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  • A Django form for entering a 0 to n email addresses

    - by Erik
    I have a Django application with some fairly common models in it: UserProfile and Organization. A UserProfile or an Organization can both have 0 to n emails, so I have an Email model that has a GenericForeignKey. UserProfile and Organization Models both have a GenericRelation called emails that points back to the Email model (summary code provided below). The question: what is the best way to provide an Organization form that allows a user to enter organization details including 0 to n email addresses? My Organization create view is a Django class-based view. I'm leading towards creating a dynamic form and an enabling it with Javascript to allow the user to add as many email addresses as necessary. I will render the form with django-crispy-forms. I've thought about doing this with a formset embedded within the form, but this seems like overkill for email addresses. Embedding a formset in a form delivered by a class-based view is cumbersome too. Note that the same issue occurs with the Organization fields phone_numbers and locations. emails.py: from django.db import models from parent_mixins import Parent_Mixin class Email(Parent_Mixin,models.Model): email_type = models.CharField(blank=True,max_length=100,null=True,default=None,verbose_name='Email Type') email = models.EmailField() class Meta: app_label = 'core' organizations.py: from emails import Email from locations import Location from phone_numbers import Phone_Number from django.contrib.contenttypes import generic from django.db import models class Organization(models.Model): active = models.BooleanField() duns_number = models.CharField(blank=True,default=None,null=True,max_length=9) # need to validate this emails = generic.GenericRelation(Email,content_type_field='parent_type',object_id_field='parent_id') legal_name = models.CharField(blank=True,default=None,null=True,max_length=200) locations = generic.GenericRelation(Location,content_type_field='parent_type',object_id_field='parent_id') name = models.CharField(blank=True,default=None,null=True,max_length=200) organization_group = models.CharField(blank=True,default=None,null=True,max_length=200) organization_type = models.CharField(blank=True,default=None,null=True,max_length=200) phone_numbers = generic.GenericRelation(Phone_Number,content_type_field='parent_type',object_id_field='parent_id') taxpayer_id_number = models.CharField(blank=True,default=None,null=True,max_length=9) # need to validate this class Meta: app_label = 'core' parent_mixins.py from django.contrib.contenttypes.models import ContentType from django.contrib.contenttypes import generic from django.db import models class Parent_Mixin(models.Model): parent_type = models.ForeignKey(ContentType,blank=True,null=True) parent_id = models.PositiveIntegerField(blank=True,null=True) parent = generic.GenericForeignKey('parent_type', 'parent_id') class Meta: abstract = True app_label = 'core'

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  • IoC & Interfaces Best Practices

    - by n8wrl
    I'm experimenting with IoC on my way to TDD by fiddling with an existing project. In a nutshell, my question is this: what are the best practices around IoC when public and non-public methods are of interest? There are two classes: public abstract class ThisThingBase { public virtual void Method1() {} public virtual void Method2() {} public ThatThing GetThat() { return new ThatThing(this); } internal virtual void Method3() {} internal virtual void Method4() {} } public class Thathing { public ThatThing(ThisThingBase thing) { m_thing = thing; } ... } ThatThing does some stuff using its ThisThingBase reference to call methods that are often overloaded by descendents of ThisThingBase. Method1 and Method2 are public. Method3 and Method4 are internal and only used by ThatThings. I would like to test ThatThing without ThisThing and vice-versa. Studying up on IoC my first thought was that I should define an IThing interface, implement it by ThisThingBase and pass it to the ThatThing constructor. IThing would be the public interface clients could call but it doesn't include Method3 or Method4 that ThatThing also needs. Should I define a 2nd interface - IThingInternal maybe - for those two methods and pass BOTH interfaces to ThatThing?

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  • Deserializing a FileStream on Client using WCF

    - by Grandpappy
    I'm very new to WCF, so I apologize in advance if I misstate something. This is using .NET 4.0 RC1. Using WCF, I am trying to deserialize a response from the server. The base response has a Stream as its only MessageBodyMember. public abstract class StreamedResponse { [MessageBodyMember] public Stream Stream { get; set; } public StreamedResponse() { this.Stream = Stream.Null; } } The derived versions of this class are actually what's serialized, but they don't have a MessageBodyMember attribute (they have other base types such as int, string, etc listed as MessageHeader values). [MessageContract] public class ChildResponse : StreamedResponse { [DataMember] [MessageHeader] public Guid ID { get; set; } [DataMember] [MessageHeader] public string FileName { get; set; } [DataMember] [MessageHeader] public long FileSize { get; set; } public ChildResponse() : base() { } } The Stream is always a FileStream, in my specific case (but may not always be). At first, WCF said FileStream was not a known type, so I added it to the list of known types and now it serializes. It also appears, at first glance, to deserialize it on the client's side (it's the FileStream type). The problem is that it doesn't seem to be usable. All the CanRead, CanWrite, etc are false, and the Length, Position, etc properties throw exceptions when being used. Same with ReadByte(). What am I missing that would keep me from getting a valid FileStream?

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  • How to pass binary data between two apps using Content Provider?

    - by Viktor
    I need to pass some binary data between two android apps using Content Provider (sharedUserId is not an option). I would prefer not to pass the data (a savegame stored as a file, small in size < 20k) as a file (ie. overriding openFile()) since this would necessitate some complicated temp-file scheme to cope with concurrency with several content provider accesses and a running game. I would like to read the file into memory under a mutex lock and then pass the binary array in the simplest way possible. How do I do this? It seems creating a file in memory is not a possibility due to the return type of openFile(). query() needs to return a Cursor. Using MatrixCursor is not possible since it applies toString() to all stored objects when reading it. What do I need to do? Implement a custom Cursor? This class has 30 abstract methods. Do I read the file, put it in a SQLite db and return the cursor? The complexity of this seemingly simple task is mindboggling.

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  • Typecasting EnityObject

    - by AJ
    Hello, I'm new to C# and am stuck on the following. I have a Silverlight web service that uses LINQ to query a ADO.NET entity object. e.g.: [OperationContract] public List<Customer> GetData() { using (TestEntities ctx = new TestEntities()) { var data = from rec in ctx.Customer select rec; return data.ToList(); } } This works fine, but what I want to do is to make this more abstract. The first step would be to return a List<EntityObject> but this gives a compiler error, e.g.: [OperationContract] public List<EntityObject> GetData() { using (TestEntities ctx = new TestEntities()) { var data = from rec in ctx.Customer select rec; return data.ToList(); } } The error is: Error 1 Cannot implicitly convert type 'System.Collections.Generic.List<SilverlightTest.Web.Customer>' to 'System.Collections.Generic.IEnumerable<System.Data.Objects.DataClasses.EntityObject>'. An explicit conversion exists (are you missing a cast?) What am i doing wrong? Thanks, AJ

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  • How to not pass around the container when using IoC in Winforms

    - by L2Type
    I'm new to the world of IoC and having a problem with implementing it in a Winforms application. I have an extremely basic application Winform application that uses MVC, it is one controller that does all the work and a working dialog (obviously with a controller). So I load all my classes in to my IoC container in program.cs and create the main form controller using the container. But this is where I am having problems, I only want to create the working dialog controller when it's used and inside a using statement. At first I passed in the container but I've read this is bad practice and more over the container is a static and I want to unit test this class. So how do you create classes in a unit test friendly way without passing in the container, I was considering the abstract factory pattern but that alone would solve my problem without using the IoC. I'm not using any famous framework, I borrowed a basic one from this blog post http://www.kenegozi.com/Blog/2008/01/17/its-my-turn-to-build-an-ioc-container-in-15-minutes-and-33-lines.aspx How do I do this with IoC? Is this the wrong use for IoC?

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  • Threadsafe binding with DispatcherObject.CheckAccess()

    - by maffe
    Hi, according to this, I can achieve threadsafety with large overhead. I wrote the following class and use it. It works fine. public abstract class BindingBase : DispatcherObject, INotifyPropertyChanged, INotifyPropertyChanging { private string _displayName; private const string NameDisplayName = "DisplayName"; /// /// The display name for the gui element which bound this instance. It can be used for localization. /// public string DisplayName { get { return _displayName; } set { NotifyPropertyChanging(NameDisplayName); _displayName = value; NotifyPropertyChanged(NameDisplayName); } } protected BindingBase() {} protected BindingBase(string displayName) { DisplayName = displayName; } public event PropertyChangedEventHandler PropertyChanged; public event PropertyChangingEventHandler PropertyChanging; protected void NotifyPropertyChanged(string name) { if (PropertyChanged == null) return; if (CheckAccess()) PropertyChanged.Invoke(this, new PropertyChangedEventArgs(name)); else Dispatcher.BeginInvoke(DispatcherPriority.Normal, (Action) (() = NotifyPropertyChanged(name))); } protected void NotifyPropertyChanging(string name) { if (PropertyChanging == null) return; if (CheckAccess()) PropertyChanging.Invoke(this, new PropertyChangingEventArgs(name)); else Dispatcher.BeginInvoke(DispatcherPriority.Normal, (Action) (() = NotifyPropertyChanging(name))); } } So is there a reason, why I've never found something like that? Are there any issues I should be aware off? Regards

