Converting Channels to Portlets

If you have an existing IChannel which you'd like to rewrite as a portlet, a number of concepts need to be re-mapped.

IChannel Metaphor	Portlet Equivalent	Notes
RenderXML()	processAction(), render()	In IChannel the main method to display content is renderXML(). Portlets have a 2-phase lifecycle expressed via the processAction() and render() methods. This lifecycle is intended to: #separate state-changing operations from non-state changing #allow for lightweight, highly performant render() calls
IPerson	USER_INFO	Portlets provide a standard convention for getting user attributes by calling requres.getAttribute(USER_INFO) which returns a map of configured user attributes, mapped against PersonDirectory (in uPortal) via portlet.xml
deployment to uPortal/WEB-INF/classes	deployment as a WAR file	Portlets are typically packaged as separate web applications from the Portal server, and deployed using a special tool (in uPortal's case the deployPortletApp ANT target