, sheetName, (UInt32)3, "F"); DateTime datee = util.GetCellDateTimeValue(xl, sheetName, (UInt32)3, "J"); //txtDoubleCell.Text = util.GetCellValue(spreadsheet, sheetName, (UInt32)3, "P"); txtPercentualeCell.Text = util.GetCellValue(xl, sheetName, (UInt32)5, "L"); string date = util.GetCellValue(xl, sheetName, (UInt32)3, "J"); double dateD = Convert.ToDouble(date); DateTime dateTime = DateTime.FromOADate(dateD); txtDateCell.Text = dateTime.ToShortDateString(); //worksheet.Append(sd); /* Columns columns = new Columns(); columns.Append(util.CreateColumnData(10, 10, 40)); worksheet.Append(columns); */ SheetProtection sheetProtection1 = new SheetProtection() { Sheet = true, Objects = true, Scenarios = true, SelectLockedCells = true, SelectUnlockedCells = true }; worksheet.Append(sheetProtection1); wsp.Worksheet = worksheet; wsp.Worksheet.Save(); xl.WorkbookPart.Workbook.Save(); xl.Close(); thanks!

  Read the article

• How to make a jQuery plugin (the right way)?

  - by macek

  I know there are jQuery cookie plugins out there, but I wanted to write one for the sake of better learning the jQuery plugin pattern. I like the separation of "work" in small, manageable functions, but I feel like I'm passing name, value, and options arguments around too much. Is there a way this can be refactored? I'm looking for snippets of code to help illustrate examples provided with in answers. Any help is appreciated. Thanks :) example usage $.cookie('foo', 'bar', {expires:7}); $.cookie('foo'); //=> bar $.cookie('foo', null); $.cookie('foo'); //=> undefined Edit: I did a little bit of work on this. You can view the revision history to see where this has come from. It still feels like more refactoring can be done to optimize the flow a bit. Any ideas? the plugin (function($){ $.cookie = function(name, value, options) { if (typeof value == 'undefined') { return get(name); } else { options = $.extend({}, $.cookie.defaults, options || {}); return (value != null) ? set(name, value, options) : unset(name, options); } }; $.cookie.defaults = { expires: null, path: '/', domain: null, secure: false }; var set = function(name, value, options){ console.log(options); return document.cookie = options_string(name, value, options); }; var get = function(name){ var cookies = {}; $.map(document.cookie.split(';'), function(pair){ var c = $.trim(pair).split('='); cookies[c[0]] = c[1]; }); return decodeURIComponent(cookies[name]); }; var unset = function(name, options){ value = ''; options.expires = -1; set(name, value, options); }; var options_string = function(name, value, options){ var pairs = [param.name(name, value)]; $.each(options, function(k,v){ pairs.push(param[k](v)); }); return $.map(pairs, function(p){ return p === null ? null : p; }).join(';'); }; var param = { name: function(name, value){ return name + "=" + encodeURIComponent(value); }, expires: function(value){ // no expiry if(value === null){ return null; } // number of days else if(typeof value == "number"){ d = new Date(); d.setTime(d.getTime() + (value * 24 * 60 * 60 * 1000)); } // date object else if(typeof value == "object" && value instanceof "Date") { d = value; } return "expires=" + d.toUTCString(); }, path: function(value){ return "path="+value; }, domain: function(value){ return value === null ? null : "domain=" + value; }, secure: function(bool){ return bool ? "secure" : null; } }; })(jQuery);

  Read the article

• Problems with createImage(int width, int height)

  - by Jonathan

  I have the following code, which is run every 10ms as part of a game: private void gameRender() { if(dbImage == null) { //createImage() returns null if GraphicsEnvironment.isHeadless() //returns true. (java.awt.GraphicsEnvironment) dbImage = createImage(PWIDTH, PHEIGHT); if(dbImage == null) { System.out.println("dbImage is null"); //Error recieved return; } else dbg = dbImage.getGraphics(); } //clear the background dbg.setColor(Color.white); dbg.fillRect(0, 0, PWIDTH, PHEIGHT); //draw game elements... if(gameOver) { gameOverMessage(dbg); } } The problem is that it enters the if statement which checks for the Image being null, even after I attempt to define the image. I looked around, and it seems that createImage() will return null if GraphicsEnvironment.isHeadless() returns true. I don't understand exactly what the isHeadless() method's purpose is, but I thought it might have something to do with the compiler or IDE, so I tried on two, both of which get the same error (Eclipse, and BlueJ). Anyone have any idea what the source of the error is, and how I might fix it? Thanks in advance Jonathan ................................................................... EDIT: I am using java.awt.Component.createImage(int width, int height). The purpose of this method is to ensure the creation of, and edit an Image that will contain the view of the player of the game, that will later be drawn to the screen by means of a JPanel. Here is some more code if this helps at all: public class Sim2D extends JPanel implements Runnable { private static final int PWIDTH = 500; private static final int PHEIGHT = 400; private volatile boolean running = true; private volatile boolean gameOver = false; private Thread animator; //gameRender() private Graphics dbg; private Image dbImage = null; public Sim2D() { setBackground(Color.white); setPreferredSize(new Dimension(PWIDTH, PHEIGHT)); setFocusable(true); requestFocus(); //Sim2D now recieves key events readyForTermination(); addMouseListener( new MouseAdapter() { public void mousePressed(MouseEvent e) { testPress(e.getX(), e.getY()); } }); } //end of constructor private void testPress(int x, int y) { if(!gameOver) { gameOver = true; //end game at mousepress } } //end of testPress() private void readyForTermination() { addKeyListener( new KeyAdapter() { public void keyPressed(KeyEvent e) { int keyCode = e.getKeyCode(); if((keyCode == KeyEvent.VK_ESCAPE) || (keyCode == KeyEvent.VK_Q) || (keyCode == KeyEvent.VK_END) || ((keyCode == KeyEvent.VK_C) && e.isControlDown()) ) { running = false; //end process on above list of keypresses } } }); } //end of readyForTermination() public void addNotify() { super.addNotify(); //creates the peer startGame(); //start the thread } //end of addNotify() public void startGame() { if(animator == null || !running) { animator = new Thread(this); animator.start(); } } //end of startGame() //run method for world public void run() { while(running) { long beforeTime, timeDiff, sleepTime; beforeTime = System.nanoTime(); gameUpdate(); //updates objects in game (step event in game) gameRender(); //renders image paintScreen(); //paints rendered image to screen timeDiff = (System.nanoTime() - beforeTime) / 1000000; sleepTime = 10 - timeDiff; if(sleepTime <= 0) //if took longer than 10ms { sleepTime = 5; //sleep a bit anyways } try{ Thread.sleep(sleepTime); //sleep by allotted time (attempts to keep this loop to about 10ms) } catch(InterruptedException ex){} beforeTime = System.nanoTime(); } System.exit(0); } //end of run() private void gameRender() { if(dbImage == null) { dbImage = createImage(PWIDTH, PHEIGHT); if(dbImage == null) { System.out.println("dbImage is null"); return; } else dbg = dbImage.getGraphics(); } //clear the background dbg.setColor(Color.white); dbg.fillRect(0, 0, PWIDTH, PHEIGHT); //draw game elements... if(gameOver) { gameOverMessage(dbg); } } //end of gameRender() } //end of class Sim2D Hope this helps clear things up a bit, Jonathan