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  • Extend base type and automatically update audit information on Entity

    - by Nix
    I have an entity model that has audit information on every table (50+ tables) CreateDate CreateUser UpdateDate UpdateUser Currently we are programatically updating audit information. Ex: if(changed){ entity.UpdatedOn = DateTime.Now; entity.UpdatedBy = Environment.UserName; context.SaveChanges(); } But I am looking for a more automated solution. During save changes, if an entity is created/updated I would like to automatically update these fields before sending them to the database for storage. Any suggestion on how i could do this? I would prefer to not do any reflection, so using a text template is not out of the question. A solution has been proposed to override SaveChanges and do it there, but in order to achieve this i would either have to use reflection (in which I don't want to do ) or derive a base class. Assuming i go down this route how would I achieve this? For example EXAMPLE_DB_TABLE CODE NAME --Audit Tables CREATE_DATE CREATE_USER UPDATE_DATE UPDATE_USER And if i create a base class public abstract class IUpdatable{ public virtual DateTime CreateDate {set;} public virtual string CreateUser { set;} public virtual DateTime UpdateDate { set;} public virtual string UpdateUser { set;} } The end goal is to be able to do something like... public overrride void SaveChanges(){ //Go through state manager and update audit infromation //FOREACH changed entity in state manager if(entity is IUpdatable){ //If state is created... update create audit. //if state is updated... update update audit } } But I am not sure how I go about generating the code that would extend the interface.

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  • How to use a Spring config file in a Maven dependency

    - by javamonkey79
    In dependency A I have the following: <beans> <bean id="simplePersonBase" class="com.paml.test.SimplePerson" abstract="true"> <property name="firstName" value="Joe" /> <property name="lastName" value="Smith" /> </bean> </beans> And then in project B, I add A as a dependency and have the following config: <?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.xsd"> <bean id="simplePersonAddress01" parent="simplePersonBase"> <property name="firstName" value="BillyBob" /> <property name="address" value="1060 W. Addison St" /> <property name="city" value="Chicago" /> <property name="state" value="IL" /> <property name="zip" value="60613" /> </bean> </beans> When I use ClassPathXmlApplicationContext like so: BeanFactory beanFactory = new ClassPathXmlApplicationContext( new String[] { "./*.xml" } ); SimplePerson person = (SimplePerson)beanFactory.getBean( "simplePersonAddress01" ); System.out.println( person.getFirstName() ); Spring complains as it can not resolve the parent xml. Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'simplePersonBase' is defined I am sure there is a way to do this, however, I have not found it. Does anyone know how?

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  • WPF Designer has bug with parsing generic control with overrided property

