Accessing an EJB in Another Application

Normally, you cannot have EJBs communicating across EAR files, that is, across applications that are deployed in separate EAR files. The only way for an EJB to access an EJB that was deployed in a separate EAR file is to declare it to be the parent of the client. Only children can invoke methods in a parent.

For example, there are two EJBs, each deployed within their EAR file, called sales and inventory, where the sales EJB needs to invoke the inventory EJB to check to see if enough widgets are available. Unless the sales EJB defines the inventory EJB to be its parent, the sales EJB cannot invoke any mehtods in the inventory EJB, because they are both deployed in separate EAR files. So, define the inventory EJB to be the parent of the sales EJB and the sales EJB can now invoke any method in its parent.

You can only define the parent during deployment with the deployment wizard. See the "Deploying Applications" section in the "Configuration and Deployment" chapter in Oracle Application Server Containers for J2EE User's Guide on how to define the parent application of a bean. For broader issues on how to package your classes for method invocation, see "Directory Structure Recommendations for EJB Development".