  Read the article

• Read XML Files using LINQ to XML and Extension Methods

  - by psheriff

  In previous blog posts I have discussed how to use XML files to store data in your applications. I showed you how to read those XML files from your project and get XML from a WCF service. One of the problems with reading XML files is when elements or attributes are missing. If you try to read that missing data, then a null value is returned. This can cause a problem if you are trying to load that data into an object and a null is read. This blog post will show you how to create extension methods to detect null values and return valid values to load into your object. The XML Data An XML data file called Product.xml is located in the \Xml folder of the Silverlight sample project for this blog post. This XML file contains several rows of product data that will be used in each of the samples for this post. Each row has 4 attributes; namely ProductId, ProductName, IntroductionDate and Price. <Products>  <Product ProductId="1"           ProductName="Haystack Code Generator for .NET"           IntroductionDate="07/01/2010"  Price="799" />  <Product ProductId="2"           ProductName="ASP.Net Jumpstart Samples"           IntroductionDate="05/24/2005"  Price="0" />  ...  ...</Products> The Product Class Just as you create an Entity class to map each column in a table to a property in a class, you should do the same for an XML file too. In this case you will create a Product class with properties for each of the attributes in each element of product data. The following code listing shows the Product class. public class Product : CommonBase{  public const string XmlFile = @"Xml/Product.xml";   private string _ProductName;  private int _ProductId;  private DateTime _IntroductionDate;  private decimal _Price;   public string ProductName  {    get { return _ProductName; }    set {      if (_ProductName != value) {        _ProductName = value;        RaisePropertyChanged("ProductName");      }    }  }   public int ProductId  {    get { return _ProductId; }    set {      if (_ProductId != value) {        _ProductId = value;        RaisePropertyChanged("ProductId");      }    }  }   public DateTime IntroductionDate  {    get { return _IntroductionDate; }    set {      if (_IntroductionDate != value) {        _IntroductionDate = value;        RaisePropertyChanged("IntroductionDate");      }    }  }   public decimal Price  {    get { return _Price; }    set {      if (_Price != value) {        _Price = value;        RaisePropertyChanged("Price");      }    }  }} NOTE: The CommonBase class that the Product class inherits from simply implements the INotifyPropertyChanged event in order to inform your XAML UI of any property changes. You can see this class in the sample you download for this blog post. Reading Data When using LINQ to XML you call the Load method of the XElement class to load the XML file. Once the XML file has been loaded, you write a LINQ query to iterate over the “Product” Descendants in the XML file. The “select” portion of the LINQ query creates a new Product object for each row in the XML file. You retrieve each attribute by passing each attribute name to the Attribute() method and retrieving the data from the “Value” property. The Value property will return a null if there is no data, or will return the string value of the attribute. The Convert class is used to convert the value retrieved into the appropriate data type required by the Product class. private void LoadProducts(){  XElement xElem = null;   try  {    xElem = XElement.Load(Product.XmlFile);     // The following will NOT work if you have missing attributes    var products =         from elem in xElem.Descendants("Product")        orderby elem.Attribute("ProductName").Value        select new Product        {          ProductId = Convert.ToInt32(            elem.Attribute("ProductId").Value),          ProductName = Convert.ToString(            elem.Attribute("ProductName").Value),          IntroductionDate = Convert.ToDateTime(            elem.Attribute("IntroductionDate").Value),          Price = Convert.ToDecimal(elem.Attribute("Price").Value)        };     lstData.DataContext = products;  }  catch (Exception ex)  {    MessageBox.Show(ex.Message);  }} This is where the problem comes in. If you have any missing attributes in any of the rows in the XML file, or if the data in the ProductId or IntroductionDate is not of the appropriate type, then this code will fail! The reason? There is no built-in check to ensure that the correct type of data is contained in the XML file. This is where extension methods can come in real handy. Using Extension Methods Instead of using the Convert class to perform type conversions as you just saw, create a set of extension methods attached to the XAttribute class. These extension methods will perform null-checking and ensure that a valid value is passed back instead of an exception being thrown if there is invalid data in your XML file. private void LoadProducts(){  var xElem = XElement.Load(Product.XmlFile);   var products =       from elem in xElem.Descendants("Product")      orderby elem.Attribute("ProductName").Value      select new Product      {        ProductId = elem.Attribute("ProductId").GetAsInteger(),        ProductName = elem.Attribute("ProductName").GetAsString(),        IntroductionDate =            elem.Attribute("IntroductionDate").GetAsDateTime(),        Price = elem.Attribute("Price").GetAsDecimal()      };   lstData.DataContext = products;} Writing Extension Methods To create an extension method you will create a class with any name you like. In the code listing below is a class named XmlExtensionMethods. This listing just shows a couple of the available methods such as GetAsString and GetAsInteger. These methods are just like any other method you would write except when you pass in the parameter you prefix the type with the keyword “this”. This lets the compiler know that it should add this method to the class specified in the parameter. public static class XmlExtensionMethods{  public static string GetAsString(this XAttribute attr)  {    string ret = string.Empty;     if (attr != null && !string.IsNullOrEmpty(attr.Value))    {      ret = attr.Value;    }     return ret;  }   public static int GetAsInteger(this XAttribute attr)  {    int ret = 0;    int value = 0;     if (attr != null && !string.IsNullOrEmpty(attr.Value))    {      if(int.TryParse(attr.Value, out value))        ret = value;    }     return ret;  }   ...  ...} Each of the methods in the XmlExtensionMethods class should inspect the XAttribute to ensure it is not null and that the value in the attribute is not null. If the value is null, then a default value will be returned such as an empty string or a 0 for a numeric value. Summary Extension methods are a great way to simplify your code and provide protection to ensure problems do not occur when reading data. You will probably want to create more extension methods to handle XElement objects as well for when you use element-based XML. Feel free to extend these extension methods to accept a parameter which would be the default value if a null value is detected, or any other parameters you wish. NOTE: You can download the complete sample code at my website. http://www.pdsa.com/downloads. Choose “Tips & Tricks”, then "Read XML Files using LINQ to XML and Extension Methods" from the drop-down. Good Luck with your Coding,Paul D. Sheriff  

