Flex + Java + BlazeDS: Some instances already created on the server are unavailable from Flex

[Jose Velas]

Hi Everyone.
Thank you for all the documentation, and the great forum.

I have a question about the Java Factory; I've read somewhere that: "... the JavaFactory will check if there is already an instance in the scope and return that. If the object is not available then it is instantiated ...", but I don't understand the expression "if the object is not available"?

I am having trouble to find and/or assign classes already instantiated (by another class) in the server, to a declared destination.

Here is the scenario:
I'm developing an application in Java:

J2EE.

I'm running it on a Tomcat 6 server

I'm using BlazeDS to communicate with Flex.

I'm using the RPC's Remoting Service (through RemoteObjects)

There are two java classes that handle Client (Flex) interaction, say ApplicationClass and UserApplicationClass:

ApplicationClass has a reference (attribute) to a UserApplicationClass instance

ApplicationClass should be the one and only entry point (although BlazeDS requires an empty constructor) to instantiate a UserApplicationClass;

UserApplicationClass is instantiated, right after the attribute User has been set on ApplicationClass.

//Java Code

	public class ApplicationClass {
		private User user = null;
		private UserApplicationClass userApplicationClass = null;
		...
		public ApplicationClass {}
		...
		public void setUser(User user) {
			this.user = user;
			this.userApplicationClass = new UserApplicationClass(user);
		}
		...
	}

Up to here everything is fine:
From the Flex client I am able to use ApplicationClass methods, set its User and get the UserApplicationClass attribute from ApplicationClass.

But here is the problem:
When I try to use any method of UserApplicationClass, It doesn't find the class already created on the server, but instead, it instantiates a brand new one (with all of its attributes set to null by using the default constructor).

How could I assure that the destination points to a specified instance on the server, created by another class, and not instantiating a new one?

// Flex Client Code
<mx:Application ... creationComplete="invokeService()"> ... <mx:Script> <![CDATA[ import application.UserApplicationClass; ... private var userApplicationClass :UserApplicationClass; ... private function invokeService():void { applicationClassRemoteObject.getUser(); // Ok userApplicationClass.getUser(); // Ok userApplicationClassRemoteObject.getUser(); // Fails; user null; the JavaFactory //doesn't find the UserApplicationClass instance on the //server and creates a new instance. } ... private function applicationClass_getUser(event:ResultEvent):void { // Validate null ResultEvent ... userApplicationClass = UserApplicationClass(event.result); } ... ]]> </mx:Script> <mx:RemoteObject id="applicationClassRemoteObject" destination="[b][i]ApplicationClass[/i][/b]Destination" showBusyCursor="true"> ... <mx:method name="getUserApplicationClass" result="applicationClass_getUser(event)" /> </mx:RemoteObject> <mx:RemoteObject id="userApplicationClassRemoteObject" destination="[b][i][u]User[/u]ApplicationClass[/i][/b]Destination" showBusyCursor="true"> <mx:method name="getUser" result="userApplicationClass_getUser(event)" /> ... </mx:RemoteObject> ... </mx:Application>

Note: scope attribute (on remoting-config.xml) on both destinations is set to session.

I hope I have been clear; I would really appreciate if you could help me.

Thanks in advance,

AM