    - by Ivan Laktyunkin
    I've created a generic lookless control with virtual property: public abstract class TestControlBase<TValue> : Control { public static readonly DependencyProperty ValueProperty; static TestControlBase() { ValueProperty = DependencyProperty.Register("Value", typeof(TValue), typeof(TestControlBase<TValue>)); } protected TestControlBase() { Focusable = false; Value = default(TValue); } public virtual TValue Value { get { return (TValue)GetValue(ValueProperty); } set { SetValue(ValueProperty, value); } } } Then I've made a control derived from it and overrided Value property: public class TestControl : TestControlBase<int> { public override int Value { get { return base.Value; } set { base.Value = value; } } } So I use it in a Window XAML: <TestControls:TestControl /> When I open window in designer all is OK, but when I put mouse cursor to this line, or to this control in designer I receive exception: Exception has been thrown by the target of an invocation. at System.RuntimeMethodHandle._InvokeMethodFast(Object target, Object[] arguments, SignatureStruct& sig, MethodAttributes methodAttributes, RuntimeTypeHandle typeOwner) at System.RuntimeMethodHandle.InvokeMethodFast(Object target, Object[] arguments, Signature sig, MethodAttributes methodAttributes, RuntimeTypeHandle typeOwner) at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture, Boolean skipVisibilityChecks) at System.Delegate.DynamicInvokeImpl(Object[] args) at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Boolean isSingleParameter) at System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Boolean isSingleParameter, Delegate catchHandler) Ambiguous match found. at System.RuntimeType.GetPropertyImpl(String name, BindingFlags bindingAttr, Binder binder, Type returnType, Type[] types, ParameterModifier[] modifiers) at System.Type.GetProperty(String name) at MS.Internal.ComponentModel.DependencyPropertyKind.get_IsDirect() at MS.Internal.ComponentModel.DependencyPropertyKind.get_IsAttached() at MS.Internal.ComponentModel.APCustomTypeDescriptor.GetProperties(Attribute[] attributes) at MS.Internal.ComponentModel.APCustomTypeDescriptor.GetProperties() at System.ComponentModel.TypeDescriptor.TypeDescriptionNode.DefaultExtendedTypeDescriptor.System.ComponentModel.ICustomTypeDescriptor.GetProperties() at System.ComponentModel.TypeDescriptor.GetPropertiesImpl(Object component, Attribute[] attributes, Boolean noCustomTypeDesc, Boolean noAttributes) at System.ComponentModel.TypeDescriptor.GetProperties(Object component) at MS.Internal.Model.ModelPropertyCollectionImpl.GetProperties(String propertyNameHint) at MS.Internal.Model.ModelPropertyCollectionImpl.<GetEnumerator>d__0.MoveNext() at MS.Internal.Designer.PropertyEditing.Model.ModelPropertyMerger.<GetFirstProperties>d__0.MoveNext() at MS.Internal.Designer.PropertyEditing.PropertyInspector.UpdateCategories(Selection selection) at MS.Internal.Designer.PropertyEditing.PropertyInspector.OnSelectionChangedIdle() Who know this problem? Please explain :) I have no ideas except that WPF Designer doesn't like generics. If I replace generics by Object all is OK.

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  • using Autofac in a multi-layered architecture

    - by Kamyar
    I'm fairly new to the DI/IoC concept and would like to use Autofac in a 3-layered ASP.NET Webforms application. UI layer: An ASP.NET webforms website. BLL: Business logic layer which calls the repositories on DAL. DAL: .EDMX file (Entity Model) and ObjectContext with Repository classes which abstract the CRUD operations for each entity. Entities: The POCO Entities. Persistence Ignorant. Generated by Microsoft's ADO.Net POCO Entity Generator. I have asked a more general question here. Basically, I'd like to create an obejctcontext per HttpContext in my DAL. But i don't want to add a reference to DAL in UI or access to HttpContext in DAL directly. I guess this is where IoC tools come to play. The answer to my previous question is a very good example of using Windsor Castle. I'd like to use Autofac as my IoC tool and Don't know how to achieve this. (How to access DAL in application_start to register the component while I don't want to reference it in my UI, what are the proper references to be able to use DAL component in BLL with Autofac, Should I register BLL as a component with Autofac too) Sorry folks for not providing an explicit question and requesting a kind of working example, But I'm very unfamiliar to the whole IoC concept and I don't think I can achieve it to use in my current time-limited project.

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  • Sweave/R - Automatically generating an appendix that contains all the model summaries/plots/data pro

    - by John Horton
    I like the idea of making research available at multiple levels of detail i.e., abstract for the casually curious, full text for the more interested, and finally the data and code for those working in the same area/trying to reproduce your results. In between the actual text and the data/code level, I'd like to insert another layer. Namely, I'd like to create a kind of automatically generated appendix that contains the full regression output, diagnostic plots, exploratory graphs data profiles etc. from the analysis, regardless of whether those plots/regressions etc. made it into the final paper. One idea I had was to write a script that would examine the .Rnw file and automatically: Profile all data sets that are loaded (sort of like the Hmisc(?) package) Summarize all regressions - i.e., run summary(model) for all models Present all plots (regardless of whether they made it in the final version) The idea is to make this kind of a low-effort, push-button sort of thing as opposed to a formal appendix written like the rest of a paper. What I'm looking for is some ideas on how to do this in R in a relatively simple way. My hunch is that there is some way of going through the namespace, figuring out what something is and then dumping into a PDF. Thoughts? Does something like this already exist?