  Read the article

• Seeking on a Heap, and Two Useful DMVs

  - by Paul White

  So far in this mini-series on seeks and scans, we have seen that a simple ‘seek’ operation can be much more complex than it first appears.  A seek can contain one or more seek predicates – each of which can either identify at most one row in a unique index (a singleton lookup) or a range of values (a range scan).  When looking at a query plan, we will often need to look at the details of the seek operator in the Properties window to see how many operations it is performing, and what type of operation each one is.  As you saw in the first post in this series, the number of hidden seeking operations can have an appreciable impact on performance. Measuring Seeks and Scans I mentioned in my last post that there is no way to tell from a graphical query plan whether you are seeing a singleton lookup or a range scan.  You can work it out – if you happen to know that the index is defined as unique and the seek predicate is an equality comparison, but there’s no separate property that says ‘singleton lookup’ or ‘range scan’.  This is a shame, and if I had my way, the query plan would show different icons for range scans and singleton lookups – perhaps also indicating whether the operation was one or more of those operations underneath the covers. In light of all that, you might be wondering if there is another way to measure how many seeks of either type are occurring in your system, or for a particular query.  As is often the case, the answer is yes – we can use a couple of dynamic management views (DMVs): sys.dm_db_index_usage_stats and sys.dm_db_index_operational_stats. Index Usage Stats The index usage stats DMV contains counts of index operations from the perspective of the Query Executor (QE) – the SQL Server component that is responsible for executing the query plan.  It has three columns that are of particular interest to us: user_seeks – the number of times an Index Seek operator appears in an executed plan user_scans – the number of times a Table Scan or Index Scan operator appears in an executed plan user_lookups – the number of times an RID or Key Lookup operator appears in an executed plan An operator is counted once per execution (generating an estimated plan does not affect the totals), so an Index Seek that executes 10,000 times in a single plan execution adds 1 to the count of user seeks.  Even less intuitively, an operator is also counted once per execution even if it is not executed at all.  I will show you a demonstration of each of these things later in this post. Index Operational Stats The index operational stats DMV contains counts of index and table operations from the perspective of the Storage Engine (SE).  It contains a wealth of interesting information, but the two columns of interest to us right now are: range_scan_count – the number of range scans (including unrestricted full scans) on a heap or index structure singleton_lookup_count – the number of singleton lookups in a heap or index structure This DMV counts each SE operation, so 10,000 singleton lookups will add 10,000 to the singleton lookup count column, and a table scan that is executed 5 times will add 5 to the range scan count. The Test Rig To explore the behaviour of seeks and scans in detail, we will need to create a test environment.  The scripts presented here are best run on SQL Server 2008 Developer Edition, but the majority of the tests will work just fine on SQL Server 2005.  A couple of tests use partitioning, but these will be skipped if you are not running an Enterprise-equivalent SKU.  Ok, first up we need a database: USE master; GO IF DB_ID('ScansAndSeeks') IS NOT NULL DROP DATABASE ScansAndSeeks; GO CREATE DATABASE ScansAndSeeks; GO USE ScansAndSeeks; GO ALTER DATABASE ScansAndSeeks SET ALLOW_SNAPSHOT_ISOLATION OFF ; ALTER DATABASE ScansAndSeeks SET AUTO_CLOSE OFF, AUTO_SHRINK OFF, AUTO_CREATE_STATISTICS OFF, AUTO_UPDATE_STATISTICS OFF, PARAMETERIZATION SIMPLE, READ_COMMITTED_SNAPSHOT OFF, RESTRICTED_USER ; Notice that several database options are set in particular ways to ensure we get meaningful and reproducible results from the DMVs.  In particular, the options to auto-create and update statistics are disabled.  There are also three stored procedures, the first of which creates a test table (which may or may not be partitioned).  The table is pretty much the same one we used yesterday: The table has 100 rows, and both the key_col and data columns contain the same values – the integers from 1 to 100 inclusive.  The table is a heap, with a non-clustered primary key on key_col, and a non-clustered non-unique index on the data column.  The only reason I have used a heap here, rather than a clustered table, is so I can demonstrate a seek on a heap later on.  The table has an extra column (not shown because I am too lazy to update the diagram from yesterday) called padding – a CHAR(100) column that just contains 100 spaces in every row.  It’s just there to discourage SQL Server from choosing table scan over an index + RID lookup in one of the tests. The first stored procedure is called ResetTest: CREATE PROCEDURE dbo.ResetTest @Partitioned BIT = 'false' AS BEGIN SET NOCOUNT ON ; IF OBJECT_ID(N'dbo.Example', N'U') IS NOT NULL BEGIN DROP TABLE dbo.Example; END ; -- Test table is a heap -- Non-clustered primary key on 'key_col' CREATE TABLE dbo.Example ( key_col INTEGER NOT NULL, data INTEGER NOT NULL, padding CHAR(100) NOT NULL DEFAULT SPACE(100), CONSTRAINT [PK dbo.Example key_col] PRIMARY KEY NONCLUSTERED (key_col) ) ; IF @Partitioned = 'true' BEGIN -- Enterprise, Trial, or Developer -- required for partitioning tests IF SERVERPROPERTY('EngineEdition') = 3 BEGIN EXECUTE (' DROP TABLE dbo.Example ; IF EXISTS ( SELECT 1 FROM sys.partition_schemes WHERE name = N''PS'' ) DROP PARTITION SCHEME PS ; IF EXISTS ( SELECT 1 FROM sys.partition_functions WHERE name = N''PF'' ) DROP PARTITION FUNCTION PF ; CREATE PARTITION FUNCTION PF (INTEGER) AS RANGE RIGHT FOR VALUES (20, 40, 60, 80, 100) ; CREATE PARTITION SCHEME PS AS PARTITION PF ALL TO ([PRIMARY]) ; CREATE TABLE dbo.Example ( key_col INTEGER NOT NULL, data INTEGER NOT NULL, padding CHAR(100) NOT NULL DEFAULT SPACE(100), CONSTRAINT [PK dbo.Example key_col] PRIMARY KEY NONCLUSTERED (key_col) ) ON PS (key_col); '); END ELSE BEGIN RAISERROR('Invalid SKU for partition test', 16, 1); RETURN; END; END ; -- Non-unique non-clustered index on the 'data' column CREATE NONCLUSTERED INDEX [IX dbo.Example data] ON dbo.Example (data) ; -- Add 100 rows INSERT dbo.Example WITH (TABLOCKX) ( key_col, data ) SELECT key_col = V.number, data = V.number FROM master.dbo.spt_values AS V WHERE V.