Lookup and invoke a _local_ EJB via a remote EJB by a remote client

[virtuellesnugat]

Hi there,

I'm new to the jboss AS and the EJB. The book I've read doesn't help me, since the new JNDI naming changes so much.

But during the last days I've managed to setup the server, deploy some remote stateful and stateless session beans. But now I'm trying something different:

• Local stateless session bean named "TimeBean", with it's interface "ITimeLocal"
• Remote stateless session bean named "CallerBean", with it's interface "ICallerRemote"
• and a remote Client named "CallerClientBean"

ITimeLocal

package test.jboss.umweg.server.local;

import javax.ejb.Local;

@Local
public interface ITimeLocal {
    public long getTime();
}

TimeBean

package test.jboss.umweg.server.local;

import java.util.Date;

import javax.ejb.Local;
import javax.ejb.Stateless;

@Stateless
@Local(ITimeLocal.class)
public class TimeBean implements ITimeLocal {

    @Override
    public long getTime() {
        return new Date().getTime();
    }

}

So that's just the local bean. It was deployed successfully and the JNDI Bindings where created.

The call from the CallerClientBean to the CallerBean works fine (I tested with "return 0").

But when I tried the real call it wouldn't work:

Extracted from CallerBean

@Override
    public long askTime() {
        // lookup and invoke Local Bean, return time
        try {
            Context context = getInitialContext();
            ITimeLocal szb = (ITimeLocal) context.lookup(getJndiName());
            long time = szb.getTime();
            System.out.println("Time: " + time);
            return time;
        } catch (NamingException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return 0;
    }

I build the InitialContext like this (though I didn't set a "jboss-ejb-client.properties" on server side, maybe that's a problem):

private InitialContext getInitialContext() throws NamingException {
       Hashtable p = new Hashtable();
        p.put(Context.URL_PKG_PREFIXES, "org.jboss.ejb.client.naming");
        return new InitialContext(p);
    }

And I tried two different JNDI names:

• the same I've been building the other ones:
  ejb:/TimeBean//TimeBean!test.jboss.umweg.server.local.ITimeLocal
• and the global JNDI binding I got from the deploy:
  java:global/TimeBean/TimeBean!test.jboss.umweg.server.local.ITimeLocal

But I guess my main-problem is, that I'm not aware of howto call a local bean. And I couldn't find anything really helpful. I didn't post the Exceptions (first runtime, the illegalState), but I bet my faults are obvious to most people here

Thanks!!

[virtuellesnugat]

According to the Java EE Tutorial 6 (published 04/2012) there are three ways to create a local session bean:

-------------------------------

■ Create an enterprise bean implementation class that does not implement a business

interface, indicating that the bean exposes a no-interface view to clients. For example:

@Session

public class MyBean { ... }

■ Annotate the business interface of the enterprise bean as a @Local interface. For example:

@Local

public interface InterfaceName { ... }

■ Specify the interface by decorating the bean class with @Local and specify the interface

name. For example:

@Local(InterfaceName.class)

public class BeanName implements InterfaceName { ... }

-------------------------------

If I try to add the "@Session" annotation to my class, eclipse doesn't recognize it and recommends to create such an annotation. (Wrong Setup? Just added the as7/bin/client/jboss-client.jar as a lib)

So, there are only two ways left.

-------------------------------

■ To obtain a reference to the no-interface view of an enterprise bean through dependency

injection, use the javax.ejb.EJB annotation and specify the enterprise bean’s

implementation class:

@EJB

ExampleBean exampleBean;

■ To obtain a reference to the no-interface view of an enterprise bean through JNDI lookup,

use the javax.naming.InitialContext interface’s lookupmethod:

ExampleBean exampleBean = (ExampleBean)

InitialContext.lookup("java:module/ExampleBean");

-------------------------------

Dependency Injection fails because I cannot deploy these .jar files.

Well and the JNDI lookup won't work either, regardless if I use "java:module/ExampleBean" or the longer option stated out by the server.

Could PLEASE anyone help me? It has to be possible to call a local stateless session bean...

[wdfink]

To call another Bean inside the container vie @Local you should not use InitialContext.

Injection will do the work.

{code}

@Stateless

public class My1Bean implements My1Remote {

    @EJB

    MyIntern intern;

  public void myMethod() {

    intern.hello();

  }

}

@Local

public interface MyIntern {

    public void hello();

}

@Stateless

public class MyInternBean implements MyIntern {

    @Override

    public void hello() {

        // DO something

    }

}

{code}

You might have a look to the JBoss quickstarts

[virtuellesnugat]

Thank you that did it.

Now I know why it wouldn't deploy:

I seperated both server-sided beans into single jars. Consequently the jar containing the remote bean would fail, because of the implicit injection to the local bean, which wasn't reachable.

But now both ways works:

- Setting up an .ear file containing both beans

- Exporting one .jar file containing both beans

Thanks a lot!

Furthermore I think I may have mixed up some different approaches to expose the beans.