IBM WebSphere Portal 7 API and SPI Reference
The WebSphere Portal programming model is an extension of the J2EE programming model. Developers use it to implement Web applications that leverage the rich set of WebSphere Portal platform capabilities. Capabilities include aggregation and integration of components into page hierarchies, flexible navigation, content and application aggregation, branding, customization, personalization, content management, document management, search, and so on.
The WebSphere Portal programming model consists of various APIs, SPIs, JSP Taglibs, Eclipse plug-points, and descriptors that let you customize the aggregation steps at different levels.