Search Results

Search found 50247 results on 2010 pages for 'base class'.

Page 354/2010 | < Previous Page | 350 351 352 353 354 355 356 357 358 359 360 361  | Next Page >

• Does anyone really understand how HFSC scheduling in Linux/BSD works?

  - by Mecki

  I read the original SIGCOMM '97 PostScript paper about HFSC, it is very technically, but I understand the basic concept. Instead of giving a linear service curve (as with pretty much every other scheduling algorithm), you can specify a convex or concave service curve and thus it is possible to decouple bandwidth and delay. However, even though this paper mentions to kind of scheduling algorithms being used (real-time and link-share), it always only mentions ONE curve per scheduling class (the decoupling is done by specifying this curve, only one curve is needed for that). Now HFSC has been implemented for BSD (OpenBSD, FreeBSD, etc.) using the ALTQ scheduling framework and it has been implemented Linux using the TC scheduling framework (part of iproute2). Both implementations added two additional service curves, that were NOT in the original paper! A real-time service curve and an upper-limit service curve. Again, please note that the original paper mentions two scheduling algorithms (real-time and link-share), but in that paper both work with one single service curve. There never have been two independent service curves for either one as you currently find in BSD and Linux. Even worse, some version of ALTQ seems to add an additional queue priority to HSFC (there is no such thing as priority in the original paper either). I found several BSD HowTo's mentioning this priority setting (even though the man page of the latest ALTQ release knows no such parameter for HSFC, so officially it does not even exist). This all makes the HFSC scheduling even more complex than the algorithm described in the original paper and there are tons of tutorials on the Internet that often contradict each other, one claiming the opposite of the other one. This is probably the main reason why nobody really seems to understand how HFSC scheduling really works. Before I can ask my questions, we need a sample setup of some kind. I'll use a very simple one as seen in the image below: Here are some questions I cannot answer because the tutorials contradict each other: What for do I need a real-time curve at all? Assuming A1, A2, B1, B2 are all 128 kbit/s link-share (no real-time curve for either one), then each of those will get 128 kbit/s if the root has 512 kbit/s to distribute (and A and B are both 256 kbit/s of course), right? Why would I additionally give A1 and B1 a real-time curve with 128 kbit/s? What would this be good for? To give those two a higher priority? According to original paper I can give them a higher priority by using a curve, that's what HFSC is all about after all. By giving both classes a curve of [256kbit/s 20ms 128kbit/s] both have twice the priority than A2 and B2 automatically (still only getting 128 kbit/s on average) Does the real-time bandwidth count towards the link-share bandwidth? E.g. if A1 and B1 both only have 64kbit/s real-time and 64kbit/s link-share bandwidth, does that mean once they are served 64kbit/s via real-time, their link-share requirement is satisfied as well (they might get excess bandwidth, but lets ignore that for a second) or does that mean they get another 64 kbit/s via link-share? So does each class has a bandwidth "requirement" of real-time plus link-share? Or does a class only have a higher requirement than the real-time curve if the link-share curve is higher than the real-time curve (current link-share requirement equals specified link-share requirement minus real-time bandwidth already provided to this class)? Is upper limit curve applied to real-time as well, only to link-share, or maybe to both? Some tutorials say one way, some say the other way. Some even claim upper-limit is the maximum for real-time bandwidth + link-share bandwidth? What is the truth? Assuming A2 and B2 are both 128 kbit/s, does it make any difference if A1 and B1 are 128 kbit/s link-share only, or 64 kbit/s real-time and 128 kbit/s link-share, and if so, what difference? If I use the seperate real-time curve to increase priorities of classes, why would I need "curves" at all? Why is not real-time a flat value and link-share also a flat value? Why are both curves? The need for curves is clear in the original paper, because there is only one attribute of that kind per class. But now, having three attributes (real-time, link-share, and upper-limit) what for do I still need curves on each one? Why would I want the curves shape (not average bandwidth, but their slopes) to be different for real-time and link-share traffic? According to the little documentation available, real-time curve values are totally ignored for inner classes (class A and B), they are only applied to leaf classes (A1, A2, B1, B2). If that is true, why does the ALTQ HFSC sample configuration (search for 3.3 Sample configuration) set real-time curves on inner classes and claims that those set the guaranteed rate of those inner classes? Isn't that completely pointless? (note: pshare sets the link-share curve in ALTQ and grate the real-time curve; you can see this in the paragraph above the sample configuration). Some tutorials say the sum of all real-time curves may not be higher than 80% of the line speed, others say it must not be higher than 70% of the line speed. Which one is right or are they maybe both wrong? One tutorial said you shall forget all the theory. No matter how things really work (schedulers and bandwidth distribution), imagine the three curves according to the following "simplified mind model": real-time is the guaranteed bandwidth that this class will always get. link-share is the bandwidth that this class wants to become fully satisfied, but satisfaction cannot be guaranteed. In case there is excess bandwidth, the class might even get offered more bandwidth than necessary to become satisfied, but it may never use more than upper-limit says. For all this to work, the sum of all real-time bandwidths may not be above xx% of the line speed (see question above, the percentage varies). Question: Is this more or less accurate or a total misunderstanding of HSFC? And if assumption above is really accurate, where is prioritization in that model? E.g. every class might have a real-time bandwidth (guaranteed), a link-share bandwidth (not guaranteed) and an maybe an upper-limit, but still some classes have higher priority needs than other classes. In that case I must still prioritize somehow, even among real-time traffic of those classes. Would I prioritize by the slope of the curves? And if so, which curve? The real-time curve? The link-share curve? The upper-limit curve? All of them? Would I give all of them the same slope or each a different one and how to find out the right slope? I still haven't lost hope that there exists at least a hand full of people in this world that really understood HFSC and are able to answer all these questions accurately. And doing so without contradicting each other in the answers would be really nice ;-)

  Read the article

• Does anyone really understand how HFSC scheduling in Linux/BSD works?

  - by Mecki

  I read the original SIGCOMM '97 PostScript paper about HFSC, it is very technically, but I understand the basic concept. Instead of giving a linear service curve (as with pretty much every other scheduling algorithm), you can specify a convex or concave service curve and thus it is possible to decouple bandwidth and delay. However, even though this paper mentions to kind of scheduling algorithms being used (real-time and link-share), it always only mentions ONE curve per scheduling class (the decoupling is done by specifying this curve, only one curve is needed for that). Now HFSC has been implemented for BSD (OpenBSD, FreeBSD, etc.) using the ALTQ scheduling framework and it has been implemented Linux using the TC scheduling framework (part of iproute2). Both implementations added two additional service curves, that were NOT in the original paper! A real-time service curve and an upper-limit service curve. Again, please note that the original paper mentions two scheduling algorithms (real-time and link-share), but in that paper both work with one single service curve. There never have been two independent service curves for either one as you currently find in BSD and Linux. Even worse, some version of ALTQ seems to add an additional queue priority to HSFC (there is no such thing as priority in the original paper either). I found several BSD HowTo's mentioning this priority setting (even though the man page of the latest ALTQ release knows no such parameter for HSFC, so officially it does not even exist). This all makes the HFSC scheduling even more complex than the algorithm described in the original paper and there are tons of tutorials on the Internet that often contradict each other, one claiming the opposite of the other one. This is probably the main reason why nobody really seems to understand how HFSC scheduling really works. Before I can ask my questions, we need a sample setup of some kind. I'll use a very simple one as seen in the image below: Here are some questions I cannot answer because the tutorials contradict each other: What for do I need a real-time curve at all? Assuming A1, A2, B1, B2 are all 128 kbit/s link-share (no real-time curve for either one), then each of those will get 128 kbit/s if the root has 512 kbit/s to distribute (and A and B are both 256 kbit/s of course), right? Why would I additionally give A1 and B1 a real-time curve with 128 kbit/s? What would this be good for? To give those two a higher priority? According to original paper I can give them a higher priority by using a curve, that's what HFSC is all about after all. By giving both classes a curve of [256kbit/s 20ms 128kbit/s] both have twice the priority than A2 and B2 automatically (still only getting 128 kbit/s on average) Does the real-time bandwidth count towards the link-share bandwidth? E.g. if A1 and B1 both only have 64kbit/s real-time and 64kbit/s link-share bandwidth, does that mean once they are served 64kbit/s via real-time, their link-share requirement is satisfied as well (they might get excess bandwidth, but lets ignore that for a second) or does that mean they get another 64 kbit/s via link-share? So does each class has a bandwidth "requirement" of real-time plus link-share? Or does a class only have a higher requirement than the real-time curve if the link-share curve is higher than the real-time curve (current link-share requirement equals specified link-share requirement minus real-time bandwidth already provided to this class)? Is upper limit curve applied to real-time as well, only to link-share, or maybe to both? Some tutorials say one way, some say the other way. Some even claim upper-limit is the maximum for real-time bandwidth + link-share bandwidth? What is the truth? Assuming A2 and B2 are both 128 kbit/s, does it make any difference if A1 and B1 are 128 kbit/s link-share only, or 64 kbit/s real-time and 128 kbit/s link-share, and if so, what difference? If I use the seperate real-time curve to increase priorities of classes, why would I need "curves" at all? Why is not real-time a flat value and link-share also a flat value? Why are both curves? The need for curves is clear in the original paper, because there is only one attribute of that kind per class. But now, having three attributes (real-time, link-share, and upper-limit) what for do I still need curves on each one? Why would I want the curves shape (not average bandwidth, but their slopes) to be different for real-time and link-share traffic? According to the little documentation available, real-time curve values are totally ignored for inner classes (class A and B), they are only applied to leaf classes (A1, A2, B1, B2). If that is true, why does the ALTQ HFSC sample configuration (search for 3.3 Sample configuration) set real-time curves on inner classes and claims that those set the guaranteed rate of those inner classes? Isn't that completely pointless? (note: pshare sets the link-share curve in ALTQ and grate the real-time curve; you can see this in the paragraph above the sample configuration). Some tutorials say the sum of all real-time curves may not be higher than 80% of the line speed, others say it must not be higher than 70% of the line speed. Which one is right or are they maybe both wrong? One tutorial said you shall forget all the theory. No matter how things really work (schedulers and bandwidth distribution), imagine the three curves according to the following "simplified mind model": real-time is the guaranteed bandwidth that this class will always get. link-share is the bandwidth that this class wants to become fully satisfied, but satisfaction cannot be guaranteed. In case there is excess bandwidth, the class might even get offered more bandwidth than necessary to become satisfied, but it may never use more than upper-limit says. For all this to work, the sum of all real-time bandwidths may not be above xx% of the line speed (see question above, the percentage varies). Question: Is this more or less accurate or a total misunderstanding of HSFC? And if assumption above is really accurate, where is prioritization in that model? E.g. every class might have a real-time bandwidth (guaranteed), a link-share bandwidth (not guaranteed) and an maybe an upper-limit, but still some classes have higher priority needs than other classes. In that case I must still prioritize somehow, even among real-time traffic of those classes. Would I prioritize by the slope of the curves? And if so, which curve? The real-time curve? The link-share curve? The upper-limit curve? All of them? Would I give all of them the same slope or each a different one and how to find out the right slope? I still haven't lost hope that there exists at least a hand full of people in this world that really understood HFSC and are able to answer all these questions accurately. And doing so without contradicting each other in the answers would be really nice ;-)