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  • FileNotFoundException, although the XML file should be deployed

    - by Bernhard V
    Hi, I've got problems starting my WAR application on a local JBoss. After two other EARs are deployed and the TomcatDeployer begins deploying the WAR, I'm getting the following error message: 2010-04-28 10:01:56,605 ERROR [org.jboss.ejb.plugins.LogInterceptor] [] [main] EJBException in method: public abstract at.sozvers.stp.zpv.ejb.lea.rwsuc.EJBLeaRegelwerkSuchenRemote at.sozvers.stp.zpv.ejb.lea.rwsuc.EJBLeaRegelwerkSuchenHome.create() throws javax.ejb.CreateException,java.rmi.RemoteException, causedBy: javax.ejb.EJBException: org.springframework.beans.factory.access.BootstrapException: Unable to initialize group definition. Group resource name [classpath*:applicationContext.xml], factory key [contextService]; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'contextService' defined in URL [jar:file:/C:/ta30/nutzb/jboss-4.2.3.GA.ZPV/server/default/deploy/deploy.last/zpv-app-web-frontend-1.0-SNAPSHOT.war/WEB-INF/lib/zpv-comp-ejb-modules-1.0-SNAPSHOT-client.jar!/applicationContext.xml]: Instantiation of bean failed; nested exception is org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [org.springframework.context.support.ClassPathXmlApplicationContext]: Constructor threw exception; nested exception is org.springframework.beans.factory.BeanDefinitionStoreException: IOException parsing XML document from class path resource [at/sozvers/stp/zpv/dao/ContextBasic.xml]; nested exception is java.io.FileNotFoundException: class path resource [at/sozvers/stp/zpv/dao/ContextBasic.xml] cannot be opened because it does not exist The sad thing is that the resource at/sozvers/stp/zpv/dao/ContextBasic.xml actually is placed in a JAR in one of my EAR files which should be deployed before the WAR. And at least I get a message that the deployment of the EAR has been successful. I also looked into the JAR with my file archiver and the ContextBasic.xml is indeed there at the right place. Is there a way for me to get sure that the JAR, not the EAR as a whole, is really deployed to the JBoss? I'm already starting to lose my head about this issue. Thank you. Bernhard

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  • How do I correctly use Unity to pass a ConnectionString to my repository classes?

    - by GenericTypeTea
    I've literally just started using the Unity Application Blocks Dependency Injection library from Microsoft, and I've come unstuck. This is my IoC class that'll handle the instantiation of my concrete classes to their interface types (so I don't have to keep called Resolve on the IoC container each time I want a repository in my controller): public class IoC { public static void Intialise(UnityConfigurationSection section, string connectionString) { _connectionString = connectionString; _container = new UnityContainer(); section.Configure(_container); } private static IUnityContainer _container; private static string _connectionString; public static IMovementRepository MovementRepository { get { return _container.Resolve<IMovementRepository>(); } } } So, the idea is that from my Controller, I can just do the following: _repository = IoC.MovementRepository; I am currently getting the error: Exception is: InvalidOperationException - The type String cannot be constructed. You must configure the container to supply this value. Now, I'm assuming this is because my mapped concrete implementation requires a single string parameter for its constructor. The concrete class is as follows: public sealed class MovementRepository : Repository, IMovementRepository { public MovementRepository(string connectionString) : base(connectionString) { } } Which inherits from: public abstract class Repository { public Repository(string connectionString) { _connectionString = connectionString; } public virtual string ConnectionString { get { return _connectionString; } } private readonly string _connectionString; } Now, am I doing this the correct way? Should I not have a constructor in my concrete implementation of a loosely coupled type? I.e. should I remove the constructor and just make the ConnectionString property a Get/Set so I can do the following: public static IMovementRepository MovementRepository { get { return _container.Resolve<IMovementRepository>( new ParameterOverrides { { "ConnectionString", _connectionString } }.OnType<IMovementRepository>() ); } } So, I basically wish to know how to get my connection string to my concrete type in the correct way that matches the IoC rules and keeps my Controller and concrete repositories loosely coupled so I can easily change the DataSource at a later date.

