Illinois Bio-Grid Portal Development

Overview

Portal Technologies

PDF available here.

Portlet Container

• Extension of the Servlet Container
• It handles portlet components in addition to servlet and JSP components
• It shares much of the servlet container functionality (HTTP request handling, web application context, classloaders, session management, security)

Portlets vs. Servlets -- Commonalities

• Portlets (as Servlets) are web components
  • can be packaged in the same WAR file
• Portlet API is modeled after Servlet API
• Portlets lifecycle is similar to Servlets lifecycle
  • (init, request processing, destroy)
• Portlets can include servlets and JSPs
  • JSR 168 specifies interoperablility requirements

Portlets vs. Servlets -- Differences

• Additional state
  • Portlet mode ("view", "configure", etc.)
  • Window state ("normal", "maximized", "print", etc.)
• Render parameters
  • Interaction state can be tracked across requests
  • Often more appropriate than using the session (anonymous user, back button, bookmarks)
• Portlet preferences
  • Persistent state that is managed by the portal
• Portlets share client request and response
  • Some operations are not allowed, e.g. setting response charset, string manipulation of URLs
• Requires a refined processing model
  • Two phases: processing and rendering
  • Processing takes place only when a user interacts with the portlet
  • Rendering takes place whenever a page with the portlet is shown

-- RobVogelbacher - 08 Jul 2005

• gridsphere.doc: http://140.192.37.11:18080/gridsphere