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 support also led to using portal server–specific approaches to achieve communication between portlets, resulting in portability issues. This limitation in Portlet 1.0 made inter-portlet communication one of the highly anticipated features in Portlet 2.0.