[type] = N'P' AND V.number BETWEEN 1 AND 100 ; END; GO The second stored procedure, ShowStats, displays information from the Index Usage Stats and Index Operational Stats DMVs: CREATE PROCEDURE dbo.ShowStats @Partitioned BIT = 'false' AS BEGIN -- Index Usage Stats DMV (QE) SELECT index_name = ISNULL(I.name, I.type_desc), scans = IUS.user_scans, seeks = IUS.user_seeks, lookups = IUS.user_lookups FROM sys.dm_db_index_usage_stats AS IUS JOIN sys.indexes AS I ON I.object_id = IUS.object_id AND I.index_id = IUS.index_id WHERE IUS.database_id = DB_ID(N'ScansAndSeeks') AND IUS.object_id = OBJECT_ID(N'dbo.Example', N'U') ORDER BY I.index_id ; -- Index Operational Stats DMV (SE) IF @Partitioned = 'true' SELECT index_name = ISNULL(I.name, I.type_desc), partitions = COUNT(IOS.partition_number), range_scans = SUM(IOS.range_scan_count), single_lookups = SUM(IOS.singleton_lookup_count) FROM sys.dm_db_index_operational_stats ( DB_ID(N'ScansAndSeeks'), OBJECT_ID(N'dbo.Example', N'U'), NULL, NULL ) AS IOS JOIN sys.indexes AS I ON I.object_id = IOS.object_id AND I.index_id = IOS.index_id GROUP BY I.index_id, -- Key I.name, I.type_desc ORDER BY I.index_id; ELSE SELECT index_name = ISNULL(I.name, I.type_desc), range_scans = SUM(IOS.range_scan_count), single_lookups = SUM(IOS.singleton_lookup_count) FROM sys.dm_db_index_operational_stats ( DB_ID(N'ScansAndSeeks'), OBJECT_ID(N'dbo.Example', N'U'), NULL, NULL ) AS IOS JOIN sys.indexes AS I ON I.object_id = IOS.object_id AND I.index_id = IOS.index_id GROUP BY I.index_id, -- Key I.name, I.type_desc ORDER BY I.index_id; END; The final stored procedure, RunTest, executes a query written against the example table: CREATE PROCEDURE dbo.RunTest @SQL VARCHAR(8000), @Partitioned BIT = 'false' AS BEGIN -- No execution plan yet SET STATISTICS XML OFF ; -- Reset the test environment EXECUTE dbo.ResetTest @Partitioned ; -- Previous call will throw an error if a partitioned -- test was requested, but SKU does not support it IF @@ERROR = 0 BEGIN -- IO statistics and plan on SET STATISTICS XML, IO ON ; -- Test statement EXECUTE (@SQL) ; -- Plan and IO statistics off SET STATISTICS XML, IO OFF ; EXECUTE dbo.ShowStats @Partitioned; END; END; The Tests The first test is a simple scan of the heap table: EXECUTE dbo.RunTest @SQL = 'SELECT * FROM Example'; The top result set comes from the Index Usage Stats DMV, so it is the Query Executor’s (QE) view.  The lower result is from Index Operational Stats, which shows statistics derived from the actions taken by the Storage Engine (SE).  We see that QE performed 1 scan operation on the heap, and SE performed a single range scan.  Let’s try a single-value equality seek on a unique index next: EXECUTE dbo.RunTest @SQL = 'SELECT key_col FROM Example WHERE key_col = 32'; This time we see a single seek on the non-clustered primary key from QE, and one singleton lookup on the same index by the SE.  Now for a single-value seek on the non-unique non-clustered index: EXECUTE dbo.RunTest @SQL = 'SELECT data FROM Example WHERE data = 32'; QE shows a single seek on the non-clustered non-unique index, but SE shows a single range scan on that index – not the singleton lookup we saw in the previous test.  That makes sense because we know that only a single-value seek into a unique index is a singleton seek.  A single-value seek into a non-unique index might retrieve any number of rows, if you think about it.  The next query is equivalent to the IN list example seen in the first post in this series, but it is written using OR (just for variety, you understand): EXECUTE dbo.RunTest @SQL = 'SELECT data FROM Example WHERE data = 32 OR data = 33'; The plan looks the same, and there’s no difference in the stats recorded by QE, but the SE shows two range scans.  Again, these are range scans because we are looking for two values in the data column, which is covered by a non-unique index.  I’ve added a snippet from the Properties window to show that the query plan does show two seek predicates, not just one.  Now let’s rewrite the query using BETWEEN: EXECUTE dbo.RunTest @SQL = 'SELECT data FROM Example WHERE data BETWEEN 32 AND 33'; Notice the seek operator only has one predicate now – it’s just a single range scan from 32 to 33 in the index – as the SE output shows.  For the next test, we will look up four values in the key_col column: EXECUTE dbo.RunTest @SQL = 'SELECT key_col FROM Example WHERE key_col IN (2,4,6,8)'; Just a single seek on the PK from the Query Executor, but four singleton lookups reported by the Storage Engine – and four seek predicates in the Properties window.  On to a more complex example: EXECUTE dbo.RunTest @SQL = 'SELECT * FROM Example WITH (INDEX([PK dbo.Example key_col])) WHERE key_col BETWEEN 1 AND 8'; This time we are forcing use of the non-clustered primary key to return eight rows.  The index is not covering for this query, so the query plan includes an RID lookup into the heap to fetch the data and padding columns.  The QE reports a seek on the PK and a lookup on the heap.  The SE reports a single range scan on the PK (to find key_col values between 1 and 8), and eight singleton lookups on the heap.  Remember that a bookmark lookup (RID or Key) is a seek to a single value in a ‘unique index’ – it finds a row in the heap or cluster from a unique RID or clustering key – so that’s why lookups are always singleton lookups, not range scans. Our next example shows what happens when a query plan operator is not executed at all: EXECUTE dbo.RunTest @SQL = 'SELECT key_col FROM Example WHERE key_col = 8 AND @@TRANCOUNT < 0'; The Filter has a start-up predicate which is always false (if your @@TRANCOUNT is less than zero, call CSS immediately).  The index seek is never executed, but QE still records a single seek against the PK because the operator appears once in an executed plan.  The SE output shows no activity at all.  This next example is 2008 and above only, I’m afraid: EXECUTE dbo.RunTest @SQL = 'SELECT * FROM Example WHERE key_col BETWEEN 1 AND 30', @Partitioned = 'true'; This is the first example to use a partitioned table.  QE reports a single seek on the heap (yes – a seek on a heap), and the SE reports two range scans on the heap.  SQL Server knows (from the partitioning definition) that it only needs to look at partitions 1 and 2 to find all the rows where key_col is between 1 and 30 – the engine seeks to find the two partitions, and performs a range scan seek on each partition. The final example for today is another seek on a heap – try to work out the output of the query before running it! EXECUTE dbo.RunTest @SQL = 'SELECT TOP (2) WITH TIES * FROM Example WHERE key_col BETWEEN 1 AND 50 ORDER BY $PARTITION.PF(key_col) DESC', @Partitioned = 'true'; Notice the lack of an explicit Sort operator in the query plan to enforce the ORDER BY clause, and the backward range scan. © 2011 Paul White email: [email protected] twitter: @SQL_Kiwi

