Wednesday, March 16, 2011

JSR-168 Specification / Portal Architecture

The Portlet Specification addresses the following topics

  1. The portlet container contract 
  2. Portlet life cycle management
  3. The definition of window states
  4.  Portlet modes
  5.  Portlet preferences management
  6.  User information
  7.  Packaging and deployment
  8.  Security 
  9.  JSP tags to aid portlet development

Container Contract
The life cycle methods called directly by the container are:

  • init() 
  • destroy() 
  • processAction() 
  • render() 

In addition to the methods above, which are called directly by the container, a GenericPortlet class is provided
that implements the render() method and delegates the call to more specific methods to display the portlet based
on its mode. Developers can extend GenericPortlet and implement as many of these specialized render methods as
are necessary for their portlet. These methods are: Called by render()

Portlet Preferences
as a persistent set of name-value pairs and are referred to as portlet preferences.
the getValues() and setValues() methods respectively.
Portlets have access to the PortletPreferences object when processing requests, but may only modify preference attributes during a processAction invocation. Prior to the end of the processAction method, the store()

JSP Tag Library
A JSP Tag library is included to help display portlet pages with JSP technology. For example, a custom JSP tag
automatically declares the portlet request and response objects so they can be used within the JSP. Another JSP tag
helps construct URL’s that refer back to the portlet.