Access EJB from Java Application

[shashi wagh]

Hi.........

I have a EJB 3 application which is deployed on JBoss server.

I have develop a java application which access the EJB. It works fine when both application on same machine.

My problem is I want to place EJB @ centralized location and client @ remote places.

If any changes happen to EJB it should not required to rebuild the jar @ every places.

I am calling EJB like this

  
Properties properties = new Properties();
properties.put( "java.naming.factory.initial", "org.jnp.interfaces.NamingContextFactory" );
properties.put( "java.naming.factory.url.pkgs", "=org.jboss.naming:org.jnp.interfaces" );
properties.put( "java.naming.provider.url", "serverIp:1099" );
 
try
{
	InitialContext ctx = new InitialContext( properties );
	MyBeanRemote bean = (MyBeanRemote)ctx.lookup( "MyBean/remote" );
	System.out.println( bean.doSomething() );
	System.out.println( "Press Enter to Exit" );
	System.in.read();
}
catch ( NamingException e )
{
	e.printStackTrace();
}

  

When I put it on different machine It will not get MyBeanRemote class cause it is not @ every client machine

Please suggest something

I want to extend this application to SWING and calling EJB from Swing app. so that GUI is @ client side and Business Logic is @ server.


Thanks

[Chinna Eranna]

>>My problem is I want to place EJB @ centralized location and client @ remote places.

This is one of the problem that EJB tries to solve.

MyBeanRemote should be an interface.. and it must be available at the client in the remote machines.

[shashi wagh]

Following are the Steps which I have performed

1 Created EJB 3 application in Myeclipse
2 Deployed it on JBoss 4.2
3 Created a Java Application in MyEclipse
4 Configure the build path to access the EJB application
5 Start the Server
6 Run the Application in MyEclipse.
7 It Works Fine.


Now I export the Client application to Jar --------> TestClient.jar
Now I export the Interfaces in EJB application to --------> TestBeanInterface.jar

Following is the command I used to run the Client
java -cp "TestBeanInterface.jar;jbossall-client.jar";TestClient.jar com.gts.ejbdemo.client.MyBeanClient

N got the following output

    

D:\ejbclientjar>java -cp "TestBeanInterface.jar;jbossall-client.jar";TestClient.jar com.gts.ejbdemo.client.MyBeanClient
javax.naming.CommunicationException [Root exception is java.lang.ClassNotFoundException: com.gts.ejbdemo.sessionbeans.MyBeanRemote (
no security manager: RMI class loader disabled)]
        at org.jnp.interfaces.NamingContext.lookup(NamingContext.java:786)
        at org.jnp.interfaces.NamingContext.lookup(NamingContext.java:627)
        at javax.naming.InitialContext.lookup(Unknown Source)
        at com.gts.ejbdemo.client.MyBeanClient.main(MyBeanClient.java:26)
Caused by: java.lang.ClassNotFoundException: com.gts.ejbdemo.sessionbeans.MyBeanRemote (no security manager: RMI class loader disabl
ed)
        at sun.rmi.server.LoaderHandler.loadProxyClass(Unknown Source)
        at java.rmi.server.RMIClassLoader$2.loadProxyClass(Unknown Source)
        at java.rmi.server.RMIClassLoader.loadProxyClass(Unknown Source)
        at sun.rmi.server.MarshalInputStream.resolveProxyClass(Unknown Source)
        at java.io.ObjectInputStream.readProxyDesc(Unknown Source)
        at java.io.ObjectInputStream.readClassDesc(Unknown Source)
        at java.io.ObjectInputStream.readOrdinaryObject(Unknown Source)
        at java.io.ObjectInputStream.readObject0(Unknown Source)
        at java.io.ObjectInputStream.readObject(Unknown Source)
        at java.rmi.MarshalledObject.get(Unknown Source)
        at org.jnp.interfaces.MarshalledValuePair.get(MarshalledValuePair.java:72)
        at org.jnp.interfaces.NamingContext.lookup(NamingContext.java:710)
        ... 3 more
 
D:\ejbclientjar>

Tell me what is I am doing wrong.........

But when I export all ejb application to jar It works................

Edited by: shashiwagh on Feb 26, 2010 4:53 AM

[Kai Wähner]

Now I export the Client application to Jar --------> TestClient.jar
Now I export the Interfaces in EJB application to --------> TestBeanInterface.jar

Following is the command I used to run the Client
java -cp "TestBeanInterface.jar;jbossall-client.jar";TestClient.jar com.gts.ejbdemo.client.MyBeanClient

Simply using a java client and including the ejb jar is not enough...

There are two possibilities to call EJBs from a remote client, which is not deployed at the application server:
1) Use an application client (JEE implementations offer an ejb container, web container and application client container - the latter one is for using jee features such as dependency injection from a J2SE client)
2) Get the ejb via JNDI lookup. you have to configure the server url, port and so on.