[vanstonecypher]

I’m experimenting with building an EJB/JSP app using MyEclipse and JBoss 3.2.5. I’m quite comfortable with building web apps, so this is really an excuse to play with EJBs and learn something new. 😀

Anyway, I created three projects: a web module, ejb module and enterprise application.

The application module just contains the other two and I use MyEclipse to deploy it to JBoss.

The ejb module has a single session bean with the following XDoclet comment:

 * @ejb.bean name = "HelloBean"
 *           type = "Stateless"
 *           display-name = "HelloBean"
 *           description = "HelloBean EJB"
 *           view-type = "remote"
 *           jndi-name = "ejb/HelloBean"

It is configured with the “Standard EJB” XDoclet with the following options: deploymentdescriptor, fileset, homeinterface, jboss, packageSubstitution, remoteinterface and session. I can build the EJB just fine and all seems to work well my jboss.xml contains:

      <session>
         <ejb-name>HelloBean</ejb-name>
         <jndi-name>ejb/HelloBean</jndi-name>

      </session>

In the web module I built a jsp with the following init function:

<%!
  private HelloBean hello = null;
  public void jspInit() {
    try {
      final InitialContext ic = new InitialContext();
      Object objRef = ic.lookup("HelloBean");
      HelloBeanHome home = (HelloBeanHome)PortableRemoteObject.narrow(objRef, HelloBeanHome.class);
      hello = home.create();
    } 
    catch (Exception ex) {
      // should do something usefull....
    }
  }
%>

All of this works fine and I can access the bean in the JSP, but here is where I’m confused. In the previous definition, the jni-name parameter is “ejb/HelloBean” while I had to use “HelloBean” in the lookup method. Why is that? Shouldn’t it be “ejb/HelloBean”? (That doesn’t work by the way, I’ve tried it.)

When I look at JBoss’ JMX Management Console I see:

 jboss.j2ee

    * jndiName=HelloBean,plugin=pool,service=EJB
    * jndiName=HelloBean,service=EJB

I’m sure I’m missing something simple, but I don’t know what. Anyone have a suggestion?

[Riyad Kalla]

Since this is a general EJB question I’m going to move it to Random Thoughts, but will also ask our EJB guy if he has any ideas that might help you.

[Greg]

I had to lookup a tutorial to get some clues about this. Here is a link to a helpful doc.

http://www.informit.com/articles/article.asp?p=28281&seqNum=3

Here are a couple of interesting sections.

...
The J2EE specification recommends that all references to enterprise beans be organized in the java:comp/env/ejb context of the application component's environment.
...
An ejb-ref-name element that specifies the name of the reference relative to the java:comp/env context. To place the reference under the recommended java:comp/env/ejb context, use an ejb/link-name form for the ejb-ref-name value.
...

An EJB reference is scoped to the application component whose declaration contains the ejb-ref element.

So basically, in the generated xml files ejb/HelloBean is short for java:comp/env/ejb/HelloBean. And accessing just HelloBean works because there isn’t another HelloBean defined elsewhere.

[vanstonecypher]

Thanks for the link, it has plenty of information to digest. However I don’t think it answers my basic question. What I was doing was looking through Sun’s J2EE Tutorial and using their code examples to build the HelloBean. However, when I used “ejb/HelloBean” I got the following exception:

javax.naming.NameNotFoundException: ejb not bound

After digging around in the deployed directories and generated xml files, I found that ebj-jar.xml had the following entry:

         <ejb-name>HelloBean</ejb-name>

When I changed it to:

         <ejb-name>ejb/HelloBean</ejb-name>

The reference in the JSP worked (although “java:comp/env/ejb/HelloBean” does not.) My question now is what “name” am I referencing in the JSP? I thought it was the JNDI name (ejb/HelloBean) but it doesn’t seem to be. I don’t really want to edit the generated files since it seems to defeat the purpose (which I why I wanted to use MyEclipse in the first place!) Am I specifying the XDoclet parameters incorrectly, deploying the app incorrectly, or just not understanding how everything is supposed to be referenced? 😯

[vanstonecypher]

I thought I’d post the solution in case someone else is having this problem. As I thought, it turns out to be something simple. I didn’t have the destDir set for the jboss XDoclet to src/META-INF, so the jboss.xml file was not in the right place. By default jboss simply uses the bean name, which explains my confusion. 😳

[Riyad Kalla]

Thanks for posting the solution, this is very helpful to keep this forums a valueable resource for the users.

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