Portlet specification 2.0 Proposed Final draft is out for documentation.

A Quick look at the major changes that you will find in the JSR 286 are:-

- Event bus concept for Interportlet Communication ( In JSR 168 we use PortletSession with APPLICAION_SCOPE for IPC )which will allow portlets in two different war to communicate each other.

- Render parameter sharing will allows to share render parameters with portlets.

- Portlet Filter

- New request type introduced.Event Request, Resource Request, Fragmanet Request.

- creating different url like createFragementURL, createRresourceURL by invoking methods on portletResponse interface.

- Security

- Caching.

and many more....

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