If you are currently running ATG 6 on WebLogic or WebSphere and want to migrate to ATG 9.3, you should be aware of some significant differences between the way ATG 6 and ATG 9.3 applications run:
ATG 6 uses special startup scripts and environment variables to modify the WebLogic or WebSphere system CLASSPATH so that an instance of Nucleus runs on WebLogic or WebSphere. The EAR and WAR files you build contain only standard J2EE components and configuration, while Nucleus classes and configuration remain in the ATG installation.
ATG 9 does not modify the WebLogic or WebSphere system CLASSPATH. The applications you build are assembled into EAR files that each run their own instance of Nucleus. These EAR files include all of the class files and (optionally) configuration for the application’s Nucleus components.
When you migrate to ATG 9.3, you must reassemble your applications to take advantage of the new format, which is more modular, easier to maintain, and less likely to result in system resource conflicts. For information about how to reassemble your applications, see Reassembling Your Applications.