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  • Asp net aspx page and webcontrol issue

    - by Josemalive
    Hello, I have a class that inherits from Page, called APage. public abstract class APage: Page { protected Repeater ExampleRepeater; .... protected override void OnLoad(EventArgs e) { if (null != ExampleRepeater) { ExampleRepeater.DataSource = GetData(); ExampleRepeater.DataBind(); } base.OnLoad(e); } } For other hand i have an aspx page called Default that inherits from this APage: public partial class Default : APage { } on the design part of this Default page, i have a repeater: <asp:Repeater ID="ExampleRepeater" runat="server"> <ItemTemplate> <%# DataBinder.Eval(Container.DataItem, "Name") %><br/> </ItemTemplate> </asp:Repeater> This repeater is datasourced at the base APage load event, but at this level this web control is null. Do you have any idea why the control is null in the base page? Thanks in advance. Best Regards. Jose.

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  • Reflection: cast an object to subclass without use instaceof

    - by Fabrizio
    I have this simple interface/class: public abstract class Message { } public class Message1 extends Message{ } public class Message2 extends Message{ } And an utility class: public class Utility { public void handler(Message m){ System.out.println("Interface: Message"); } public void handler(Message1 m){ System.out.println("Class: Message1"); } public void handler(Message2 m){ System.out.println("Class: Message2"); } } Now, the main class: public static void main(String[] args) { Utility p=new Utility(); Message1 m1=new Message1(); p.handler(m1); Message m=(Message) m1; p.handler(m); } The output is Class: Message1 Interface: Message I would that p.handler(m) call the method p.handler(m:Message1) I don't want use the "manual" command instanceof because I have many cases: if(m instance of Message1) p.handler((Message1)m) else if (m instanceof Message2) p.handler((Message2)m) ... If I call m.getClass() I obtain "mypackage.Message1", so the subclass and not the superclass. I try with this code (use reflection): p.handler(m.getClass().cast(m)); But the output is Interface: Message So, this is my problem. I would do a runtime cast of superclass object to subclassobject without use the "code command" istanceof. I would a right command like this: p.handler((m.getclass)m); How can I obtain it? It's possible? Thank in advance. Fabrizio

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  • Storing class constants (for use as bitmask) in a database?

    - by fireeyedboy
    Let's say I have a class called Medium which can represent different types of media. For instance: uploaded video embedded video uploaded image embedded image I represent these types with contants, like this: class MediumAbstract { const UPLOAD = 0x0001; const EMBED = 0x0010; const VIDEO = 0x0100; const IMAGE = 0x1000; const VIDEO_UPLOAD = 0x0101; // for convenience const VIDEO_EMBED = 0x0110; // for convenience const IMAGE_UPLOAD = 0x1001; // for convenience const IMAGE_EMBED = 0x1010; // for convenience const ALL = 0x1111; // for convenience } Thus, it is easy for me to do a combined search on them on an (abstract) repository, with something like: { public function findAllByType( $type ) { ... } } $media = $repo->findAllByType( MediumAbstract::VIDEO | MediumAbstract::IMAGE_UPLOAD ); // or $media = $repo->findAllByType( MediumAbstract::ALL ); // etc.. How do you feel about using these constant values in a concrete repository like a database? Is it ok? Or should I substitute them with meaningful data in the database. Table medium: | id | type | location | etc.. ------------------------------------------------- | 1 | use constants here? | /some/path | etc.. (Of course I'll only be using the meaningful constants: VIDEO_UPLOAD, VIDEO_EMBED, IMAGE_UPLOAD and IMAGE_EMBED)

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  • Is there a way to pass another parameter in the preg_replace_callback callback function?

    - by DaNieL
    mmmh guys, i really hope my english is good enaught to explain what i need. Lets take this example (that is just an example!) of code: class Something(){ public function Lower($string){ return strtolower($string); } } class Foo{ public $something; public $reg; public $string; public function __construct($reg, $string, $something){ $this->something = $something; $this->reg = $reg; $this->string = $string; } public function Replace(){ return preg_replace_callback($this->reg, 'Foo::Bar', $this->string); } public static function Bar($matches){ /* * [...] * do something with $matches and create the $output variable * [...] */ /* * I know is really useless in this example, but i need to have an istance to an object here * (in this example, the Something object, but can be something else!) */ return $this->something->Lower($output); } } $s = new Something(); $foo = new Foo($myregexp, $mystring, $s); $content = $foo->Replace(); So, the php manual say that to use a class method as callback in preg_replace_callback(), the method must be abstract. I need to pass an instance of a previuosly initialized object (in the example, an instance of the Something class) at the callback function. I tryed to use call_user_func(), but doesnt work (becose in this way i miss the matches parameter). Is there a way to do that, or have i to separate the process (doing before preg_match_all, for each match retrieve the replace value, and then a simple preg_replace)?