  Read the article

• Adding SQL Cache Dependencies to the Loosely coupled .NET Cache Provider

  - by Rhames

  This post adds SQL Cache Dependency support to the loosely coupled .NET Cache Provider that I described in the previous post (http://geekswithblogs.net/Rhames/archive/2012/09/11/loosely-coupled-.net-cache-provider-using-dependency-injection.aspx). The sample code is available on github at https://github.com/RobinHames/CacheProvider.git. Each time we want to apply a cache dependency to a call to fetch or cache a data item we need to supply an instance of the relevant dependency implementation. This suggests an Abstract Factory will be useful to create cache dependencies as needed. We can then use Dependency Injection to inject the factory into the relevant consumer. Castle Windsor provides a typed factory facility that will be utilised to implement the cache dependency abstract factory (see http://docs.castleproject.org/Windsor.Typed-Factory-Facility-interface-based-factories.ashx). Cache Dependency Interfaces First I created a set of cache dependency interfaces in the domain layer, which can be used to pass a cache dependency into the cache provider. ICacheDependency The ICacheDependency interface is simply an empty interface that is used as a parent for the specific cache dependency interfaces. This will allow us to place a generic constraint on the Cache Dependency Factory, and will give us a type that can be passed into the relevant Cache Provider methods. namespace CacheDiSample.Domain.CacheInterfaces { public interface ICacheDependency { } }   ISqlCacheDependency.cs The ISqlCacheDependency interface provides specific SQL caching details, such as a Sql Command or a database connection and table. It is the concrete implementation of this interface that will be created by the factory in passed into the Cache Provider. using System; using System.Collections.Generic; using System.Linq; using System.Text;   namespace CacheDiSample.Domain.CacheInterfaces { public interface ISqlCacheDependency : ICacheDependency { ISqlCacheDependency Initialise(string databaseConnectionName, string tableName); ISqlCacheDependency Initialise(System.Data.SqlClient.SqlCommand sqlCommand); } } If we want other types of cache dependencies, such as by key or file, interfaces may be created to support these (the sample code includes an IKeyCacheDependency interface). Modifying ICacheProvider to accept Cache Dependencies Next I modified the exisitng ICacheProvider<T> interface so that cache dependencies may be passed into a Fetch method call. I did this by adding two overloads to the existing Fetch methods, which take an IEnumerable<ICacheDependency> parameter (the IEnumerable allows more than one cache dependency to be included). I also added a method to create cache dependencies. This means that the implementation of the Cache Provider will require a dependency on the Cache Dependency Factory. It is pretty much down to personal choice as to whether this approach is taken, or whether the Cache Dependency Factory is injected directly into the repository or other consumer of Cache Provider. I think, because the cache dependency cannot be used without the Cache Provider, placing the dependency on the factory into the Cache Provider implementation is cleaner. ICacheProvider.cs using System; using System.Collections.Generic;   namespace CacheDiSample.Domain.CacheInterfaces { public interface ICacheProvider<T> { T Fetch(string key, Func<T> retrieveData, DateTime? absoluteExpiry, TimeSpan? relativeExpiry); T Fetch(string key, Func<T> retrieveData, DateTime? absoluteExpiry, TimeSpan? relativeExpiry, IEnumerable<ICacheDependency> cacheDependencies);   IEnumerable<T> Fetch(string key, Func<IEnumerable<T>> retrieveData, DateTime? absoluteExpiry, TimeSpan? relativeExpiry); IEnumerable<T> Fetch(string key, Func<IEnumerable<T>> retrieveData, DateTime? absoluteExpiry, TimeSpan? relativeExpiry, IEnumerable<ICacheDependency> cacheDependencies);   U CreateCacheDependency<U>() where U : ICacheDependency; } }   Cache Dependency Factory Next I created the interface for the Cache Dependency Factory in the domain layer. ICacheDependencyFactory.cs namespace CacheDiSample.Domain.CacheInterfaces { public interface ICacheDependencyFactory { T Create<T>() where T : ICacheDependency;   void Release<T>(T cacheDependency) where T : ICacheDependency; } }   I used the ICacheDependency parent interface as a generic constraint on the create and release methods in the factory interface. Now the interfaces are in place, I moved on to the concrete implementations. ISqlCacheDependency Concrete Implementation The concrete implementation of ISqlCacheDependency will need to provide an instance of System.Web.Caching.SqlCacheDependency to the Cache Provider implementation. Unfortunately this class is sealed, so I cannot simply inherit from this. Instead, I created an interface called IAspNetCacheDependency that will provide a Create method to create an instance of the relevant System.Web.Caching Cache Dependency type. This interface is specific to the ASP.NET implementation of the Cache Provider, so it should be defined in the same layer as the concrete implementation of the Cache Provider (the MVC UI layer in the sample code). IAspNetCacheDependency.cs using System.Web.Caching;   namespace CacheDiSample.CacheProviders { public interface IAspNetCacheDependency { CacheDependency CreateAspNetCacheDependency(); } }   Next, I created the concrete implementation of the ISqlCacheDependency interface. This class also implements the IAspNetCacheDependency interface. This concrete implementation also is defined in the same layer as the Cache Provider implementation. AspNetSqlCacheDependency.cs using System.Web.Caching; using CacheDiSample.Domain.CacheInterfaces;   namespace CacheDiSample.CacheProviders { public class AspNetSqlCacheDependency : ISqlCacheDependency, IAspNetCacheDependency { private string databaseConnectionName;   private string tableName;   private System.Data.SqlClient.SqlCommand sqlCommand;   #region ISqlCacheDependency Members   public ISqlCacheDependency Initialise(string databaseConnectionName, string tableName) { this.databaseConnectionName = databaseConnectionName; this.tableName = tableName; return this; }   public ISqlCacheDependency Initialise(System.Data.SqlClient.SqlCommand sqlCommand) { this.sqlCommand = sqlCommand; return this; }   #endregion   #region IAspNetCacheDependency Members   public System.Web.Caching.CacheDependency CreateAspNetCacheDependency() { if (sqlCommand != null) return new SqlCacheDependency(sqlCommand); else return new SqlCacheDependency(databaseConnectionName, tableName); }   #endregion   } }   ICacheProvider Concrete Implementation The ICacheProvider interface is implemented by the CacheProvider class. This implementation is modified to include the changes to the ICacheProvider interface. First I needed to inject the Cache Dependency Factory into the Cache Provider: private ICacheDependencyFactory cacheDependencyFactory;   public CacheProvider(ICacheDependencyFactory cacheDependencyFactory) { if (cacheDependencyFactory == null) throw new ArgumentNullException("cacheDependencyFactory");   this.cacheDependencyFactory = cacheDependencyFactory; }   Next I implemented the CreateCacheDependency method, which simply passes on the create request to the factory: public U CreateCacheDependency<U>() where U : ICacheDependency { return this.cacheDependencyFactory.Create<U>(); }   The signature of the FetchAndCache helper method was modified to take an additional IEnumerable<ICacheDependency> parameter:   private U FetchAndCache<U>(string key, Func<U> retrieveData, DateTime? absoluteExpiry, TimeSpan? relativeExpiry, IEnumerable<ICacheDependency> cacheDependencies) and the following code added to create the relevant System.Web.Caching.CacheDependency object for any dependencies and pass them to the HttpContext Cache: CacheDependency aspNetCacheDependencies = null;   if (cacheDependencies != null) { if (cacheDependencies.Count() == 1) // We know that the implementations of ICacheDependency will also implement IAspNetCacheDependency // so we can use a cast here and call the CreateAspNetCacheDependency() method aspNetCacheDependencies = ((IAspNetCacheDependency)cacheDependencies.ElementAt(0)).CreateAspNetCacheDependency(); else if (cacheDependencies.Count() > 1) { AggregateCacheDependency aggregateCacheDependency = new AggregateCacheDependency(); foreach (ICacheDependency cacheDependency in cacheDependencies) { // We know that the implementations of ICacheDependency will also implement IAspNetCacheDependency // so we can use a cast here and call the CreateAspNetCacheDependency() method aggregateCacheDependency.Add(((IAspNetCacheDependency)cacheDependency).CreateAspNetCacheDependency()); } aspNetCacheDependencies = aggregateCacheDependency; } }   HttpContext.Current.Cache.Insert(key, value, aspNetCacheDependencies, absoluteExpiry.Value, relativeExpiry.Value);   The full code listing for the modified CacheProvider class is shown below: using System; using System.Collections.Generic; using System.Linq; using System.Web; using System.Web.Caching; using CacheDiSample.Domain.CacheInterfaces;   namespace CacheDiSample.CacheProviders { public class CacheProvider<T> : ICacheProvider<T> { private ICacheDependencyFactory cacheDependencyFactory;   public CacheProvider(ICacheDependencyFactory cacheDependencyFactory) { if (cacheDependencyFactory == null) throw new ArgumentNullException("cacheDependencyFactory");   this.cacheDependencyFactory = cacheDependencyFactory; }   public T Fetch(string key, Func<T> retrieveData, DateTime? absoluteExpiry, TimeSpan? relativeExpiry) { return FetchAndCache<T>(key, retrieveData, absoluteExpiry, relativeExpiry, null); }   public T Fetch(string key, Func<T> retrieveData, DateTime? absoluteExpiry, TimeSpan? relativeExpiry, IEnumerable<ICacheDependency> cacheDependencies) { return FetchAndCache<T>(key, retrieveData, absoluteExpiry, relativeExpiry, cacheDependencies); }   public IEnumerable<T> Fetch(string key, Func<IEnumerable<T>> retrieveData, DateTime? absoluteExpiry, TimeSpan? relativeExpiry) { return FetchAndCache<IEnumerable<T>>(key, retrieveData, absoluteExpiry, relativeExpiry, null); }   public IEnumerable<T> Fetch(string key, Func<IEnumerable<T>> retrieveData, DateTime? absoluteExpiry, TimeSpan? relativeExpiry, IEnumerable<ICacheDependency> cacheDependencies) { return FetchAndCache<IEnumerable<T>>(key, retrieveData, absoluteExpiry, relativeExpiry, cacheDependencies); }   public U CreateCacheDependency<U>() where U : ICacheDependency { return this.cacheDependencyFactory.Create<U>(); }   #region Helper Methods   private U FetchAndCache<U>(string key, Func<U> retrieveData, DateTime? absoluteExpiry, TimeSpan? relativeExpiry, IEnumerable<ICacheDependency> cacheDependencies) { U value; if (!TryGetValue<U>(key, out value)) { value = retrieveData(); if (!absoluteExpiry.HasValue) absoluteExpiry = Cache.NoAbsoluteExpiration;   if (!relativeExpiry.HasValue) relativeExpiry = Cache.NoSlidingExpiration;   CacheDependency aspNetCacheDependencies = null;   if (cacheDependencies != null) { if (cacheDependencies.Count() == 1) // We know that the implementations of ICacheDependency will also implement IAspNetCacheDependency // so we can use a cast here and call the CreateAspNetCacheDependency() method aspNetCacheDependencies = ((IAspNetCacheDependency)cacheDependencies.ElementAt(0)).CreateAspNetCacheDependency(); else if (cacheDependencies.Count() > 1) { AggregateCacheDependency aggregateCacheDependency = new AggregateCacheDependency(); foreach (ICacheDependency cacheDependency in cacheDependencies) { // We know that the implementations of ICacheDependency will also implement IAspNetCacheDependency // so we can use a cast here and call the CreateAspNetCacheDependency() method aggregateCacheDependency.Add( ((IAspNetCacheDependency)cacheDependency).CreateAspNetCacheDependency()); } aspNetCacheDependencies = aggregateCacheDependency; } }   HttpContext.Current.Cache.Insert(key, value, aspNetCacheDependencies, absoluteExpiry.Value, relativeExpiry.Value);   } return value; }   private bool TryGetValue<U>(string key, out U value) { object cachedValue = HttpContext.Current.Cache.Get(key); if (cachedValue == null) { value = default(U); return false; } else { try { value = (U)cachedValue; return true; } catch { value = default(U); return false; } } }   #endregion } }   Wiring up the DI Container Now the implementations for the Cache Dependency are in place, I wired them up in the existing Windsor CacheInstaller. First I needed to register the implementation of the ISqlCacheDependency interface: container.Register( Component.For<ISqlCacheDependency>() .ImplementedBy<AspNetSqlCacheDependency>() .LifestyleTransient());   Next I registered the Cache Dependency Factory. Notice that I have not implemented the ICacheDependencyFactory interface. Castle Windsor will do this for me by using the Type Factory Facility. I do need to bring the Castle.Facilities.TypedFacility namespace into scope: using Castle.Facilities.TypedFactory;   Then I registered the factory: container.AddFacility<TypedFactoryFacility>();   container.Register( Component.For<ICacheDependencyFactory>() .AsFactory()); The full code for the CacheInstaller class is: using Castle.MicroKernel.Registration; using Castle.MicroKernel.SubSystems.Configuration; using Castle.Windsor; using Castle.Facilities.TypedFactory;   using CacheDiSample.Domain.CacheInterfaces; using CacheDiSample.CacheProviders;   namespace CacheDiSample.WindsorInstallers { public class CacheInstaller : IWindsorInstaller { public void Install(IWindsorContainer container, IConfigurationStore store) { container.Register( Component.For(typeof(ICacheProvider<>)) .ImplementedBy(typeof(CacheProvider<>)) .LifestyleTransient());   container.Register( Component.For<ISqlCacheDependency>() .ImplementedBy<AspNetSqlCacheDependency>() .LifestyleTransient());   container.AddFacility<TypedFactoryFacility>();   container.Register( Component.For<ICacheDependencyFactory>() .AsFactory()); } } }   Configuring the ASP.NET SQL Cache Dependency There are a couple of configuration steps required to enable SQL Cache Dependency for the application and database. From the Visual Studio Command Prompt, the following commands should be used to enable the Cache Polling of the relevant database tables: aspnet_regsql -S <servername> -E -d <databasename> –ed aspnet_regsql -S <servername> -E -d CacheSample –et –t <tablename>   (The –t option should be repeated for each table that is to be made available for cache dependencies). Finally the SQL Cache Polling needs to be enabled by adding the following configuration to the <system.web> section of web.config: <caching> <sqlCacheDependency pollTime="10000" enabled="true"> <databases> <add name="BloggingContext" connectionStringName="BloggingContext"/> </databases> </sqlCacheDependency> </caching>   (obviously the name and connection string name should be altered as required). Using a SQL Cache Dependency Now all the coding is complete. To specify a SQL Cache Dependency, I can modify my BlogRepositoryWithCaching decorator class (see the earlier post) as follows: public IList<Blog> GetAll() { var sqlCacheDependency = cacheProvider.CreateCacheDependency<ISqlCacheDependency>() .Initialise("BloggingContext", "Blogs");   ICacheDependency[] cacheDependencies = new ICacheDependency[] { sqlCacheDependency };   string key = string.Format("CacheDiSample.DataAccess.GetAll");   return cacheProvider.Fetch(key, () => { return parentBlogRepository.GetAll(); }, null, null, cacheDependencies) .ToList(); }   This will add a dependency of the “Blogs” table in the database. The data will remain in the cache until the contents of this table change, then the cache item will be invalidated, and the next call to the GetAll() repository method will be routed to the parent repository to refresh the data from the database.