  Read the article

• Using custom DataContractResolver in WCF, to transport inheritance trees involving generics

  - by Benson

  I've got a WCF service, in which there are operations which accept a non-generic base class as parameter. [DataContract] class Foo { ... } This base class is in turn inherited, by such generics classes as [DataContract] class Bar : Foo { ... } To get this to work, I'd previously have to register KnownTypes for the Foo class, and have these include all possible variations of Bar (such as Bar, Bar and even Bar). With the DataContractResolver in .NET 4, however, I should be able to build a resolver which properly stores (and restores) the classes. My questions: Are DataContractResolvers typically only used on the service side, and not by the client? If so, how would that be useful in this scenario? Am I wrong to write a DataContractResolver which serializes the fully qualified type name of a generic type, such as Bar1[List1[string, mscorlib], mscorlib] ? Couldn't the same DataContractResolver on the client side restore these types?

  Read the article

• TFS 2010 SDK: Connecting to TFS 2010 Programmatically&ndash;Part 1

  - by Tarun Arora

  Technorati Tags: Team Foundation Server 2010,TFS 2010 SDK,TFS API,TFS Programming,TFS ALM   Download Working Demo Great! You have reached that point where you would like to extend TFS 2010. The first step is to connect to TFS programmatically. 1. Download TFS 2010 SDK => http://visualstudiogallery.msdn.microsoft.com/25622469-19d8-4959-8e5c-4025d1c9183d?SRC=VSIDE 2. Alternatively you can also download this from the visual studio extension manager 3. Create a new Windows Forms Application project and add reference to TFS Common and client dlls Note - If Microsoft.TeamFoundation.Client and Microsoft.TeamFoundation.Common do not appear on the .NET tab of the References dialog box, use the Browse tab to add the assemblies. You can find them at %ProgramFiles%\Microsoft Visual Studio 10.0\Common7\IDE\ReferenceAssemblies\v2.0. using Microsoft.TeamFoundation.Client; using Microsoft.TeamFoundation.Framework.Client; using Microsoft.TeamFoundation.Framework.Common;   4. There are several ways to connect to TFS, the two classes of interest are, Option 1 – Class – TfsTeamProjectCollectionClass namespace Microsoft.TeamFoundation.Client { public class TfsTeamProjectCollection : TfsConnection { public TfsTeamProjectCollection(RegisteredProjectCollection projectCollection); public TfsTeamProjectCollection(Uri uri); public TfsTeamProjectCollection(RegisteredProjectCollection projectCollection, IdentityDescriptor identityToImpersonate); public TfsTeamProjectCollection(Uri uri, ICredentials credentials); public TfsTeamProjectCollection(Uri uri, ICredentialsProvider credentialsProvider); public TfsTeamProjectCollection(Uri uri, IdentityDescriptor identityToImpersonate); public TfsTeamProjectCollection(RegisteredProjectCollection projectCollection, ICredentials credentials, ICredentialsProvider credentialsProvider); public TfsTeamProjectCollection(Uri uri, ICredentials credentials, ICredentialsProvider credentialsProvider); public TfsTeamProjectCollection(RegisteredProjectCollection projectCollection, ICredentials credentials, ICredentialsProvider credentialsProvider, IdentityDescriptor identityToImpersonate); public TfsTeamProjectCollection(Uri uri, ICredentials credentials, ICredentialsProvider credentialsProvider, IdentityDescriptor identityToImpersonate); public override CatalogNode CatalogNode { get; } public TfsConfigurationServer ConfigurationServer { get; internal set; } public override string Name { get; } public static Uri GetFullyQualifiedUriForName(string name); protected override object GetServiceInstance(Type serviceType, object serviceInstance); protected override object InitializeTeamFoundationObject(string fullName, object instance); } } Option 2 – Class – TfsConfigurationServer namespace Microsoft.TeamFoundation.Client { public class TfsConfigurationServer : TfsConnection { public TfsConfigurationServer(RegisteredConfigurationServer application); public TfsConfigurationServer(Uri uri); public TfsConfigurationServer(RegisteredConfigurationServer application, IdentityDescriptor identityToImpersonate); public TfsConfigurationServer(Uri uri, ICredentials credentials); public TfsConfigurationServer(Uri uri, ICredentialsProvider credentialsProvider); public TfsConfigurationServer(Uri uri, IdentityDescriptor identityToImpersonate); public TfsConfigurationServer(RegisteredConfigurationServer application, ICredentials credentials, ICredentialsProvider credentialsProvider); public TfsConfigurationServer(Uri uri, ICredentials credentials, ICredentialsProvider credentialsProvider); public TfsConfigurationServer(RegisteredConfigurationServer application, ICredentials credentials, ICredentialsProvider credentialsProvider, IdentityDescriptor identityToImpersonate); public TfsConfigurationServer(Uri uri, ICredentials credentials, ICredentialsProvider credentialsProvider, IdentityDescriptor identityToImpersonate); public override CatalogNode CatalogNode { get; } public override string Name { get; } protected override object GetServiceInstance(Type serviceType, object serviceInstance); public TfsTeamProjectCollection GetTeamProjectCollection(Guid collectionId); protected override object InitializeTeamFoundationObject(string fullName, object instance); } }   Note – The TeamFoundationServer class is obsolete. Use the TfsTeamProjectCollection or TfsConfigurationServer classes to talk to a 2010 Team Foundation Server. In order to talk to a 2005 or 2008 Team Foundation Server use the TfsTeamProjectCollection class. 5. Sample code for programmatically connecting to TFS 2010 using the TFS 2010 API How do i know what the URI of my TFS server is, Note – You need to be have Team Project Collection view details permission in order to connect, expect to receive an authorization failure message if you do not have sufficient permissions. Case 1: Connect by Uri string _myUri = @"https://tfs.codeplex.com:443/tfs/tfs30"; TfsConfigurationServer configurationServer = TfsConfigurationServerFactory.GetConfigurationServer(new Uri(_myUri)); Case 2: Connect by Uri, prompt for credentials string _myUri = @"https://tfs.codeplex.com:443/tfs/tfs30"; TfsConfigurationServer configurationServer = TfsConfigurationServerFactory.GetConfigurationServer(new Uri(_myUri), new UICredentialsProvider()); configurationServer.EnsureAuthenticated(); Case 3: Connect by Uri, custom credentials In order to use this method of connectivity you need to implement the interface ICredentailsProvider public class ConnectByImplementingCredentialsProvider : ICredentialsProvider { public ICredentials GetCredentials(Uri uri, ICredentials iCredentials) { return new NetworkCredential("UserName", "Password", "Domain"); } public void NotifyCredentialsAuthenticated(Uri uri) { throw new ApplicationException("Unable to authenticate"); } } And now consume the implementation of the interface, string _myUri = @"https://tfs.codeplex.com:443/tfs/tfs30"; ConnectByImplementingCredentialsProvider connect = new ConnectByImplementingCredentialsProvider(); ICredentials iCred = new NetworkCredential("UserName", "Password", "Domain"); connect.GetCredentials(new Uri(_myUri), iCred); TfsConfigurationServer configurationServer = TfsConfigurationServerFactory.GetConfigurationServer(new Uri(_myUri), connect); configurationServer.EnsureAuthenticated();   6. Programmatically query TFS 2010 using the TFS SDK for all Team Project Collections and retrieve all Team Projects and output the display name and description of each team project. CatalogNode catalogNode = configurationServer.CatalogNode; ReadOnlyCollection<CatalogNode> tpcNodes = catalogNode.QueryChildren( new Guid[] { CatalogResourceTypes.ProjectCollection }, false, CatalogQueryOptions.None); // tpc = Team Project Collection foreach (CatalogNode tpcNode in tpcNodes) { Guid tpcId = new Guid(tpcNode.Resource.Properties["InstanceId"]); TfsTeamProjectCollection tpc = configurationServer.GetTeamProjectCollection(tpcId); // Get catalog of tp = 'Team Projects' for the tpc = 'Team Project Collection' var tpNodes = tpcNode.QueryChildren( new Guid[] { CatalogResourceTypes.TeamProject }, false, CatalogQueryOptions.None); foreach (var p in tpNodes) { Debug.Write(Environment.NewLine + " Team Project : " + p.Resource.DisplayName + " - " + p.Resource.Description + Environment.NewLine); } }   Output   You can download a working demo that uses TFS SDK 2010 to programmatically connect to TFS 2010. Screen Shots of the attached demo application, Share this post :

