Re: EJB bites back

From:

Lew <lew@lewscanon.com>

Newsgroups:

comp.lang.java.programmer

Date:

Sat, 08 Dec 2007 01:46:25 -0500

Message-ID:

<w66dnYp_Z5FcoMfanZ2dnUVZ_qGknZ2d@comcast.com>

Lew wrote:

sasuke wrote:

For the past few days I have been trying to understand the complicated
concept behind EJB 3 but to no avail. I even haven't been able to run
a sample 'Hello world' app using the Netbeans IDE. Here are a few
questions I have in mind:

2 Do I have to package the entire j2ee.jar file and give it to the
client(desktop application) if they want to avail the services of the
EJB components deployed on my server. I ask this because when
programming the client we use the @EJB annotation to dynamically
locate and inject the EJB inside the EJB reference.

Quoting from <http://java.sun.com/javaee/5/docs/tutorial/doc/bnbls.html>

Enterprise beans run in the EJB container, a runtime environment
within the Application Server (see Container Types).

You need an app server like JBoss or GlassFish.

Oh, you're trying to annotate the client side.

<http://java.sun.com/javaee/5/docs/tutorial/doc/bnbmg.html#bnbmh>

To create an enterprise bean that allows remote access, you must do one of the following:

    * Decorate the business interface of the enterprise bean with the @Remote annotation:

      @Remote
      public interface InterfaceName { ... }

    * Decorate the bean class with @Remote, specifying the business interface or interfaces:

      @Remote(InterfaceName.class)
      public class BeanName implements InterfaceName { ... }

Now I'm reading
<http://java.sun.com/javaee/5/docs/tutorial/doc/bnbnj.html>
for the client side.

the application client container injects the resource references at runtime.

It seems that besides JBoss and GlassFish (and WebLogic and WebSphere and
....), there is a little program from Sun called 'appclient' that will run the
client app.
<http://docs.sun.com/app/docs/doc/819-3675/appclient-1m?a=view>

I never knew that. I always thought you needed an app server to run EJB
clients. Turns out, not all containers are app servers.

--
Lew