  Read the article

• What is the best option for reading Java property files?

  - by Mr Morgan

  Hello I have an application which uses a servlet to read an intialization parameter from web.xml for the location of a property file. The serlvet then creates an instance of a class which stores the location of the file for other programs to read as required. This class has appropriate get and set methods. But my question concerns access to the properties: should the physical property file be read by each program as at runtime or should the properties be stored in memory instead? The properties are not currently altered at runtime but this could change? I've seen various alternative approaches but am not sure which is best. Thanks Mr Morgan

  Read the article

• Getting ClassCastException with JSF 1.2 Custom Component and BEA 10.3

  - by Tobi

  Im getting a ClassCastException if i use Attributes in my Custom Headline Tag. Without Attributes rendering works fine. Calling <t:headline value="test" /> gives a ClassCastException even before a Method in my HeadlineComponent or HeadlineTag-Class is called. <t:headline /> works fine. I'm using MyFaces-1.2, on BEA 10.3 default.jsp <%@ page language="java" contentType="text/html; charset=ISO-8859-1" pageEncoding="ISO-8859-1"%> <%@ taglib prefix="f" uri="http://java.sun.com/jsf/core"%> <%@ taglib prefix="h" uri="http://java.sun.com/jsf/html"%> <%@ taglib prefix="t" uri="http://www.tobi.de/taglibrary" %> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> <title>Tobi Test</title> </head> <body> <f:view> <t:headline value="test" /> </f:view> </body> </html> HeadlineComponent.java package tobi.web.component.headline; import java.io.IOException; import javax.el.ValueExpression; import javax.faces.component.UIOutput; import javax.faces.context.FacesContext; import javax.faces.context.ResponseWriter; public class HeadlineComponent extends UIOutput { private String value; private Integer size; @Override public Object saveState(FacesContext context) { Object values[] = new Object[3]; values[0] = super.saveState(context); values[1] = value; values[2] = size; return ((Object)(values)); } @Override public void restoreState(FacesContext context, Object state) { Object values[] = (Object[])state; super.restoreState(context, values[0]); value = (String)values[1]; size = (Integer)values[2]; } @Override public void encodeBegin(FacesContext context) throws IOException { // Wenn keine Groesse angegeben wurde default 3 String htmlTag = (size == null) ? "h3" : "h"+getSize().toString(); ResponseWriter writer = context.getResponseWriter(); writer.startElement(htmlTag, this); if(value == null) { writer.write(""); } else { writer.write(value); } writer.endElement(htmlTag); writer.flush(); } public String getValue() { if(value != null) { return value; } ValueExpression ve = getValueExpression("value"); if(ve != null) { return (String)ve.getValue(getFacesContext().getELContext()); } return null; } public void setValue(String value) { this.value = value; } public Integer getSize() { if(size != null) { return size; } ValueExpression ve = getValueExpression("size"); if(ve != null) { return (Integer)ve.getValue(getFacesContext().getELContext()); } return null; } public void setSize(Integer size) { if(size>6) size = 6; if(size<1) size = 1; this.size = size; } } HeadlineTag.java package tobi.web.component.headline; import javax.el.ValueExpression; import javax.faces.component.UIComponent; import javax.faces.webapp.UIComponentELTag; public class HeadlineTag extends UIComponentELTag { private ValueExpression value; private ValueExpression size; @Override public String getComponentType() { return "tobi.headline"; } @Override public String getRendererType() { // null, da wir hier keinen eigenen Render benutzen return null; } protected void setProperties(UIComponent component) { super.setProperties(component); HeadlineComponent headline = (HeadlineComponent)component; if(value != null) { if(value.isLiteralText()) { headline.getAttributes().put("value", value.getExpressionString()); } else { headline.setValueExpression("value", value); } } if(size != null) { if(size.isLiteralText()) { headline.getAttributes().put("size", size.getExpressionString()); } else { headline.setValueExpression("size", size); } } } @Override public void release() { super.release(); this.value = null; this.size = null; } public ValueExpression getValue() { return value; } public void setValue(ValueExpression value) { this.value = value; } public ValueExpression getSize() { return size; } public void setSize(ValueExpression size) { this.size = size; } } taglibrary.tld <?xml version="1.0" encoding="UTF-8" ?> <taglib xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-jsptaglibrary_2_1.xsd" version="2.1"> <description>Tobi Webclient Taglibrary</description> <tlib-version>1.0</tlib-version> <short-name>tobi-taglibrary</short-name> <uri>http://www.tobi.de/taglibrary</uri> <tag> <description>Eine Überschrift im HTML-Stil</description> <name>headline</name> <tag-class>tobi.web.component.headline.HeadlineTag</tag-class> <body-content>empty</body-content> <attribute> <description>Der Text der Überschrift</description> <name>value</name> <required>false</required> <rtexprvalue>true</rtexprvalue> </attribute> <attribute> <description>Die Größe der Überschrift nach HTML (h1 - h6)</description> <name>size</name> <required>false</required> <rtexprvalue>true</rtexprvalue> </attribute> </tag> </taglib> faces-config.xml <?xml version="1.0" encoding="UTF-8"?> <faces-config xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-facesconfig_1_2.xsd" version="1.2"> <component> <description>Erzeugt eine Überschrift nach HTML-Stil</description> <display-name>headline</display-name> <component-type>tobi.headline</component-type> <component-class>tobi.web.component.headline.HeadlineComponent</component-class> <attribute> <attribute-name>value</attribute-name> <attribute-class>java.lang.String</attribute-class> </attribute> <attribute> <attribute-name>size</attribute-name> <attribute-class>java.lang.Integer</attribute-class> <default-value>3</default-value> </attribute> </component> </faces-config>

  Read the article

• Adding Polynomials (Linked Lists)......Bug Help

  - by Brian

  I have written a program that creates nodes that in this class are parts of polynomials and then the two polynomials get added together to become one polynomial (list of nodes). All my code compiles so the only problem I am having is that the nodes are not inserting into the polynomial via the insert method I have in polynomial.java and when running the program it does create nodes and displays them in the 2x^2 format but when it comes to add the polynomials together it displays o as the polynomials, so if anyone can figure out whats wrong and what I can do to fix it it would be much appreciated. Here is the code: import java.util.Scanner; class Polynomial{ public termNode head; public Polynomial() { head = null; } public boolean isEmpty() { return (head == null); } public void display() { if (head == null) System.out.print("0"); else for(termNode cur = head; cur != null; cur = cur.getNext()) { System.out.println(cur); } } public void insert(termNode newNode) { termNode prev = null; termNode cur = head; while (cur!=null && (newNode.compareTo(cur)<0)) { prev = null; cur = cur.getNext(); } if (prev == null) { newNode.setNext(head); head = newNode; } else { newNode.setNext(cur); prev.setNext(newNode); } } public void readPolynomial(Scanner kb) { boolean done = false; double coefficient; int exponent; termNode term; head = null; //UNLINK ANY PREVIOUS POLYNOMIAL System.out.println("Enter 0 and 0 to end."); System.out.print("coefficient: "); coefficient = kb.nextDouble(); System.out.println(coefficient); System.out.print("exponent: "); exponent = kb.nextInt(); System.out.println(exponent); done = (coefficient == 0 && exponent == 0); while(!done) { Polynomial poly = new Polynomial(); term = new termNode(coefficient,exponent); System.out.println(term); poly.insert(term); System.out.println("Enter 0 and 0 to end."); System.out.print("coefficient: "); coefficient = kb.nextDouble(); System.out.println(coefficient); System.out.print("exponent: "); exponent = kb.nextInt(); System.out.println(exponent); done = (coefficient==0 && exponent==0); } } public static Polynomial add(Polynomial p, Polynomial q) { Polynomial r = new Polynomial(); double coefficient; int exponent; termNode first = p.head; termNode second = q.head; termNode sum = r.head; termNode term; while (first != null && second != null) { if (first.getExp() == second.getExp()) { if (first.getCoeff() != 0 && second.getCoeff() != 0); { double addCoeff = first.getCoeff() + second.getCoeff(); term = new termNode(addCoeff,first.getExp()); sum.setNext(term); first.getNext(); second.getNext(); } } else if (first.getExp() < second.getExp()) { sum.setNext(second); term = new termNode(second.getCoeff(),second.getExp()); sum.setNext(term); second.getNext(); } else { sum.setNext(first); term = new termNode(first.getNext()); sum.setNext(term); first.getNext(); } } while (first != null) { sum.setNext(first); } while (second != null) { sum.setNext(second); } return r; } } Here is my Node class: class termNode implements Comparable { private int exp; private double coeff; private termNode next; public termNode(double coefficient, int exponent) { coeff = coefficient; exp = exponent; next = null; } public termNode(termNode inTermNode) { coeff = inTermNode.coeff; exp = inTermNode.exp; } public void setData(double coefficient, int exponent) { coefficient = coeff; exponent = exp; } public double getCoeff() { return coeff; } public int getExp() { return exp; } public void setNext(termNode link) { next = link; } public termNode getNext() { return next; } public String toString() { if (exp == 0) { return(coeff + " "); } else if (exp == 1) { return(coeff + "x"); } else { return(coeff + "x^" + exp); } } public int compareTo(Object other) { if(exp ==((termNode) other).exp) return 0; else if(exp < ((termNode) other).exp) return -1; else return 1; } } And here is my Test class to run the program. import java.util.Scanner; class PolyTest{ public static void main(String [] args) { Scanner kb = new Scanner(System.in); Polynomial r; Polynomial p = new Polynomial(); System.out.println("Enter first polynomial."); p.readPolynomial(kb); Polynomial q = new Polynomial(); System.out.println(); System.out.println("Enter second polynomial."); q.readPolynomial(kb); r = Polynomial.add(p,q); System.out.println(); System.out.print("The sum of "); p.display(); System.out.print(" and "); q.display(); System.out.print(" is "); r.display(); } }

  Read the article

• Getting the count of rows in a Java resultset

  - by Mr Morgan

  Hello Does anyone know a better way of getting the number of rows in a Java resultset returned from a MySQL database? I'm currently using this: public static int getResultSetRowCount(ResultSet resultSet) { int size = 0; try { resultSet.last(); size = resultSet.getRow(); resultSet.beforeFirst(); } catch(Exception ex) { return 0; } return size; } But am open to alternatives. The resultset returned is not going to be the total number of rows read from the database so I don;t think I can use SQL COUNT. Thanks Mr Morgan.

