Inject of remote EJB interface into external module

Question

I have an EAR application with three modules:

beans are in "app-ejb" module
remote interfaces are in "app-remote"
web services are in "app-war"
app-ejb and app-war use app-remote as library.

all are packaged in "app.ear".

This is working fine, but now I have to use the same beans outside the EAR application, and injection is not working.

I have in app-ejb:

@Stateless
@LocalBean
public class Services implements ServicesRemote {
  [...]
}

and his remote interface in app-remote:

@Remote
public interface ServicesRemote {
  [...]
}

In my app-war I can inject the remote bean without problem:

@Stateless
@LocalBean
public class UseServices {
  @EJB
  private ServicesRemote services;
  [...]
}

Anyway in my external ejb application, deployed as stand-alone and using the same ejb-remote as library, if I try to inject the same EJB like this:

@Stateless
@LocalBean
public class UseServicesFromAnotherApp {
  @EJB
  private ServicesRemote services;
  [...]
}

Glassfish (4.1) give me an error "Class [ Lcom/[...]/ServicesRemote; ] not found".

Is this expected? How can I inject the remote bean correctly?

there's no "whole error log", the only line I get is: [2016-10-31T14:38:47.657-0300] [glassfish 4.1] [SEVERE] [] [global] [tid: _ThreadID=43 _ThreadName=admin-listener(3)] [timeMillis: 1477935527657] [levelValue: 1000] [[ Class [ Lcom/..../ServicesRemote; ] not found. Error while loading [ class com....UseServicesFromAnotherApp ]]] — moretti.fabio

garfield garfield · Accepted Answer · 2016-11-01T05:30:06

Injection doesn't work with remote interfaces. Beans that are "injectable", live inside container's JVM and are available for injection to other beans inside the same application. The same holds true for accessing beans in another application in the same container, although applications may live in the same JVM. Since remote methods are originated from another JVM or another application, injection is not possible. You must use JNDI lookup instead to get a reference to a remote bean.

As a matter or personal taste, I would stay away from EJB Remote interfaces, and instead I would use another "remoting" technique such as REST.

Inject of remote EJB interface into external module

2 Answers