  Read the article

• Guarding against CSRF Attacks in ASP.NET MVC2

  - by srkirkland

  Alongside XSS (Cross Site Scripting) and SQL Injection, Cross-site Request Forgery (CSRF) attacks represent the three most common and dangerous vulnerabilities to common web applications today. CSRF attacks are probably the least well known but they are relatively easy to exploit and extremely and increasingly dangerous. For more information on CSRF attacks, see these posts by Phil Haack and Steve Sanderson. The recognized solution for preventing CSRF attacks is to put a user-specific token as a hidden field inside your forms, then check that the right value was submitted. It's best to use a random value which you’ve stored in the visitor’s Session collection or into a Cookie (so an attacker can't guess the value). ASP.NET MVC to the rescue ASP.NET MVC provides an HTMLHelper called AntiForgeryToken(). When you call <%= Html.AntiForgeryToken() %> in a form on your page you will get a hidden input and a Cookie with a random string assigned. Next, on your target Action you need to include [ValidateAntiForgeryToken], which handles the verification that the correct token was supplied. Good, but we can do better Using the AntiForgeryToken is actually quite an elegant solution, but adding [ValidateAntiForgeryToken] on all of your POST methods is not very DRY, and worse can be easily forgotten. Let's see if we can make this easier on the program but moving from an "Opt-In" model of protection to an "Opt-Out" model. Using AntiForgeryToken by default In order to mandate the use of the AntiForgeryToken, we're going to create an ActionFilterAttribute which will do the anti-forgery validation on every POST request. First, we need to create a way to Opt-Out of this behavior, so let's create a quick action filter called BypassAntiForgeryToken: [AttributeUsage(AttributeTargets.Method, AllowMultiple=false)] public class BypassAntiForgeryTokenAttribute : ActionFilterAttribute { } Now we are ready to implement the main action filter which will force anti forgery validation on all post actions within any class it is defined on: [AttributeUsage(AttributeTargets.Class, AllowMultiple = false)] public class UseAntiForgeryTokenOnPostByDefault : ActionFilterAttribute { public override void OnActionExecuting(ActionExecutingContext filterContext) { if (ShouldValidateAntiForgeryTokenManually(filterContext)) { var authorizationContext = new AuthorizationContext(filterContext.Controller.ControllerContext);   //Use the authorization of the anti forgery token, //which can't be inhereted from because it is sealed new ValidateAntiForgeryTokenAttribute().OnAuthorization(authorizationContext); }   base.OnActionExecuting(filterContext); }   /// <summary> /// We should validate the anti forgery token manually if the following criteria are met: /// 1. The http method must be POST /// 2. There is not an existing [ValidateAntiForgeryToken] attribute on the action /// 3. There is no [BypassAntiForgeryToken] attribute on the action /// </summary> private static bool ShouldValidateAntiForgeryTokenManually(ActionExecutingContext filterContext) { var httpMethod = filterContext.HttpContext.Request.HttpMethod;   //1. The http method must be POST if (httpMethod != "POST") return false;   // 2. There is not an existing anti forgery token attribute on the action var antiForgeryAttributes = filterContext.ActionDescriptor.GetCustomAttributes(typeof(ValidateAntiForgeryTokenAttribute), false);   if (antiForgeryAttributes.Length > 0) return false;   // 3. There is no [BypassAntiForgeryToken] attribute on the action var ignoreAntiForgeryAttributes = filterContext.ActionDescriptor.GetCustomAttributes(typeof(BypassAntiForgeryTokenAttribute), false);   if (ignoreAntiForgeryAttributes.Length > 0) return false;   return true; } } The code above is pretty straight forward -- first we check to make sure this is a POST request, then we make sure there aren't any overriding *AntiForgeryTokenAttributes on the action being executed. If we have a candidate then we call the ValidateAntiForgeryTokenAttribute class directly and execute OnAuthorization() on the current authorization context. Now on our base controller, you could use this new attribute to start protecting your site from CSRF vulnerabilities. [UseAntiForgeryTokenOnPostByDefault] public class ApplicationController : System.Web.Mvc.Controller { }   //Then for all of your controllers public class HomeController : ApplicationController {} What we accomplished If your base controller has the new default anti-forgery token attribute on it, when you don't use <%= Html.AntiForgeryToken() %> in a form (or of course when an attacker doesn't supply one), the POST action will throw the descriptive error message "A required anti-forgery token was not supplied or was invalid". Attack foiled! In summary, I think having an anti-CSRF policy by default is an effective way to protect your websites, and it turns out it is pretty easy to accomplish as well. Enjoy!

  Read the article

• How can I eager-load a child collection mapped to a non-primary key in NHibernate 2.1.2?

