who calls the constructor witth parameter (Castle.Windsor) - castle-windsor

I am learning castle.windsor following the tutorial online. this is the simple sample code:
public class Form1 {
private readonly HttpServiceWatcher serviceWatcher;
private System.ComponentModel.Container components = null;
public Form1()
{
InitializeComponent();
}
public Form1(HttpServiceWatcher serviceWatcher) : this()
{
this.serviceWatcher = serviceWatcher;
}
}
HttpServiceWatcher is in the xml conf file.
My question is: who is calling the constructor that has the parameter: public Form1(Http....) ?
at the program.cs i have this:
container.AddComponent("form.component",typeof(Form1));
Form1 form1 = (Form1) container["form.component"];
Application.Run(form1);

The container calls the constructor when it creates the requested object. The constructor that gets called is the constructor with the most arguments that the container can satisfy.

The dependency container itself creates the object (and thus calls the constructor).

Related

Signal is never being injected - robotlegs2.0

In app config file I have a Signal/Command mapping
signalCommandMap.map(DisconnectUserSignal).toCommand(DisconnectUserCommand);
Then,
I have two connection classes:
public class BaseConnection implements IBaseConnection
{
// When I am trying to inject the signal here:
[Inject] public var disconnectUserSignal:DisconnectUserSignal; // it is always null
_netConnection = new NetConnection();
...
}
and
public class BBConnection extends DefaultConnectionCallback implements IBBConnection
{
// When I am trying to inject the signal here:
[Inject] public var disconnectUserSignal:DisconnectUserSignal; // it works perfectly fine
_baseConnection = new BaseConnection(this);
}
Is there any suggestion of what might be the reason?
Thank you
After going through the robotlegs framework documentation - I found the answer:
I changed the _baseConnection to be an interface, and moved everything from BaseConnection's constructor into init method and now I am injecting it inside my BBConnection.
Here how BBConnection looks now:
[Inject]
public var baseConnection:IBaseConnection;
public function BBConnection()
{
}
[PostConstruct]
public function init():void
{
baseConnection.init(this);
}
Now I can successfully inject Disconnect signal inside base connection.
Source: https://github.com/robotlegs/robotlegs-framework/wiki/common-problems#injected-properties-are-null-in-constructor

Windsor, inject container in class

Hi have the following component registered into Castle Windsor:
public class CommandDispatcher : IServiceCommandDispatcher
{
private readonly IWindsorContainer container;
public CommandDispatcher(IWindsorContainer container)
{
this.container = container;
}
#region IServiceCommandDispatcher Members
public void Dispatch<TCommand>(TCommand command) where TCommand : IServiceCommand
{
var handler = container.Resolve<IServiceCommandHandler<TCommand>>();
handler.Handle(command);
}
#endregion
}
And the dispatcher is registered in the following way:
Component
.For<IServiceCommandDispatcher>()
.ImplementedBy<CommandDispatcher>(),
But the field container is null when I resolve an instance of the dispatcher.
What should I do in order to pass the container to the resolved children items?
Windsor solves this problem for you with the Typed Factory Facility.
In the below example I want the implementation of ICommandHandlerFactory to resolve my command handler from my windsor container.
class CommandDispatcher : IServiceCommandDispatcher
{
private readonly ICommandHandlerFactory factory;
public CommandDispatcher(ICommandHandlerFactory factory)
{
this.factory = factory;
}
public void Dispatch<T>(T command) where T : IServiceCommand
{
var handler = this.factory.Create(command);
handler.Handle(command);
this.factory.Destroy(handler);
}
}
To achieve this I only need to create the ICommandHandlerFactory Interface.
public interface ICommandHandlerFactory
{
Handles<T> Create<T>(T command) where T : IServiceCommand;
void Destroy(object handler);
}
No implementation of ICommandHandlerFactory is required as Windsor will create the implementation. Windsor uses the convention that a method that returns an object is a resolve method and a method that returns void is a release method.
To register the factory you need to include using Castle.Facilities.TypedFactory and then register your factory as follows
container.AddFacility<TypedFactoryFacility>();
container.Register(
Component.For<ICommandHandlerFactory>()
.AsFactory()
);
Just to reiterate you do not have to write any implementation code for your factory.
This works:
container.Register(Component.For<IWindsorContainer>().Instance(container));
It's not ideal, because you still have to call the Resolve method. There may be a better way to do this, using a factory. This looks similar to what you're trying to do:
http://kozmic.net/2010/03/11/advanced-castle-windsor-ndash-generic-typed-factories-auto-release-and-more/

