Packaging An Application

Question

To the expert in J2EE,
I am writing a not so simple application that involves the use of Web and EJBs. In this application has some session beans as follow; SessionBeanA, SessionBeanB, and SessionBeanC, and entity beans as follow; EntityBeanA, EntityBeanB and EntityBeanC.
All of the entity beans are declared as local, but some of the session beans are declared as local and some are declared as remote. The session beans are referenced by servlets in the web component. A session bean may references many entity beans.
My questions are following;
I.     What are the pros/cons to separate Entiy beans and Session beans to two groups of jar files.
1)     Package all entity beans in a module (EntityBeanModule.jar) that contains its own ejb-jar.xml and jboss.xml and all session beans in a module (SessionBeanModule.jar) that contains its own ejb-jar.xml and jboss.xml.
2)     The application directory structure looks the following:
Application.ear
META-INF/
META-INF/application.xml
CoreEntityBeanModule.jar
CoreSessionBeanModule.jar
AppRemoteEntityBeanModule.jar //enity bean remote?
AppLocalEntityBeanModule.jar
AppLocalSessionBeanModule.jar
AppRemoteSessionBeanModule.jar
WebModule.war
lib/
lib/Core.jar //contains all Core java codes
lib/ejb-client.jar //contain remote interfaces for servlets
3)     What are the benefits for doing this? It seems to create a lot more of works in the looking up of the entity beans. Would the invocation of the entity bean be local or remote?
II.     What are the pros/cons to put all Entity beans and Session beans to one jar file.
1)     Package all entity beans and session beans in a jar file (EJBsModule.jar) that contains its own ejb-jar.xml and jboss.xml.
2)     The application directory structure looks the following:
Application.ear
META-INF/
META-INF/application.xml
CoreEJBsModule.jar
AppEJBsModule.jar
WebModule.war
lib/
lib/Core.jar //contains all Core java codes
lib/ejb-client.jar //contain remote interfaces for servlets
3)     What are the benefits for doing this? It saves a lot of works compare to the option I. I can see there is a potential problem for maintenance when the number EJB beans increase to more then 100. What happen when the entity beans need to run on a separate application server?
Thank in advance,
Kam

Answer 1

Hi,
Thank you for all of your reply messages. I used JBoss
for application server and I don't have the GUI editor
to generate the deployment descriptor. If I separate
ejbs into groups based on the functionality. What
happen to the invocation of an ejb when the called
EJBs is in a different jar files that was packaged in
the same ear apllication. Would they automatically
become remote invocation?It will not be remote invocation. If the ejbs are deployed on the same app server it will always be local invocation. This is true as far as WLS is concerned, I am not sure about other app servers. Even if you have not created local interfaces the WLS is smart enough to figure out weather its a local invocation or remote invocation.