  - by David Rubin

  Hi, I have two objects with a many-to-many relationship between them, as follows: public class LeftHandSide { public LeftHandSide() { Name = String.Empty; Rights = new HashSet<RightHandSide>(); } public int Id { get; set; } public string Name { get; set; } public ICollection<RightHandSide> Rights { get; set; } } public class RightHandSide { public RightHandSide() { OtherProp = String.Empty; Lefts = new HashSet<LeftHandSide>(); } public int Id { get; set; } public string OtherProp { get; set; } public ICollection<LeftHandSide> Lefts { get; set; } } and I'm using a legacy database, so my mappings look like: Notice that LeftHandSide and RightHandSide are associated by a different column than RightHandSide's primary key. <class name="LeftHandSide" table="[dbo].[lefts]" lazy="false"> <id name="Id" column="ID" unsaved-value="0"> <generator class="identity" /> </id> <property name="Name" not-null="true" /> <set name="Rights" table="[dbo].[lefts2rights]"> <key column="leftId" /> <!-- THIS IS THE IMPORTANT BIT: I MUST USE PROPERTY-REF --> <many-to-many class="RightHandSide" column="rightProp" property-ref="OtherProp" /> </set> </class> <class name="RightHandSide" table="[dbo].[rights]" lazy="false"> <id name="Id" column="id" unsaved-value="0"> <generator class="identity" /> </id> <property name="OtherProp" column="otherProp" /> <set name="Lefts" table="[dbo].[lefts2rights]"> <!-- THIS IS THE IMPORTANT BIT: I MUST USE PROPERTY-REF --> <key column="rightProp" property-ref="OtherProp" /> <many-to-many class="LeftHandSide" column="leftId" /> </set> </class> The problem comes when I go to do a query: LeftHandSide lhs = _session.CreateCriteria<LeftHandSide>() .Add(Expression.IdEq(13)) .UniqueResult<LeftHandSide>(); works just fine. But LeftHandSide lhs = _session.CreateCriteria<LeftHandSide>() .Add(Expression.IdEq(13)) .SetFetchMode("Rights", FetchMode.Join) .UniqueResult<LeftHandSide>(); throws an exception (see below). Interestingly, RightHandSide rhs = _session.CreateCriteria<RightHandSide>() .Add(Expression.IdEq(127)) .SetFetchMode("Lefts", FetchMode.Join) .UniqueResult<RightHandSide>(); seems to be perfectly fine as well. NHibernate.Exceptions.GenericADOException Message: Error performing LoadByUniqueKey[SQL: SQL not available] Source: NHibernate StackTrace: c:\opt\nhibernate\2.1.2\source\src\NHibernate\Type\EntityType.cs(563,0): at NHibernate.Type.EntityType.LoadByUniqueKey(String entityName, String uniqueKeyPropertyName, Object key, ISessionImplementor session) c:\opt\nhibernate\2.1.2\source\src\NHibernate\Type\EntityType.cs(428,0): at NHibernate.Type.EntityType.ResolveIdentifier(Object value, ISessionImplementor session, Object owner) c:\opt\nhibernate\2.1.2\source\src\NHibernate\Type\EntityType.cs(300,0): at NHibernate.Type.EntityType.NullSafeGet(IDataReader rs, String[] names, ISessionImplementor session, Object owner) c:\opt\nhibernate\2.1.2\source\src\NHibernate\Persister\Collection\AbstractCollectionPersister.cs(695,0): at NHibernate.Persister.Collection.AbstractCollectionPersister.ReadElement(IDataReader rs, Object owner, String[] aliases, ISessionImplementor session) c:\opt\nhibernate\2.1.2\source\src\NHibernate\Collection\Generic\PersistentGenericSet.cs(54,0): at NHibernate.Collection.Generic.PersistentGenericSet`1.ReadFrom(IDataReader rs, ICollectionPersister role, ICollectionAliases descriptor, Object owner) c:\opt\nhibernate\2.1.2\source\src\NHibernate\Loader\Loader.cs(706,0): at NHibernate.Loader.Loader.ReadCollectionElement(Object optionalOwner, Object optionalKey, ICollectionPersister persister, ICollectionAliases descriptor, IDataReader rs, ISessionImplementor session) c:\opt\nhibernate\2.1.2\source\src\NHibernate\Loader\Loader.cs(385,0): at NHibernate.Loader.Loader.ReadCollectionElements(Object[] row, IDataReader resultSet, ISessionImplementor session) c:\opt\nhibernate\2.1.2\source\src\NHibernate\Loader\Loader.cs(326,0): at NHibernate.Loader.Loader.GetRowFromResultSet(IDataReader resultSet, ISessionImplementor session, QueryParameters queryParameters, LockMode[] lockModeArray, EntityKey optionalObjectKey, IList hydratedObjects, EntityKey[] keys, Boolean returnProxies) c:\opt\nhibernate\2.1.2\source\src\NHibernate\Loader\Loader.cs(453,0): at NHibernate.Loader.Loader.DoQuery(ISessionImplementor session, QueryParameters queryParameters, Boolean returnProxies) c:\opt\nhibernate\2.1.2\source\src\NHibernate\Loader\Loader.cs(236,0): at NHibernate.Loader.Loader.DoQueryAndInitializeNonLazyCollections(ISessionImplementor session, QueryParameters queryParameters, Boolean returnProxies) c:\opt\nhibernate\2.1.2\source\src\NHibernate\Loader\Loader.cs(1649,0): at NHibernate.Loader.Loader.DoList(ISessionImplementor session, QueryParameters queryParameters) c:\opt\nhibernate\2.1.2\source\src\NHibernate\Loader\Loader.cs(1568,0): at NHibernate.Loader.Loader.ListIgnoreQueryCache(ISessionImplementor session, QueryParameters queryParameters) c:\opt\nhibernate\2.1.2\source\src\NHibernate\Loader\Loader.cs(1562,0): at NHibernate.Loader.Loader.List(ISessionImplementor session, QueryParameters queryParameters, ISet`1 querySpaces, IType[] resultTypes) c:\opt\nhibernate\2.1.2\source\src\NHibernate\Loader\Criteria\CriteriaLoader.cs(73,0): at NHibernate.Loader.Criteria.CriteriaLoader.List(ISessionImplementor session) c:\opt\nhibernate\2.1.2\source\src\NHibernate\Impl\SessionImpl.cs(1936,0): at NHibernate.Impl.SessionImpl.List(CriteriaImpl criteria, IList results) c:\opt\nhibernate\2.1.2\source\src\NHibernate\Impl\CriteriaImpl.cs(246,0): at NHibernate.Impl.CriteriaImpl.List(IList results) c:\opt\nhibernate\2.1.2\source\src\NHibernate\Impl\CriteriaImpl.cs(237,0): at NHibernate.Impl.CriteriaImpl.List() c:\opt\nhibernate\2.1.2\source\src\NHibernate\Impl\CriteriaImpl.cs(398,0): at NHibernate.Impl.CriteriaImpl.UniqueResult() c:\opt\nhibernate\2.1.2\source\src\NHibernate\Impl\CriteriaImpl.cs(263,0): at NHibernate.Impl.CriteriaImpl.UniqueResult[T]() D:\proj\CMS3\branches\nh_auth\DomainModel2Tests\Authorization\TempTests.cs(46,0): at CMS.DomainModel.Authorization.TempTests.Test1() Inner Exception System.Collections.Generic.KeyNotFoundException Message: The given key was not present in the dictionary. Source: mscorlib StackTrace: at System.ThrowHelper.ThrowKeyNotFoundException() at System.Collections.Generic.Dictionary`2.get_Item(TKey key) c:\opt\nhibernate\2.1.2\source\src\NHibernate\Persister\Entity\AbstractEntityPersister.cs(2047,0): at NHibernate.Persister.Entity.AbstractEntityPersister.GetAppropriateUniqueKeyLoader(String propertyName, IDictionary`2 enabledFilters) c:\opt\nhibernate\2.1.2\source\src\NHibernate\Persister\Entity\AbstractEntityPersister.cs(2037,0): at NHibernate.Persister.Entity.AbstractEntityPersister.LoadByUniqueKey(String propertyName, Object uniqueKey, ISessionImplementor session) c:\opt\nhibernate\2.1.2\source\src\NHibernate\Type\EntityType.cs(552,0): at NHibernate.Type.EntityType.LoadByUniqueKey(String entityName, String uniqueKeyPropertyName, Object key, ISessionImplementor session) I'm using NHibernate 2.1.2 and I've been debugging into the NHibernate source, but I'm coming up empty. Any suggestions? Thanks so much!

  Read the article

• Entity Framework 4.0: Creating objects of correct type when using lazy loading

  - by DigiMortal

  In my posting about Entity Framework 4.0 and POCOs I introduced lazy loading in EF applications. EF uses proxy classes for lazy loading and this means we have new types in that come and go dynamically in runtime. We don’t have these types available when we write code but we cannot forget that EF may expect us to use dynamically generated types. In this posting I will give you simple hint how to use correct types in your code. The background of lazy loading and proxy classes As a first thing I will explain you in short what is proxy class. Business classes when designed correctly have no knowledge about their birth and death – they don’t know how they are created and they don’t know how their data is persisted. This is the responsibility of object runtime. When we use lazy loading we need a little bit different classes that know how to load data for properties when code accesses the property first time. As we cannot add this functionality to our business classes (they may be stored through more than one data access technology or by more than one Data Access Layer (DAL)) we create proxy classes that extend our business classes. If we have class called Product and product has lazy loaded property called Customer then we need proxy class, let’s say ProductProxy, that has same public signature as Product so we can use it INSTEAD OF product in our code. ProductProxy overrides Customer property. If customer is not asked then customer is null. But if we ask for Customer property then overridden property of ProductProxy loads it from database. This is how lazy loading works. Problem – two types for same thing As lazy loading may introduce dynamically generated proxy types we don’t know in our application code which type is returned. We cannot be sure that we have Product not ProductProxy returned. This leads us to the following question: how can we create Product of correct type if we don’t know the correct type? In EF solution is simple. Solution – use factory methods If you are using repositories and you are not using factories (imho it is pretty pointless with mapper) you can add factory methods to your EF based repositories. Take a look at this class. public class Event {     public int ID { get; set; }     public string Title { get; set; }     public string Location { get; set; }     public virtual Party Organizer { get; set; }     public DateTime Date { get; set; } } We have virtual member called Organizer. This property is virtual because we want to use lazy loading on this class so Organizer is loaded only when we ask it. EF provides us with method called CreateObject<T>(). CreateObject<T>() is member of ObjectContext class and it creates the object based on given type. In runtime proxy type for Event is created for us automatically and when we call CreateObject<T>() for Event it returns as object of Event proxy type. The factory method for events repository is as follows. public Event CreateEvent() {     var evt = _context.CreateObject<Event>();     return evt; } And we are done. Instead of creating factory classes we created factory methods that guarantee that created objects are of correct type. Conclusion Although lazy loading introduces some new objects we cannot use at design time because they live only in runtime we can write code without worrying about exact implementation type of object. This holds true until we have clean code and we don’t make any decisions based on object type. EF4.0 provides us with very simple factory method that create and return objects of correct type. All we had to do was adding factory methods to our repositories.

  Read the article

• How to parse invalid HTML with Perl?

  - by bodacydo

  I maintain a database of articles with HTML formatting. Unfortunately the editors who wrote articles didn't know proper HTML, so they often have written stuff like: <div class="highlight"><html><head></head><body><p>Note that ...</p></html></div> I tried using HTML::TreeBuilder to parse this HTML but after parsing it and dumping the resulting tree, all the elements between <div class="highlight">...</div> are gone. I'm left with just <div class="highlight"></div>. The editors often have also done things like: <div class="article"><style>@font-face { font-family: "Cambria"; }</style>Article starts here</div> Parsing this with HTML::TreeBuilder results in empty <div class="article"></div> again. Any ideas how to approach this broken HTML and actually make sense out of it?

  Read the article

• How to set child unordered list position?