JMockit mock protected method in superclass and still test method in real child class

I am still learning JMockit and need help understanding it.
I am testing a class that uses superclass methods. My test gets a null pointer when it attempts to use the superclass method due to code inside it that uses struts action context to get the session and pull an object from the session.
The method I want to bypass the struts session stuff inside the protected method.
public class MyExtendingClass extends MySuperClass{
public void methodIamTesting(){///}
}
public abstract class MySuperClass{
//I want to mock this method
protected Object myProtectedSuperClassMethod(){
// struts action context code that returns an object//}
}
Test code
#Test
public void testRunsAndDoesntPass() {
Mockit.setUpMock(MySuperClass.class, new MySuperClass(){
public Object myProtectedSuperClassMethod() {
return object;
}
});
// real class method invocation happens
assertEquals(expected, actual);
}
I keep getting NullPointers just like if I didn't have the mock
Not sure what to try next. All the docs and code samples I have read say to just declare the superclass method as public in the setUpMock and it should work.
I can't mock the entire class because that is the class I am testing.
I discovered that I needed to create the MockClass then reference it using setupmock correctly.
I am really falling in love with JMockit.
#MockClass(realClass = MyExtendingClass.class)
public static class MockSuperClass {
final Object object = new Object();
#Mock
public Object myProtectedSuperClassMethod() {
return object;
}}
#Test
public void testRunsAndNowWillPass() {
Mockit.setUpMock(MySuperClass.class, new MockSuperClass(){
public Object myProtectedSuperClassMethod() {
return object;
}});
// real class method invocation happens where i set expected and actual
assertEquals(expected, actual);
}
you mask the parent class implementation out totally #Mocked final MySuperClass base
abstract class MySuperClass{
protected Object myProtectedSuperClassMethod(){
}
class MyExtendingClass extends MySuperClass{
public void methodIamTesting(){///}
}
#Test
public void testRunsAndDoesntPass(#Mocked final MySuperClass base ) {
//you could mask out all the base class implementation like this
new Expectations(){{
invoke(base, "myProtectedSuperClassMethod");
}};
// real class method invocation happens
// ...
assertEquals(expected, actual);
}

