Page lists
Page lists allow you to avoid hard-coding Uniform Resource Locators (URLs) in servlets and JSP files. A page list specifies the location where a request is to be forwarded, but automatically customizes that location depending on the MIME type of the servlet. Use these properties to specify a markup language and an associated MIME type. For the given MIME type, you also specify a set of pages to invoke.
WebSphere Application Server supplies the PageListServlet servlet, which use to call a JavaServer Pages (JSP) file by name based on the configuration data in the client_types.xml file. This file maps a JSP file to a Uniform Resource Identifier (URI). When the URI is invoked, it specifies another JSP file in a Web module. This support allows you to access multiple URLs without hard-coding them in your servlets.
We can also logically group page lists according to the markup language type, such as, Hypertext Markup Language (HTML) or Wireless Markup Language (WML). This allows applications that use servlets to extend the PageListServlet servlet, to call JSP files which return the proper markup-language type for the client request. For example, a request that originates from a PDA device requires WML data. The application server sends the request to a servlet that extends the PageListServlet servlet, and the servlet calls a JSP file that returns a WML response.
See Also
Client type detection support
client_types.xml
Example: Extending PageListServlet
Web applications: Resources for learning