  - by Joel

  Hi folks. I have a nav bar with children unordered lists nested under the main navbar items. My problem is on the inner list, when I position absolute, the inner list is centered to the page, and when I position relative, it is positioning inline with the parent list. I'm trying to get the first child item to line up directly under it's parent. /* OUTER LIST STYLING */ div#navbar2 { position:relative; width: 100%; border-top: solid #000 1px; border-bottom: solid #546F8B 1px; background-color: #546F8B; } div#navbar2 ul#navbar { padding: 0; margin: 10px 0; font-family: Arial, Helvetica, sans-serif; font-size: 16px; letter-spacing:1px; color: #FFF; white-space: nowrap; } div#navbar2 ul#navbar li { margin: 0 2px; list-style-type: none; display: inline; } div#navbar2 li a { text-decoration: none; color: #fff; padding: 10px 10px; } div#navbar2 li a:link { color: #FFF: } div#navbar2 li a:visited { color: #ffffff; } div#navbar2 li a:hover { color: #000; background-color: #FDFFC9; } /* INNER LIST STYLING */ div#navbar2 ul#navbar li ul.innerlist{ display: none; color:#000; } div#navbar2 ul#navbar li ul.innerlist li{ color:#000; } div#navbar2 ul#navbar li:hover ul.innerlist { position: absolute; display: inline; left: 0; width: 100%; margin: 40px 0 0px 0px; padding: 0px; color:#000; } div#navbar2 li.innerlist a { text-decoration: none; color: #000; padding: 10px 10px; } div#navbar2 li.innerlist a:link { color: #000: } div#navbar2 li.innerlist a:visited { color: #000; } div#navbar2 li.innerlist a:hover { color: #000; background-color: #FDFFC9; } And my html: <div id="navbar2"> <ul id="navbar"> <li id="index"><a href="index.php">About Rattletree</a></li> <li id="upcomingshows"><a href="upcomingshows.php">Calendar</a></li> <li id="booking"><a href="booking.php">Contact</a> <ul class="innerlist"> <li class="innerlist"><a href="#">Booking</a></li> <li class="innerlist"><a href="#">press</a></li> </ul> </li> <li id="instruments"><a href="instruments.php">The Band</a> <ul class="innerlist"> <li class="innerlist"><a href="#">The Instruments</a></li> <li class="innerlist"><a href="#">The Players</a></li> </ul> </li> <li id="classes"><a href="classes.php">Sights &amp; Sounds</a> <ul class="innerlist"> <li class="innerlist"><a href="#">Listen</a></li> <li class="innerlist"><a href="#">photos</a></li> <li class="innerlist"><a href="#">video</a></li> </ul> </li> <li id"classes"><a href="classes.php">Workshops &amp; Classes</a></li> </ul> </div> Thanks for any help!

  Read the article

• django admin: Add a "remove file" field for Image- or FileFields

  - by w-

  I was hunting around the net for a way to easily allow users to blank out imagefield/filefields they have set in the admin. I found this http://www.djangosnippets.org/snippets/894/ What was really interesting to me here was the code posted in the comment by rfugger remove_the_file = forms.BooleanField(required=False) def save(self, *args, **kwargs): object = super(self.__class__, self).save(*args, **kwargs) if self.cleaned_data.get('remove_the_file'): object.the_file = '' return object When i try to use this in my own form I basically added this to my admin.py which already had a BlahAdmin class BlahModelForm(forms.ModelForm): class Meta: model = Blah remove_img01 = forms.BooleanField(required=False) def save(self, *args, **kwargs): object = super(self.__class__, self).save(*args, **kwargs) if self.cleaned_data.get('remove_img01'): object.img01 = '' return object when i run it I get this error maximum recursion depth exceeded while calling a Python object at this line object = super(self.__class__, self).save(*args, **kwargs) When i think about it for a bit, it seems obvious that it is just infinitely calling itself causing the error. My problem is i can't figure out what is the correct way i should be doing this. Any suggestions? thanks

  Read the article

• Marshall a list of objects from VB6 to C#

  - by Andrew

  I have a development which requires the passing of objects between a VB6 application and a C# class library. The objects are defined in the C# class library and are used as parameters for methods exposed by other classes in the same library. The objects all contain simple string/numeric properties and so marshaling has been relatively painless. We now have a requirement to pass an object which contains a list of other objects. If I was coding this in VB6 I might have a class containing a collection as a member variable. In C# I might have a class with a List member variable. Is it possible to construct a C# class in such a way that the VB6 application could populate this inner list and marshal it successfully? I don't have a lot of experience here but I would guess Id have to use an array of Object types.

  Read the article

• Problem with deploying simple Spring MVC Portlet to Liferay 5.2.3

  - by Johannes Hipp

  Hello, I try to deploy a simple spring portlet in ext (I can't use Plugins SDK...) on Liferay 5.2.3 My portlet: ext-impl/src: package: com.ext.portlet.springmvc HelloWorldController.java [code] package com.ext.portlet.springmvc; import java.io.IOException; import javax.servlet.ServletException; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.springframework.web.servlet.ModelAndView; import org.springframework.web.servlet.mvc.Controller; public class HelloWorldController implements Controller { public ModelAndView handleRequest(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { String aMessage = "Hello World MVC!"; ModelAndView modelAndView = new ModelAndView("hello_world"); modelAndView.addObject("message", aMessage); return modelAndView; } } [/code] ext-lib: - jstr.jar - spring-webmvc.jar - spring-webmvc-portlet.jar - spring.jar - standard.jar ext-web/docroot/html/portlet/ext/springmvc/hello_world.jsp [code] <%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %> <html> <body> <p>This is my message: ${message}</p> </body> </html> [/code] ext-web/docroot/html/portlet/ext/springmvc/index.jsp [code] <html> <body> <p>Hi</p> </body> </html> [/code] ext-web/docroot/WEB-INF/springmvc-servlet.xml [code] <?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd"> <bean name="/hello_world.html" class="com.ext.portlet.springmvc.HelloWorldController"/> <bean id="viewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver"> <property name="viewClass" value="org.springframework.web.servlet.view.JstlView"/> <property name="prefix" value="/jsp/"/> <property name="suffix" value=".jsp"/> </bean> </beans> [/code] ext-web/docroot/WEB-INF/portlet-ext.xml [code] <portlet> <portlet-name>springmvc</portlet-name> <portlet-class>org.springframework.web.portlet.DispatcherPortlet</portlet-class> <supports> <mime-type>text/html</mime-type> <portlet-mode>view</portlet-mode> </supports> <portlet-info> <title>Simple JSP Portlet</title> </portlet-info> <security-role-ref> <role-name>power-user</role-name> </security-role-ref> <security-role-ref> <role-name>user</role-name> </security-role-ref> </portlet> [/code] ext-web/docroot/WEB-INF/web.xml [code] <?xml version="1.0"?> <web-app xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd" version="2.4"> <servlet> <servlet-name>springmvc</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping> <servlet-name>springmvc</servlet-name> <url-pattern>*.html</url-pattern> </servlet-mapping> <welcome-file-list> <welcome-file> jsp/index.jsp </welcome-file> </welcome-file-list> </web-app> [/code] Are there some mistakes? I get this error, when I try to deploy: [code] Website OC4J 10g (10.1.3) Default Web Site definiert ist. Error creating bean w ith name 'com.liferay.portal.kernel.captcha.CaptchaUtil' defined in class path r esource [META-INF/util-spring.xml]: Cannot create inner bean 'com.liferay.portal .captcha.CaptchaImpl#1424b7b' of type [com.liferay.portal.captcha.CaptchaImpl] w hile setting bean property 'captcha'; nested exception is org.springframework.be ans.factory.BeanCreationException: Error creating bean with name 'com.liferay.po rtal.captcha.CaptchaImpl#1424b7b' defined in class path resource [META-INF/util- spring.xml]: Instantiation of bean failed; nested exception is org.springframewo rk.beans.BeanInstantiationException: Could not instantiate bean class [com.lifer ay.portal.captcha.CaptchaImpl]: Constructor threw exception; nested exception is java.lang.NullPointerException [/code] Hope anybody can help me... Thank you very much. Best regards, Johannes

  Read the article

• JPA Entity (in multiple persistence-unit) in OSGi (Spring DM) Environnement is confusing me.

