Sun Java System Application Server Platform Edition 9 Upgrade and Migration Guide

JSP source files

Java EE specifies how to extend JSP by adding extra custom tags. Product vendors include some custom JSP extensions in their products, simplifying some tasks for developers. However, usage of these proprietary custom tags results in non-portability of JSP files. Additionally, JSP can invoke methods defined in other Java source files as well. The JSPs containing proprietary APIs needs to be rewritten before they can be migrated.