Flex Strongly Typed Proxy Classes for Lazy Instantiation

Does anyone know of a framework, preferably some way to have the Flex compiler run an extension or perhaps just a build step that we could generate strongly typed proxy classes of our application's data models.
There are 2 main things we want to do with the proxy's:
At runtime we want to lazily parse and instantiate the instance as accessed (similiar to how Java's Hibernate has Lazy proxy objects)
In an editor application we want to implement setter calls so we can track which objects have been modified
The Proxy is really necessary in this situation beyond things like programatically setting up ChangeWatcther's because we need to track Array adds/remove and possibly track "reference" objects so that when a "reference key" is changed we know to save those objects that are referencing it by key
In the first case we want the proxy to basically abstract when that object is loaded from serialized data, but still pass around references of it with the same public properties and data access pattern if it were the real object.
Basically the proxy would instantiate the object the first time a method is called on it.
I know we could use some AS3 byte-code libraries like as3-commons-bytecode.
Or possibly repurposing the GraniteDS Code Generation.
I'd prefer to generate code because it is a deterministic thing and it'd be nice if we could have a way to debug it at runtime easier.
Does anyone know if I could do something like MXMLC does when it generates AS3 code from MXML files.
Also is there anyway to control "when" in the compilation pipeline I can generate code, because we have a lot of data objects using public fields instead of getter/setters, but that are [Bindable] and so if I could generate the proxy based on the generated getter/setter methods that would work.
Here's an example application data object and proxy classes:
[Bindable]
public class PersonDTO implements Serializable {
private var _name:String;
private var _age:Number
public function get age():Number {
return _age;
}
public function set age(a:Number):void {
_age = a;
}
public function get name():String {
return _name;
}
public function set name(n:String):void {
_name = n;
}
public void readObject(data:*) {
//...
}
}
// GENERATED CLASS BASED ON PersonDTO
public class LazyProxy_PersonDTO extends PersonDTO {
private var _instance:PersonDTO = null;
private var _instanceData:*;
private function getInstance():void {
if (_instance == null) {
_instance = new PersonDTO();
_instance.readObject(_instanceData);
}
}
override public function get age():Number {
//Ensure object is instantiated
return getInstance().age;
}
override public function get name():String {
//Ensure object is instantiated
return getInstance().name;
}
}
// GENERATED CLASS BASED ON PersonDTO
public class LogChangeProxy_PersonDTO extends PersonDTO {
//This will be set in the application
public var instance:PersonDTO;
//set by application
public var dirtyWatcher:DirtyWatcherManager;
override public function set age(a:Number):void {
dirtyWatcher.markAsDirty(instance);
instance.age = a;
}
}
Digging a little deeper into AS3-Commons byte code library it looks like they support generating proxy classes and interceptors.
http://www.as3commons.org/as3-commons-bytecode/proxy.html
public class DirtyUpdateInterceptor implements IInterceptor {
public function DirtyUpdateInterceptor() {
super();
}
public function intercept(invocation:IMethodInvocation):void {
if (invocation.kind === MethodInvocationKind.SETTER) {
if (invocation.arguments[0] != invocation.instance[invocation.targetMember]) {
invocation.instance.isDirty = true;
}
}
}
}

t4mvc : Cannot inherit a controller class which has no default constructor?

I am using T4MVC with MVC2.
I have the following building blocks:
A simple entity interface which defines that every POCO entity must have a long Id property:
public interface IEntity
{
public long Id;
}
A simple POCO class which implements the IEntity interface and has some string properties:
public class CD : IEntity
{
public long Id { get; set; }
public long Name { get; set; }
}
A base controller:
public abstract class EntityController<T> : Controller where T : class, global::IEntity
{
public EntityController(IEntityManager<T> manager);
}
I use this base controller in my CDController (where CDManager implements the IEntityManager interface, which is a UnitOfWork pattern to add CRUD functionality):
public partial class CDController : EntityController<CD>
{
public CDController() : base(new CDManager()) { }
}
When I run my t4 template, this code is generated:
namespace MyApp.Web.Controllers {
public partial class CDController {
[GeneratedCode("T4MVC", "2.0"), DebuggerNonUserCode]
protected CDController(Dummy d) { }
But this gives me an error during compilation:
MyApp.EntityController<CD> does not contain a constructor that takes 0 arguments
How can I solve this?
I wanted by controller base class to be abstract and it's constructor protected and parametrized. Got around this issue by adding a blank constructor to ControllerBase that throws a NotImplementedException.
Doesn't quite feel right but it gets the job done. Only issue is when combined with dependency injection the wrong constructor will be called - since it throws an exception the app will bum out.
Code:
public abstract class ControllerBase : Controller
{
protected object AlwaysSupply { get; private set; }
public ControllerBase()
{
throw new NotImplementedException();
}
public ControllerBase(object alwaysSupply)
{
AlwaysSupply = alwaysSupply;
}
}
This will cause T4MVC to generate compilable code. The fault seems to be it always tries to generate a blank (no parameters) constructor for controller classes.
Hope this helps someone.
I see the problem, and it comes down to T4MVC not quite doing the right thing when dealing with generic classes. Normally it would generate a default ctor for it in a partial class, but the fact that it's generic is throwing it off.
You should be able to work around simply by adding a default ctor yourself, e.g.
public abstract partial class EntityController<T> : Controller where T : class, IEntity {
public EntityController() { }
// etc...
}
I've noticed something very odd:
I've added the empty constructor to the base class, but without the throw new NotImplementedException(); and it works fine.
But here's the odd thing, when calling the controller if I have an url like
/{controller}?params (default action being set to Index in the RouteConfig) the parameterless private controller on the base class is called.
But when I have an url like /{controller}/{action}?params then the constructor with parameters is called.