  - by Vincent Demeester

  Hi, I'm a bit confused about a strange behavior of my JPA's related objects. I have three bundle : The User bundle does contain some user-related objects, but mainly the User object. The Energy bundle does contain some energy-related objects, and particularly a ConsumptionTerminal which contains a List of User. The Index bundle does contain an Index object that has no dependency at all. My OSGi environment is the following : A DataSource bundle that provide 2 services : dataSource and jpaVendorAdapter. The three bundles. They consume dataSource and jpaVendorAdapter. Their module-context.xml file look like : And they all have a persistence.xml file : User <?xml version="1.0" encoding="UTF-8"?> <persistence> <persistence-unit name="securityPU" transaction-type="JTA"> <jta-data-source>java:/securityDataSourceService</jta-data-source> <class>net.nextep.amundsen.security.domain.User</class> <!-- [...] --> <exclude-unlisted-classes>true</exclude-unlisted-classes> <properties> <property name="eclipselink.logging.level" value="INFO" /> <property name="eclipselink.ddl-generation" value="create-tables" /> <property name="eclipselink.ddl-generation.output-mode" value="database" /> <property name="eclipselink.orm.throw.exceptions" value="true" /> </properties> </persistence-unit> </persistence> Energy <?xml version="1.0" encoding="UTF-8"?> <persistence> <persistence-unit name="energyPU" transaction-type="JTA"> <jta-data-source>java:/securityDataSourceService</jta-data-source> <class>net.nextep.amundsen.security.domain.User</class> <class>net.nextep.amundsen.energy.domain.User</class> <!-- [...] --> <exclude-unlisted-classes>true</exclude-unlisted-classes> <properties> <property name="eclipselink.logging.level" value="INFO" /> <property name="eclipselink.ddl-generation" value="create-tables" /> <property name="eclipselink.ddl-generation.output-mode" value="database" /> <property name="eclipselink.orm.throw.exceptions" value="true" /> </properties> </persistence-unit> </persistence> Index : This one has the most simple persistence.xml with just the Index class (no shared Class). I'm using named @PersistenceUnit annotation like @PersitenceUnit(name = 'securityPU') (for the User bundle). And finally, I'm using EclipseLink as Jpa provider and Spring DM (+ Spring DM Server in the development process) The problem is the following : When the User bundle is deployed, I'm able to persist User objects. When the User bundle and Energy bundles are both deployed, I'm not able to persist User objects (neither the Energy object). But I don't have any exception at all ! There is no problem at all with the Index bundle. The bug is dataSource independent (I tried with PostgreSQL and MySQL so far). My first conclusion was that the <class>net.nextep.amundsen.security.domain.User</class> in both persistence unit was causing the trouble. I tried without it (and hiding the User dependent object in the Energy bundle) but it failed too. I'm a bit confused about that bug. I'm also not quite sure about the transaction management in this context. I wasn't the one who designed this architecture (but I tell my intern OK without testing it.. shame on me) but if I could understand this bug and maybe fix it without rewrite the bundle (and break my intern work), I would appreciate. Am I doing something wrong ? (it's obvious, but what..) Did I miss something while reading documentation ? By the way, I'm also looking for some best practices or advices when it comes to JPA, EclipseLink (or whatever JPA Provider) and Spring DM (and OSGi in general). I found interesting slides from Mike Keith about this topic (by browsing Stackoverflow).

  Read the article

• When and where to call the RemoveHandler in VB.NET?

  - by marco.ragogna

  I am working to a VB.NET windows forms projet in .NET 1.1. And I have this type of architecture, very simplified. Public MustInherit Class BaseTestLogic Private _TimerPoll As Timer Public Sub New(ByVal sym As SymbolFileMng, ByVal cfg As LampTestConfig, ByVal daas As DaasManager, ByVal mcf As Elux.Wg.Lpd.MCFs.VMCF) AddHandler _TimerPoll.Tick, AddressOf TimerPoll_Tick End Sub End Class Public Class SpecificTestLogic Inherits BaseTestLogic End Class Depending of the type of test I am doing I create an instance of a specific test derived from BaseTestLogic. But I found that after hundreds of object creations I can have StackOverflow exception. I checked my code and saw that I forgot to remove the handler to Timer Tick. The question is, where and when is it correct to remove hadler? Do I need to implement the IDisposable interface in the base class and RemoveHandler in Dispose?

  Read the article

• Parse HTML with PHP's HTML DOMDocument

  - by Mint

  I was trying to do it with "getElementsByTagName", but it wasn't working, I'm new to using DOMDocument to parse HTML, as I used to use regex until yesterday some kind fokes here told me that DOMEDocument would be better for the job, so I'm giving it a try :) I google around for a while looking for some explains but didn't find anything that helped (not with the class anyway) So I want to capture "Capture this text 1" and "Capture this text 2" and so on. Doesn't look to hard, but I can't figure it out :( <div class="main"> <div class="text"> Capture this text 1 </div> </div> <div class="main"> <div class="text"> Capture this text 2 </div> </div>

  Read the article

• Rendering ASP.NET MVC Razor Views outside of MVC revisited

  - by Rick Strahl

  Last year I posted a detailed article on how to render Razor Views to string both inside of ASP.NET MVC and outside of it. In that article I showed several different approaches to capture the rendering output. The first and easiest is to use an existing MVC Controller Context to render a view by simply passing the controller context which is fairly trivial and I demonstrated a simple ViewRenderer class that simplified the process down to a couple lines of code. However, if no Controller Context is available the process is not quite as straight forward and I referenced an old, much more complex example that uses my RazorHosting library, which is a custom self-contained implementation of the Razor templating engine that can be hosted completely outside of ASP.NET. While it works inside of ASP.NET, it’s an awkward solution when running inside of ASP.NET, because it requires a bit of setup to run efficiently.Well, it turns out that I missed something in the original article, namely that it is possible to create a ControllerContext, if you have a controller instance, even if MVC didn’t create that instance. Creating a Controller Instance outside of MVCThe trick to make this work is to create an MVC Controller instance – any Controller instance – and then configure a ControllerContext through that instance. As long as an HttpContext.Current is available it’s possible to create a fully functional controller context as Razor can get all the necessary context information from the HttpContextWrapper().The key to make this work is the following method:/// <summary> /// Creates an instance of an MVC controller from scratch /// when no existing ControllerContext is present /// </summary> /// <typeparam name="T">Type of the controller to create</typeparam> /// <returns>Controller Context for T</returns> /// <exception cref="InvalidOperationException">thrown if HttpContext not available</exception> public static T CreateController<T>(RouteData routeData = null) where T : Controller, new() { // create a disconnected controller instance T controller = new T(); // get context wrapper from HttpContext if available HttpContextBase wrapper = null; if (HttpContext.Current != null) wrapper = new HttpContextWrapper(System.Web.HttpContext.Current); else throw new InvalidOperationException( "Can't create Controller Context if no active HttpContext instance is available."); if (routeData == null) routeData = new RouteData(); // add the controller routing if not existing if (!routeData.Values.ContainsKey("controller") && !routeData.Values.ContainsKey("Controller")) routeData.Values.Add("controller", controller.GetType().Name .ToLower() .Replace("controller", "")); controller.ControllerContext = new ControllerContext(wrapper, routeData, controller); return controller; }This method creates an instance of a Controller class from an existing HttpContext which means this code should work from anywhere within ASP.NET to create a controller instance that’s ready to be rendered. This means you can use this from within an Application_Error handler as I needed to or even from within a WebAPI controller as long as it’s running inside of ASP.NET (ie. not self-hosted). Nice.So using the ViewRenderer class from the previous article I can now very easily render an MVC view outside of the context of MVC. Here’s what I ended up in my Application’s custom error HttpModule: protected override void OnDisplayError(WebErrorHandler errorHandler, ErrorViewModel model) { var Response = HttpContext.Current.Response; Response.ContentType = "text/html"; Response.StatusCode = errorHandler.OriginalHttpStatusCode; var context = ViewRenderer.CreateController<ErrorController>().ControllerContext; var renderer = new ViewRenderer(context); string html = renderer.RenderView("~/Views/Shared/GenericError.cshtml", model); Response.Write(html); }That’s pretty sweet, because it’s now possible to use ViewRenderer just about anywhere in any ASP.NET application, not only inside of controller code. This also allows the constructor for the ViewRenderer from the last article to work without a controller context parameter, using a generic view as a base for the controller context when not passed:public ViewRenderer(ControllerContext controllerContext = null) { // Create a known controller from HttpContext if no context is passed if (controllerContext == null) { if (HttpContext.Current != null) controllerContext = CreateController<ErrorController>().ControllerContext; else throw new InvalidOperationException( "ViewRenderer must run in the context of an ASP.NET " + "Application and requires HttpContext.Current to be present."); } Context = controllerContext; }In this case I use the ErrorController class which is a generic controller instance that exists in the same assembly as my ViewRenderer class and that works just fine since ‘generically’ rendered views tend to not rely on anything from the controller other than the model which is explicitly passed.While these days most of my apps use MVC I do still have a number of generic pieces in most of these applications where Razor comes in handy. This includes modules like the above, which when they error often need to display error output. In other cases I need to generate string template output for emailing or logging data to disk. Being able to render simply render an arbitrary View to and pass in a model makes this super nice and easy at least within the context of an ASP.NET application!You can check out the updated ViewRenderer class below to render your ‘generic views’ from anywhere within your ASP.NET applications. Hope some of you find this useful.ResourcesViewRenderer Class in Westwind.Web.Mvc Library (Github)Original ViewRenderer ArticleRazor Hosting Library (GitHub)Original Razor Hosting Article© Rick Strahl, West Wind Technologies, 2005-2013Posted in ASP.NET  MVC   Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

  Read the article

• Accessing ImageButton Contents

  - by Bill

  I am representing a Solar-System's planets with ImageButtons that show the planet's image on the surface of the button, and hold the planet's important data.. name, distance from sun, etc within an instance of a Planet class, stored within the ImageButton.Content property. When the ImageButton is selected, I am attempting to access and display the Planet class's data for the selected Planet. Although ((ImageButton)e.OriginalSource).Content permits viewing all of the Planet class's properties in the debugger, I haven't figured out how to access the Planet class properties directly, as in Pluto.DistanceFromTheSun? Is it possible to access the Planet class information held in the ImageButton contents directly?