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  • C# Inheritence: Choosing what repository based on type of inherited class

    - by Oskar Kjellin
    I have been making a program that downloads information about movies from the internet. I have a base class Title, which represents all titles. Movie, Serie and Episode are inherited from that class. To save them to the database I have 2 services, MovieService and SerieService. They in turn call repositories, but that is not important here. I have a method Save(Title title) which I am not very happy with. I check for what type the title is and then call the correct service. I would like to perhaps write like this: ITitleService service = title.GetService(); title.GetSavedBy(service); So I have an abstract method on Title that returns an ITitleSaver, which will return the correct service for the instance. My question is how should I implement ITitleSaver? If I make it accept Title I will have to cast it to the correct type before calling the correct overload. Which will lead to having to deal with casting once again. What is the best approach to dealing with this? I would like to have the saving logic in the corresponding class.

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  • Setting database-agnostic default column timestamp using Hibernate

    - by unsquared
    I'm working on a java project full of Hibernate (3.3.1) mapping files that have the following sort of declaration for most domain objects. <property name="dateCreated" generated="insert"> <column name="date_created" default="getdate()" /> </property> The problem here is that getdate() is an MSSQL specific function, and when I'm using something like H2 to test subsections of the project, H2 screams that getdate() isn't a recognized function. It's own timestamping function is current_timestamp(). I'd like to be able to keep working with H2 for testing, and wanted to know whether there was a way of telling Hibernate "use this database's own mechanism for retrieving the current timestamp". With H2, I've come up with the following solution. CREATE ALIAS getdate AS $$ java.util.Date now() { return new java.util.Date(); } $$; CALL getdate(); It works, but is obviously H2 specific. I've tried extending H2Dialect and registering the function getdate(), but that doesn't seem to be invoked when Hibernate is creating tables. Is it possible to abstract the idea of a default timestamp away from the specific database engine?

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  • Accessing Static Methods on a Generic class in c#

    - by mrlane
    Hello, I have the following situation in code, which I suspect may be a bit dodgey: I have a class: abstract class DataAccessBase<T> : IDataAccess where T : AnotherAbstractClass This class DataAccessBase also has a static factory method which creates instances of derived classes of itself using an enum value in a which statement to decide which derived type to create: static IDataAccess CreateInstance(TypeToCreateEnum) Now, the types derived from DataAccessBase<T> are themselves NOT generic, they specify a type for T: class PoLcZoneData : DataAccessBase<PoLcZone> // PoLcZone is derived from AnotherAbstractClass So far I am not sure if this is pushing the limits of good use of generics, but what I am really concerned about is how to access the static CreateInstance() method in the first place: The way I am doing this at the moment is to simply pass any type T where T : AnotherAbstractClass. In particular I am passing AnotherAbstractClass itself. This allows compilation just fine, but it does seem to me that passing any type to a generic class just to get at the statics is a bit dodgey. I have actually simplified the situation somewhat as DataAccessBase<T> is the lower level in the inheritance chain, but the static factory methods exists in a middle tier with classes such as PoLcZoneData being the most derived on the only level that is not generic. What are peoples thoughts on this arrangement?

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  • When virtual inheritance IS a good design?

    - by 7vies
    EDIT3: Please be sure to clearly understand what I am asking before answering (there are EDIT2 and lots of comments around). There are (or were) many answers which clearly show misunderstanding of the question (I know that's also my fault, sorry for that) Hi, I've looked over the questions on virtual inheritance (class B: public virtual A {...}) in C++, but did not find an answer to my question. I know that there are some issues with virtual inheritance, but what I'd like to know is in which cases virtual inheritance would be considered a good design. I saw people mentioning interfaces like IUnknown or ISerializable, and also that iostream design is based on virtual inheritance. Would those be good examples of a good use of virtual inheritance, is that just because there is no better alternative, or because virtual inheritance is the proper design in this case? Thanks. EDIT: To clarify, I'm asking about real-life examples, please don't give abstract ones. I know what virtual inheritance is and which inheritance pattern requires it, what I want to know is when it is the good way to do things and not just a consequence of complex inheritance. EDIT2: In other words, I want to know when the diamond hierarchy (which is the reason for virtual inheritance) is a good design

