What is the content of J2EE EAR, WAR, and JAR files?
J2EE defines that all the EJB classes should be packaged in a JAR file. All the web components (JSPs, static pages, Servlets, gifs) should be packaged in a WAR file. All the classes for the Application Client should be packaged in a JAR file. EAR file will contain all the JARs and WARs belonging to the Application. It is important to note that each JAR, WAR, and EAR will contain a Deployment Descriptor. The Deployment Descriptor is an XML based file.