  Read the article

• printing in the same line in java.

  - by sil3nt

  Hi there, I have a base class called Items and 3 derived classes, and within the Items base class i have a print function of the form public void print(){ System.out.println("ID " + id + " Title " + title + " <" + year + "> "); } and within every derived class I call the Items print function through super.print(); which is followed by a specific print function relating to the derived class. My problem is, whenever the printing is executed from one of the derived classes the printed text is not on the same line. So super.print() will be in the line above the derived class print function. How do I get them both to be on the same line?

  Read the article

• python metaprogramming

  - by valya

  I'm trying to archive a task which turns out to be a bit complicated since I'm not very good at Python metaprogramming. I want to have a module locations with function get_location(name), which returns a class defined in a folder locations/ in the file with the name passed to function. Name of a class is something like NameLocation. So, my folder structure: program.py locations/ __init__.py first.py second.py program.py will be smth with with: from locations import get_location location = get_location('first') and the location is a class defined in first.py smth like this: from locations import Location # base class for all locations, defined in __init__ (?) class FirstLocation(Location): pass etc. Okay, I've tried a lot of import and getattribute statements but now I'm bored and surrender. How to archive such behaviour?

  Read the article

• Algorithmia Source Code released on CodePlex

  - by FransBouma

  Following the release of our BCL Extensions Library on CodePlex, we have now released the source-code of Algorithmia on CodePlex! Algorithmia is an algorithm and data-structures library for .NET 3.5 or higher and is one of the pillars LLBLGen Pro v3's designer is built on. The library contains many data-structures and algorithms, and the source-code is well documented and commented, often with links to official descriptions and papers of the algorithms and data-structures implemented. The source-code is shared using Mercurial on CodePlex and is licensed under the friendly BSD2 license. User documentation is not available at the moment but will be added soon. One of the main design goals of Algorithmia was to create a library which contains implementations of well-known algorithms which weren't already implemented in .NET itself. This way, more developers out there can enjoy the results of many years of what the field of Computer Science research has delivered. Some algorithms and datastructures are known in .NET but are re-implemented because the implementation in .NET isn't efficient for many situations or lacks features. An example is the linked list in .NET: it doesn't have an O(1) concat operation, as every node refers to the containing LinkedList object it's stored in. This is bad for algorithms which rely on O(1) concat operations, like the Fibonacci heap implementation in Algorithmia. Algorithmia therefore contains a linked list with an O(1) concat feature. The following functionality is available in Algorithmia: Command, Command management. This system is usable to build a fully undo/redo aware system by building your object graph using command-aware classes. The Command pattern is implemented using a system which allows transparent undo-redo and command grouping so you can use it to make a class undo/redo aware and set properties, use its contents without using commands at all. The Commands namespace is the namespace to start. Classes you'd want to look at are CommandifiedMember, CommandifiedList and KeyedCommandifiedList. See the CommandQueueTests in the test project for examples. Graphs, Graph algorithms. Algorithmia contains a sophisticated graph class hierarchy and algorithms implemented onto them: non-directed and directed graphs, as well as a subgraph view class, which can be used to create a view onto an existing graph class which can be self-maintaining. Algorithms include transitive closure, topological sorting and others. A feature rich depth-first search (DFS) crawler is available so DFS based algorithms can be implemented quickly. All graph classes are undo/redo aware, as they can be set to be 'commandified'. When a graph is 'commandified' it will do its housekeeping through commands, which makes it fully undo-redo aware, so you can remove, add and manipulate the graph and undo/redo the activity automatically without any extra code. If you define the properties of the class you set as the vertex type using CommandifiedMember, you can manipulate the properties of vertices and the graph contents with full undo/redo functionality without any extra code. Heaps. Heaps are data-structures which have the largest or smallest item stored in them always as the 'root'. Extracting the root from the heap makes the heap determine the next in line to be the 'maximum' or 'minimum' (max-heap vs. min-heap, all heaps in Algorithmia can do both). Algorithmia contains various heaps, among them an implementation of the Fibonacci heap, one of the most efficient heap datastructures known today, especially when you want to merge different instances into one. Priority queues. Priority queues are specializations of heaps. Algorithmia contains a couple of them. Sorting. What's an algorithm library without sort algorithms? Algorithmia implements a couple of sort algorithms which sort the data in-place. This aspect is important in situations where you want to sort the elements in a buffer/list/ICollection in-place, so all data stays in the data-structure it already is stored in. PropertyBag. It re-implements Tony Allowatt's original idea in .NET 3.5 specific syntax, which is to have a generic property bag and to be able to build an object in code at runtime which can be bound to a property grid for editing. This is handy for when you have data / settings stored in XML or other format, and want to create an editable form of it without creating many editors. IEditableObject/IDataErrorInfo implementations. It contains default implementations for IEditableObject and IDataErrorInfo (EditableObjectDataContainer for IEditableObject and ErrorContainer for IDataErrorInfo), which make it very easy to implement these interfaces (just a few lines of code) without having to worry about bookkeeping during databinding. They work seamlessly with CommandifiedMember as well, so your undo/redo aware code can use them out of the box. EventThrottler. It contains an event throttler, which can be used to filter out duplicate events in an event stream coming into an observer from an event. This can greatly enhance performance in your UI without needing to do anything other than hooking it up so it's placed between the event source and your real handler. If your UI is flooded with events from data-structures observed by your UI or a middle tier, you can use this class to filter out duplicates to avoid redundant updates to UI elements or to avoid having observers choke on many redundant events. Small, handy stuff. A MultiValueDictionary, which can store multiple unique values per key, instead of one with the default Dictionary, and is also merge-aware so you can merge two into one. A Pair class, to quickly group two elements together. Multiple interfaces for helping with building a de-coupled, observer based system, and some utility extension methods for the defined data-structures. We regularly update the library with new code. If you have ideas for new algorithms or want to share your contribution, feel free to discuss it on the project's Discussions page or send us a pull request. Enjoy!

  Read the article

• Using NHibernate Criteria API to select sepcific set of data together with a count

  - by mfloryan

  I have the following domain set up for persistence with NHibernate: I am using the PaperConfiguration as the root aggregate. I want to select all PaperConfiguration objects for a given Tier and AcademicYearConfiguration. This works really well as per the following example: ICriteria criteria = session.CreateCriteria<PaperConfiguration>() .Add(Restrictions.Eq("AcademicYearConfiguration", configuration)) .CreateCriteria("Paper") .CreateCriteria("Unit") .CreateCriteria("Tier") .Add(Restrictions.Eq("Id", tier.Id)) return criteria.List<PaperConfiguration>(); (Perhaps there is a better way of doing this though). Yet also need to know how many ReferenceMaterials there are for each PaperConfiguration and I would like to get it in the same call. Avoid HQL - I already have an HQL solution for it. I know this is what projections are for and this question suggests an idea but I can't get it to work. I have a PaperConfigurationView that has, instead of IList<ReferenceMaterial> ReferenceMaterials the ReferenceMaterialCount and was thinking along the lines of ICriteria criteria = session.CreateCriteria<PaperConfiguration>() .Add(Restrictions.Eq("AcademicYearConfiguration", configuration)) .CreateCriteria("Paper") .CreateCriteria("Unit") .CreateCriteria("Tier") .Add(Restrictions.Eq("Id", tier.Id)) .SetProjection( Projections.ProjectionList() .Add(Projections.Property("IsSelected"), "IsSelected") .Add(Projections.Property("Paper"), "Paper") // and so on for all relevant properties .Add(Projections.Count("ReferenceMaterials"), "ReferenceMaterialCount") .SetResultTransformer(Transformers.AliasToBean<PaperConfigurationView>()); return criteria.List< PaperConfigurationView >(); unfortunately this does not work. What am I doing wrong? The following simplified query: ICriteria criteria = session.CreateCriteria<PaperConfiguration>() .CreateCriteria("ReferenceMaterials") .SetProjection( Projections.ProjectionList() .Add(Projections.Property("Id"), "Id") .Add(Projections.Count("ReferenceMaterials"), "ReferenceMaterialCount") ).SetResultTransformer(Transformers.AliasToBean<PaperConfigurationView>()); return criteria.List< PaperConfigurationView >(); creates this rather unexpected SQL: SELECT this_.Id as y0_, count(this_.Id) as y1_ FROM Domain.PaperConfiguration this_ inner join Domain.ReferenceMaterial referencem1_ on this_.Id=referencem1_.PaperConfigurationId The above query fails with ADO.NET error as it obviously is not a correct SQL since it is missing a group by or the count being count(referencem1_.Id) rather than (this_.Id). NHibernate mappings: <class name="PaperConfiguration" table="PaperConfiguration"> <id name="Id" type="Int32"> <column name="Id" sql-type="int" not-null="true" unique="true" index="PK_PaperConfiguration"/> <generator class="native" /> </id> <!-- IPersistent --> <version name="VersionLock" /> <!-- IAuditable --> <property name="WhenCreated" type="DateTime" /> <property name="CreatedBy" type="String" length="50" /> <property name="WhenChanged" type="DateTime" /> <property name="ChangedBy" type="String" length="50" /> <property name="IsEmeEnabled" type="boolean" not-null="true" /> <property name="IsSelected" type="boolean" not-null="true" /> <many-to-one name="Paper" column="PaperId" class="Paper" not-null="true" access="field.camelcase"/> <many-to-one name="AcademicYearConfiguration" column="AcademicYearConfigurationId" class="AcademicYearConfiguration" not-null="true" access="field.camelcase"/> <bag name="ReferenceMaterials" generic="true" cascade="delete" lazy="true" inverse="true"> <key column="PaperConfigurationId" not-null="true" /> <one-to-many class="ReferenceMaterial" /> </bag> </class> <class name="ReferenceMaterial" table="ReferenceMaterial"> <id name="Id" type="Int32"> <column name="Id" sql-type="int" not-null="true" unique="true" index="PK_ReferenceMaterial"/> <generator class="native" /> </id> <!-- IPersistent --> <version name="VersionLock" /> <!-- IAuditable --> <property name="WhenCreated" type="DateTime" /> <property name="CreatedBy" type="String" length="50" /> <property name="WhenChanged" type="DateTime" /> <property name="ChangedBy" type="String" length="50" /> <property name="Name" type="String" not-null="true" /> <property name="ContentFile" type="String" not-null="false" /> <property name="Position" type="int" not-null="false" /> <property name="CommentaryName" type="String" not-null="false" /> <property name="CommentarySubjectTask" type="String" not-null="false" /> <property name="CommentaryPointScore" type="String" not-null="false" /> <property name="CommentaryContentFile" type="String" not-null="false" /> <many-to-one name="PaperConfiguration" column="PaperConfigurationId" class="PaperConfiguration" not-null="true"/> </class>

