Sample Desktop and Desktop Hierarchy

The sample desktops use an aggregation of a variety of separate web applications (channels) within a common framework. The common framework provides multiple levels and styles of aggregation, presented to end users through a container metaphor.

Providers and Channels

In the Desktop, leaf channels are the basic unit of content, displaying a specific type of information. To the end user, a channel is a distinct unit of content in the Desktop, usually (but not always) set off with a border and header row of icons that enables users to configure the channel to their preference. A provider is a Java^TM class responsible for converting the content, from a file or an application or service, into a presentable format for a channel.

Portlets and Web Service for Remote Portlets

Portlets and Web Service for Remote Portlets (WSRP) are available with Portal Server. Portlets are web components specifically designed to be aggregated in the context of a composite page. Java Specification Request (JSR) 168 specifies how portlets interact, how their life cycles are managed, and provides details of their semantics.

WSRP provides a presentation-oriented web service. A presentation-oriented web service returns the headers formatted through markup and ready for display in a web browser.

Portal Server Software Desktop

The Desktop provides a mechanism for extending and aggregating content through the Provider Application Programming Interface (PAPI). The PAPI is a Java^TM API that enables you to construct the basic building blocks for creating channels. Usually, though not always, channels contain content. You can also have channels of channels; that is, a container channel that aggregates other channels. A channel can also be the entire Desktop page. The container channels define the layout of the Desktop.

See Sample Desktop and Desktop Hierarchy for a simple representation of a portal Desktop and its providers and containers. In this figure, the Desktop front page is a tab container with two tabs. Each tab contains a table container with various channels.

Notice how one provider, in this case, URLScraperProvider, is serving more than one channel. Providers can have a one-to-many relationship with channels.

Figure 1–1 Desktop Hierarchy and Building Block Providers