Portlets in Action

Chapter 11. Communicating with other portlets

This chapter covers

• Inter-portlet communication using portlet sessions
• Public render parameters
• Portlet events
• Portlet event support in Spring Portlet MVC
• Pros and cons of different approaches to inter-portlet communication

In 2003, when Portlet 1.0 (JSR 168) was released, it didn’t define support for communication between portlets. The only way to achieve inter-portlet communication in the Portlet 1.0 days was by using PortletSession, which required communicating portlets to reside in the same portlet application. If you wanted a third-party portlet to communicate with your custom portlet, you had to package them as part of a single portlet application.

The lack of inter-portlet communication ...