WebWork Portlet Tutorial

In Progress

This is a work in progress. Thank you for your patience.

Index

Introduction

This tutorial walks you through the process of building a simple portlet application, using Eclipse, JBoss Portal 2.2 and the WebWork Portlet framework.

Installing Eclipse

In the tutorial, we will be using Eclipse 3.1.1 which can be downloaded from http://www.eclipse.org

Preparations

A Portlet application is basically packaged as a regular web application, but with an additional descriptor; portlet.xml. The first step of the tutorial is to create the project structure in eclipse. First, let's create the Java project itself using the new project wizard. We call the project 'MyPortlet'. Make sure to select the "Create separate source and output folders" radio button, and hit "next". In the next wizard step, set the output folder for the 'src' source folder to 'MyPortlet/webapp/WEB-INF/classes'. This makes sure it will be easy for us to export the application as a WAR file when we're done.

New project wizard

New project wizard, cont

Classpath settings

Before buliding the application itself, we need to add some required jar files to the build classpath and the WEB-INF/lib folder. Firstly, create the WEB-INF/lib folder and download the WebWork 2.2.1 distribution and unzip it to your local harddrive. Locate the jar files shown in the screenshot and and put them in the newly created WEB-INF/lib folder. Select all the jar files, and right click and select "Build Path -> Add to Build Path". Now your local project should look similar to the screenshot.

portlet.xml

Next thing we do is create a portlet.xml file in the WEB-INF folder. In this file, write the following:

<portlet-app version="1.0" xmlns="http://java.sun.com/xml/ns/portlet/portlet-app_1_0.xsd"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/portlet/portlet-app_1_0.xsd http://java.sun.com/xml/ns/portlet/portlet-app_1_0.xsd">
  <portlet>
    <description xml:lang="EN">My very first WebWork Portlet</description>
    <portlet-name>MyPortlet</portlet-name>
    <display-name xml:lang="EN">My first WebWork Portlet</display-name>
    
    <portlet-class>com.opensymphony.webwork.portlet.dispatcher.Jsr168Dispatcher</portlet-class>

    <init-param>
      <!-- The view mode namespace. Maps to a namespace in the xwork config file -->
      <name>viewNamespace</name>
      <value>/view</value>
    </init-param>
    <init-param>
      <!-- The default action to invoke in view mode -->
      <name>defaultViewAction</name>
      <value>index</value>
    </init-param>

    <expiration-cache>0</expiration-cache>

    <supports>
      <mime-type>text/html</mime-type>
    </supports>

    <supported-locale>en</supported-locale>

    <portlet-info>
      <title>My very own WebWork Portlet</title>
      <short-title>WWPortlet</short-title>
      <keywords>webwork,portlet</keywords>
    </portlet-info>
  </portlet>
</portlet-app>

This portlet.xml file sets up the portlet using the com.opensymphony.webwork.portlet.dispatcher.Jsr168Dispatcher Portlet implementation. It also tells the Portlet that it will map the view portlet mode to a /view namespace in the XWork configuration, which we must remember when building our XWork actions. In addition, it tells the portlet that if it does not find an action parameter in the portlet request, the default action to invoke is the "index" action, which
should reside in the /view namespace in our xwork configuration.

web.xml

The WebWork Portlet support also requires you to include a web.xml descriptor that sets up some special servlets and filters needed to enable support for the WebWork tag libraries and template languages, since it relies on some of the interfaces and classes in the Servlet API. So create a web.xml file in the WEB-INF folder, and add the following:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE web-app PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN" "http://java.sun.com/dtd/web-app_2_3.dtd">
<web-app>
	<filter>
		<filter-name>webwork</filter-name>
		<filter-class>
			com.opensymphony.webwork.dispatcher.FilterDispatcher
		</filter-class>
	</filter>

	<filter-mapping>
		<filter-name>webwork</filter-name>
		<url-pattern>/*</url-pattern>
	</filter-mapping>

	<listener>
		<listener-class>
			com.opensymphony.webwork.portlet.context.ServletContextHolderListener
		</listener-class>
	</listener>


	<servlet>
		<servlet-name>preparator</servlet-name>
		<servlet-class>
			com.opensymphony.webwork.portlet.context.PreparatorServlet
		</servlet-class>
	</servlet>

	<taglib>
		<taglib-uri>/webwork</taglib-uri>
		<taglib-location>/WEB-INF/lib/webwork-2.2.1.jar</taglib-location>
	</taglib>

</web-app>

Child pages

Portlet Tutorial