  Read the article

• OperationalError "unable to open database file" processing query results with SQLAlchemy and SQLite3

  - by Peter

  I'm running into this little problem that I hope is just a dumb user error. It looks like some sort of a size limit with a query to a SQLite database. I managed to reproduce the issue with an in-memory DB and a simple script shown below. I can make it work by either reducing the number of records in the DB; or by reducing the size of each record; or by dropping the order_by() call. I am using Python 2.5.5 and SQLAlchemy 0.6.0 in a Cygwin environment. Thanks! #!/usr/bin/python from sqlalchemy.orm import sessionmaker import sqlalchemy import sqlalchemy.orm class Person(object): def __init__(self, name): self.name = name engine = sqlalchemy.create_engine('sqlite:///:memory:') Session = sessionmaker(bind=engine) metadata = sqlalchemy.schema.MetaData(bind=engine) person_table = sqlalchemy.Table('person', metadata, sqlalchemy.Column('id', sqlalchemy.types.Integer, primary_key=True), sqlalchemy.Column('name', sqlalchemy.types.String)) metadata.create_all(engine) sqlalchemy.orm.mapper(Person, person_table) session = Session() session.add_all([Person("012345678901234567890123456789012") for i in range(5000)]) session.commit() persons = session.query(Person).order_by(Person.name).all() print "count =", len(persons) session.close() The all() call to the query result fails with the OperationalError exception: Traceback (most recent call last): File "./stress.py", line 27, in <module> persons = session.query(Person).order_by(Person.name).all() File "/usr/lib/python2.5/site-packages/sqlalchemy/orm/query.py", line 1343, in all return list(self) File "/usr/lib/python2.5/site-packages/sqlalchemy/orm/query.py", line 1451, in __iter__ return self._execute_and_instances(context) File "/usr/lib/python2.5/site-packages/sqlalchemy/orm/query.py", line 1456, in _execute_and_instances mapper=self._mapper_zero_or_none()) File "/usr/lib/python2.5/site-packages/sqlalchemy/orm/session.py", line 737, in execute clause, params or {}) File "/usr/lib/python2.5/site-packages/sqlalchemy/engine/base.py", line 1109, in execute return Connection.executors[c](self, object, multiparams, params) File "/usr/lib/python2.5/site-packages/sqlalchemy/engine/base.py", line 1186, in _execute_clauseelement return self.__execute_context(context) File "/usr/lib/python2.5/site-packages/sqlalchemy/engine/base.py", line 1215, in __execute_context context.parameters[0], context=context) File "/usr/lib/python2.5/site-packages/sqlalchemy/engine/base.py", line 1284, in _cursor_execute self._handle_dbapi_exception(e, statement, parameters, cursor, context) File "/usr/lib/python2.5/site-packages/sqlalchemy/engine/base.py", line 1282, in _cursor_execute self.dialect.do_execute(cursor, statement, parameters, context=context) File "/usr/lib/python2.5/site-packages/sqlalchemy/engine/default.py", line 277, in do_execute cursor.execute(statement, parameters) sqlalchemy.exc.OperationalError: (OperationalError) unable to open database file u'SELECT person.id AS person_id, person.name AS person_name \nFROM person ORDER BY person.name' ()

  Read the article

• NHibernate Many-To-One on Joined Sublcass with Filter

  - by Nathan Roe

  I have a class setup that looks something like this: public abstract class Parent { public virtual bool IsDeleted { get; set; } } public class Child : Parent { } public class Other { public virtual ICollection<Child> Children { get; set; } } Child is mapped as a joined-subclass of Parent. Childen is mapped as a Many-To-One bag. The bag has a filter applied to it named SoftDeletableFilter. The filter mapping looks like: <filter-def name="SoftDeleteableFilter" condition="(IsDeleted = 0 or IsDeleted is null)" /> That problem is that when Other.Children is loaded the filter is being applied to the Child table and not the parent table. Is there any way to tell NHibernate to apply the filter to the parent class?

  Read the article

• Dolphin Smalltalk - adding method

  - by bialpio

  Hi, I am trying to create a custom class in Dolphin Smalltalk. When I open the Workspace, type in and evaluate the code: Object subclass: #Sudoku instanceVariableNames: 'board' classVariableNames: '' poolDictionaries: '' category: 'JiPP SudokuSolver'. everything works fine and the class is created and visible from Class Browser. The problem is, I want to add custom member method to this class, but without using Class Browser. Is it possible from the Workspace? I want to have one file with all the source code, so I don't have to worry about saving entire image.

  Read the article

• Loading, listing, and using R Modules and Functions in PL/R

  - by Dave Jarvis

  I am having difficulty with: Listing the R packages and functions available to PostgreSQL. Installing a package (such as Kendall) for use with PL/R Calling an R function within PostgreSQL Listing Available R Packages Q.1. How do you find out what R modules have been loaded? SELECT * FROM r_typenames(); That shows the types that are available, but what about checking if Kendall( X, Y ) is loaded? For example, the documentation shows: CREATE TABLE plr_modules ( modseq int4, modsrc text ); That seems to allow inserting records to dictate that Kendall is to be loaded, but the following code doesn't explain, syntactically, how to ensure that it gets loaded: INSERT INTO plr_modules VALUES (0, 'pg.test.module.load <-function(msg) {print(msg)}'); Q.2. What would the above line look like if you were trying to load Kendall? Q.3. Is it applicable? Installing R Packages Using the "synaptic" package manager the following packages have been installed: r-base r-base-core r-base-dev r-base-html r-base-latex r-cran-acepack r-cran-boot r-cran-car r-cran-chron r-cran-cluster r-cran-codetools r-cran-design r-cran-foreign r-cran-hmisc r-cran-kernsmooth r-cran-lattice r-cran-matrix r-cran-mgcv r-cran-nlme r-cran-quadprog r-cran-robustbase r-cran-rpart r-cran-survival r-cran-vr r-recommended Q.4. How do I know if Kendall is in there? Q.5. If it isn't, how do I find out what package it is in? Q.6. If it isn't in a package suitable for installing with apt-get (aptitude, synaptic, dpkg, what have you), how do I go about installing it on Ubuntu? Q.7. Where are the installation steps documented? Calling R Functions I have the following code: EXECUTE 'SELECT ' 'regr_slope( amount, year_taken ),' 'regr_intercept( amount, year_taken ),' 'corr( amount, year_taken ),' 'sum( measurements ) AS total_measurements ' 'FROM temp_regression' INTO STRICT slope, intercept, correlation, total_measurements; This code calls the PostgreSQL function corr to calculate Pearson's correlation over the data. Ideally, I'd like to do the following (by switching corr for plr_kendall): EXECUTE 'SELECT ' 'regr_slope( amount, year_taken ),' 'regr_intercept( amount, year_taken ),' 'plr_kendall( amount, year_taken ),' 'sum( measurements ) AS total_measurements ' 'FROM temp_regression' INTO STRICT slope, intercept, correlation, total_measurements; Q.8. Do I have to write plr_kendall myself? Q.9. Where can I find a simple example that walks through: Loading an R module into PG. Writing a PG wrapper for the desired R function. Calling the PG wrapper from a SELECT. For example, would the last two steps look like: create or replace function plr_kendall( _float8, _float8 ) returns float as ' agg_kendall(arg1, arg2) ' language 'plr'; CREATE AGGREGATE agg_kendall ( sfunc = plr_array_accum, basetype = float8, -- ??? stype = _float8, -- ??? finalfunc = plr_kendall ); And then the SELECT as above? Thank you!

  Read the article

< Previous Page | 350 351 352 353 354 355 356 357 358 359 360 361  | Next Page >