WebSphere Portal Express and Express Plus V5 for the IBM eServer iSeries Server

268 WebSphere Portal Express and Express Plus V5 for the IBM Eserver iSeries Server

7.1 A portal and portlet overview

This section introduces a general overview of portal and portlets and defines brief concepts

and terminologies about portal.

7.1.1 Portal

A portal is generally synonymous with a gateway for a World Wide Web site. It is a major

converging point that offers a single point of personalized interaction with applications,

content, processes, and people to provide a unified user experience. Portals are divided into

two categories: general purpose portal and specialized portal. Some major general purpose

portals include IBM, Yahoo, Excite, and America Online’s AOL.com. Examples of specialized

portals include Garden.com, and Fool.com (for investors).

Many successful companies allow access to their company portal through the Web for their

own users, customers, and business partners. Typical services offered by a portal include:

򐂰 Integrated seamless access to disparate applications through the use of single signon

(SSO)

򐂰 Team collaboration

򐂰 Team e-meeting

򐂰 Support for pervasive devices

򐂰 Syndicated news

򐂰 Document Management and workflow

򐂰 Weather information

򐂰 Access to e-mail

򐂰 Stock quotes

򐂰 Employee phone directory

Some of these portal features, such as weather, news, stocks, and bookmarks, are shown in

the sample portal home page (Figure 7-1).

Chapter 7. iSeries portlets 269

Figure 7-1 Sample portal home page

7.1.2 Portlet

From a user’s perspective, a portal is like a television which broadcasts specialized programs

on specific television channels-portlets. From an application development perspective,

portlets are pluggable components that run inside a portlet container of a portal server

instance. Portlets are shared components that provide access to Web-based applications,

contents, and other portal resources.

A portlet container manages a runtime life cycle in which portlets are created, used, and then

destroyed. A portlet container is not a stand-alone container such as servlet container. It is

implemented as a thin layer on top of the servlet container. Its function is to reuse the services

provided by the servlet container. A portlet container relies on the Java 2 Platform, Enterprise

Edition (J2EE) architecture implemented by WebSphere Application Server.

Every portlet has to inherit from the abstract org.apache.jetspeed.portlet.Portlet class, either

by deriving directly from it or by using one of the abstract portlet implementations or

PortletAdapter. Unlike servlets, portlets cannot send redirect or error messages to browsers

directly, forward requests, or write arbitrary markup to the output stream. Portlets can be

administered dynamically using the portal administration interface provided by WebSphere

Portal.

Standard portlet

The portlets shown in Table 7-1, Table 7-2, and Table 7-3 are available with WebSphere

Portal. They are located in wp_root/InstallableApps directory, where wp_root is the root

directory for the WebSphere Portal server instance. For example, if your instance’s name is

myPortal, then the root directory is /QIBM/UserData/WebAS5/Base/myPortal/

PortalServer5/installableApps.