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  • Design considerations for temporarily transforming a player into an animal in a role playing game

    - by mikedev
    I am working on a role playing game for fun and to practice design patterns. I would like players to be able to transform themselves into different animals. For example, a Druid might be able to shape shift into a cheetah. Right now I'm planning on using the decorator pattern to do this but my question is - how do I make it so that when a druid is in the cheetah form, they can only access skills for the cheetah? In other words, they should not be able to access their normal Druid skills. Using the decorator pattern it appears that even in the cheetah form my druid will be able to access their normal druid skills. class Druid : Character { // many cool druid skills and spells void LightHeal(Character target) { } } abstract class CharacterDecorator : Character { Character DecoratedCharacter; } class CheetahForm : CharacterDecorator { Character DecoratedCharacter; public CheetahForm(Character decoratedCharacter) { DecoratedCharacter= decoratedCharacter; } // many cool cheetah related skills void CheetahRun() { // let player move very fast } } now using the classes Druid myDruid = new Druid(); myDruid.LightHeal(myDruid); // casting light heal here is fine myDruid = new CheetahForm(myDruid); myDruid.LightHeal(myDruid); // casting here should not be allowed Hmmmm...now that I think about it, will myDruid be unable to us the Druid class spells/skills unless the class is down-casted? But even if that's the case, is there a better way to ensure that myDruid at this point is locked out from all Druid related spells/skills until it is cast back to a Druid (since currently it's in CheetahForm)

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  • Hibernate triggering constraint violations using orphanRemoval

    - by ptomli
    I'm having trouble with a JPA/Hibernate (3.5.3) setup, where I have an entity, an "Account" class, which has a list of child entities, "Contact" instances. I'm trying to be able to add/remove instances of Contact into a List<Contact> property of Account. Adding a new instance into the set and calling saveOrUpdate(account) persists everything lovely. If I then choose to remove the contact from the list and again call saveOrUpdate, the SQL Hibernate seems to produce involves setting the account_id column to null, which violates a database constraint. What am I doing wrong? The code below is clearly a simplified abstract but I think it covers the problem as I'm seeing the same results in different code, which really is about this simple. SQL: CREATE TABLE account ( INT account_id ); CREATE TABLE contact ( INT contact_id, INT account_id REFERENCES account (account_id) ); Java: @Entity class Account { @Id @Column public Long id; @OneToMany(cascade = CascadeType.ALL, orphanRemoval = true) @JoinColumn(name = "account_id") public List<Contact> contacts; } @Entity class Contact { @Id @Column public Long id; @ManyToOne(optional = false) @JoinColumn(name = "account_id", nullable = false) public Account account; } Account account = new Account(); Contact contact = new Contact(); account.contacts.add(contact); saveOrUpdate(account); // some time later, like another servlet request.... account.contacts.remove(contact); saveOrUpdate(account); Result: UPDATE contact SET account_id = null WHERE contact_id = ? Edit #1: It might be that this is actually a bug http://opensource.atlassian.com/projects/hibernate/browse/HHH-5091

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  • using indexer to retrieve Linq to SQL object from datastore

    - by fearofawhackplanet
    class UserDatastore : IUserDatastore { ... public IUser this[Guid userId] { get { User user = (from u in _dataContext.Users where u.Id == userId select u).FirstOrDefault(); return user; } } ... } One of the developers in our team is arguing that an indexer in the above situation is not appropriate and that a GetUser(Guid id) method should be prefered. The arguments being that: 1) We aren't indexing into an in-memory collection, the indexer is basically performing a hidden SQL query 2) Using a Guid in an indexer is bad (FxCop flagged this also) 3) Returning null from an indexer isn't normal behaviour 4) An API user generally wouldn't expect any of this behaviour I agree to an extent with (most of) these points. But I'm also inclined to argue that one of the characteristics of Linq is to abstract the database access to make it appear that you're simply working with a bunch of collections, even though the lazy evaluation paradigm means those collections aren't evaluated until you run a query over them. It doesn't seem inconsistent to me to access the datastore in the same manner as if it was a concrete in-memory collection here. Also bearing in mind this is an inherited codebase which uses this pattern extensively and consistently, is it worth the refactoring? I accept that it might have been better to use a Get method from the start, but I'm not yet convinced that it's completely incorrect to be using an indexer. I'd be interested to hear all opinions, thanks.

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