Portlets
A nice article explaining how to develop Portlets using Sun Java Studio can be founded here.
In 2003, two important standards emerged to address reuse and content portability: Web Services for Remote Portlets Specification (WSRP) and Java Specification Request 168 Portlet Specification (JSR 168). At first glance, both WSRP and JSR 168 may seem to be competing or overlapping standards. In reality, even though they overlap in a few areas and complement each other. This article describes how to use Studio Enterprise 6 2004Q1 to create a portlet-an integration component between an application and your portal- that complies with Java Specification Request 168 Portlet Specification (JSR 168) to access the Google Web service.