A portlet is a Java technology-based web component. It is managed by the portlet container and
processes requests and generates dynamic content as response. Portlets are used by portals as
pluggable user interface components.
The content generated by a portlet is called a fragment. A fragment is a piece of
markup (e.g. HTML, XHTML, WML) adhering to certain rules and can be aggregated
with other fragments into a complete document. The content of a portlet is normally
aggregated with the content of other portlets into the portal page.
The portlet container instanciates portlets, manages their lifecycle
and invoking them to process requests. The lifecycle consists of:
Request processing is divided into two types: