Hour 10. Using JSP Standard Actions to Organize Your Web Application

What You'll Learn in This Hour:

• How to include Web resources in JSPs or servlets

• How to forward clients to other pages

• How to build reusable elements using the include mechanisms

• How to use applets within your Web applications

All of the programmable elements that you have worked with so far have been in the form of source files that are compiled into classes (for servlets) or in the form of JSP declarations, scriptlets, or expressions. JavaServer Pages add JSP actions to the elements you can use to produce dynamic pages.

JSP actions are represented by tags that, when placed in JavaServer Pages, cause some programmatic behavior to occur. The actions available as part of the core JSP specification are known as standard actions. By convention, they're prefixed with jsp. For example, the <jsp:include> tag that we'll discuss in a moment allows you to include one JSP inside another. In Hour 16, "Extending JSP with New Tags," you'll learn how to create your own custom actions. Then, in Hour 17 you'll be introduced to the Standard Tag Library, a collection of very useful tag extensions.

Many of the examples you have seen so far are difficult to read because they shift frequently between Java and HTML. In fact, one of the biggest complaints about JSP is that the pages end up looking very messy and become very difficult to maintain. In this hour you will see how to organize your JavaServer Pages and servlets to make them much easier to read and maintain.