This talk describes the tag extension framework introduced by the JSP 1.1 specification to allow custom action elements to be developed in a portable way. Custom actions, implemented as JavaBeans-like classes, can be used to process HTTP request data as well as generating the dynamic parts of the response.

The audience is expected to be familiar with JSP in general, so only a very brief overview of the JSP technology as such is provided. All framework classes and interfaces, as well as the Tag Library Descriptor (TLD) and the taglib directive, are described using a simple example. More complete, practical examples are then used to to demonstrate various techniques, such as processing the custom action element's body, introducing scripting variables and cooperation between multiple custom actions.

The focus of the presentation is on the JSP 1.1 features, but since the JSP 1.2 specification should be close to finalized by the time for this event, I will also present the new features introduced in the 1.2 version. Depending on the status of the "standard tag library" specification, I may also include information about what can be expected on this front.