  Read the article

• Suggestions for duplicate file finder algorithm (using C)

  - by Andrei Ciobanu

  Hello, I wanted to write a program that test if two files are duplicates (have exactly the same content). First I test if the files have the same sizes, and if they have i start to compare their contents. My first idea, was to "split" the files into fixed size blocks, then start a thread for every block, fseek to startup character of every block and continue the comparisons in parallel. When a comparison from a thread fails, the other working threads are canceled, and the program exits out of the thread spawning loop. The code looks like this: dupf.h #ifndef __NM__DUPF__H__ #define __NM__DUPF__H__ #define NUM_THREADS 15 #define BLOCK_SIZE 8192 /* Thread argument structure */ struct thread_arg_s { const char *name_f1; /* First file name */ const char *name_f2; /* Second file name */ int cursor; /* Where to seek in the file */ }; typedef struct thread_arg_s thread_arg; /** * 'arg' is of type thread_arg. * Checks if the specified file blocks are * duplicates. */ void *check_block_dup(void *arg); /** * Checks if two files are duplicates */ int check_dup(const char *name_f1, const char *name_f2); /** * Returns a valid pointer to a file. * If the file (given by the path/name 'fname') cannot be opened * in 'mode', the program is interrupted an error message is shown. **/ FILE *safe_fopen(const char *name, const char *mode); #endif dupf.c #include <errno.h> #include <pthread.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <sys/types.h> #include <sys/stat.h> #include <unistd.h> #include "dupf.h" FILE *safe_fopen(const char *fname, const char *mode) { FILE *f = NULL; f = fopen(fname, mode); if (f == NULL) { char emsg[255]; sprintf(emsg, "FOPEN() %s\t", fname); perror(emsg); exit(-1); } return (f); } void *check_block_dup(void *arg) { const char *name_f1 = NULL, *name_f2 = NULL; /* File names */ FILE *f1 = NULL, *f2 = NULL; /* Streams */ int cursor = 0; /* Reading cursor */ char buff_f1[BLOCK_SIZE], buff_f2[BLOCK_SIZE]; /* Character buffers */ int rchars_1, rchars_2; /* Readed characters */ /* Initializing variables from 'arg' */ name_f1 = ((thread_arg*)arg)->name_f1; name_f2 = ((thread_arg*)arg)->name_f2; cursor = ((thread_arg*)arg)->cursor; /* Opening files */ f1 = safe_fopen(name_f1, "r"); f2 = safe_fopen(name_f2, "r"); /* Setup cursor in files */ fseek(f1, cursor, SEEK_SET); fseek(f2, cursor, SEEK_SET); /* Initialize buffers */ rchars_1 = fread(buff_f1, 1, BLOCK_SIZE, f1); rchars_2 = fread(buff_f2, 1, BLOCK_SIZE, f2); if (rchars_1 != rchars_2) { /* fread failed to read the same portion. * program cannot continue */ perror("ERROR WHEN READING BLOCK"); exit(-1); } while (rchars_1-->0) { if (buff_f1[rchars_1] != buff_f2[rchars_1]) { /* Different characters */ fclose(f1); fclose(f2); pthread_exit("notdup"); } } /* Close streams */ fclose(f1); fclose(f2); pthread_exit("dup"); } int check_dup(const char *name_f1, const char *name_f2) { int num_blocks = 0; /* Number of 'blocks' to check */ int num_tsp = 0; /* Number of threads spawns */ int tsp_iter = 0; /* Iterator for threads spawns */ pthread_t *tsp_threads = NULL; thread_arg *tsp_threads_args = NULL; int tsp_threads_iter = 0; int thread_c_res = 0; /* Thread creation result */ int thread_j_res = 0; /* Thread join res */ int loop_res = 0; /* Function result */ int cursor; struct stat buf_f1; struct stat buf_f2; if (name_f1 == NULL || name_f2 == NULL) { /* Invalid input parameters */ perror("INVALID FNAMES\t"); return (-1); } if (stat(name_f1, &buf_f1) != 0 || stat(name_f2, &buf_f2) != 0) { /* Stat fails */ char emsg[255]; sprintf(emsg, "STAT() ERROR: %s %s\t", name_f1, name_f2); perror(emsg); return (-1); } if (buf_f1.st_size != buf_f2.st_size) { /* File have different sizes */ return (1); } /* Files have the same size, function exec. is continued */ num_blocks = (buf_f1.st_size / BLOCK_SIZE) + 1; num_tsp = (num_blocks / NUM_THREADS) + 1; cursor = 0; for (tsp_iter = 0; tsp_iter < num_tsp; tsp_iter++) { loop_res = 0; /* Create threads array for this spawn */ tsp_threads = malloc(NUM_THREADS * sizeof(*tsp_threads)); if (tsp_threads == NULL) { perror("TSP_THREADS ALLOC FAILURE\t"); return (-1); } /* Create arguments for every thread in the current spawn */ tsp_threads_args = malloc(NUM_THREADS * sizeof(*tsp_threads_args)); if (tsp_threads_args == NULL) { perror("TSP THREADS ARGS ALLOCA FAILURE\t"); return (-1); } /* Initialize arguments and create threads */ for (tsp_threads_iter = 0; tsp_threads_iter < NUM_THREADS; tsp_threads_iter++) { if (cursor >= buf_f1.st_size) { break; } tsp_threads_args[tsp_threads_iter].name_f1 = name_f1; tsp_threads_args[tsp_threads_iter].name_f2 = name_f2; tsp_threads_args[tsp_threads_iter].cursor = cursor; thread_c_res = pthread_create( &tsp_threads[tsp_threads_iter], NULL, check_block_dup, (void*)&tsp_threads_args[tsp_threads_iter]); if (thread_c_res != 0) { perror("THREAD CREATION FAILURE"); return (-1); } cursor+=BLOCK_SIZE; } /* Join last threads and get their status */ while (tsp_threads_iter-->0) { void *thread_res = NULL; thread_j_res = pthread_join(tsp_threads[tsp_threads_iter], &thread_res); if (thread_j_res != 0) { perror("THREAD JOIN FAILURE"); return (-1); } if (strcmp((char*)thread_res, "notdup")==0) { loop_res++; /* Closing other threads and exiting by condition * from loop. */ while (tsp_threads_iter-->0) { pthread_cancel(tsp_threads[tsp_threads_iter]); } } } free(tsp_threads); free(tsp_threads_args); if (loop_res > 0) { break; } } return (loop_res > 0) ? 1 : 0; } The function works fine (at least for what I've tested). Still, some guys from #C (freenode) suggested that the solution is overly complicated, and it may perform poorly because of parallel reading on hddisk. What I want to know: Is the threaded approach flawed by default ? Is fseek() so slow ? Is there a way to somehow map the files to memory and then compare them ?

  Read the article

< Previous Page | 81 82 83 84 85 86 87 88 89 90 91 92  | Next Page >