Lesson 1: Setting up webwork in a web application

For this lesson, you need to have a Servlet container set up and know how to create a web application. If you don't, we suggest you learn about Apache Tomcat, which is a free Servlet container from the Apache Jakarta Project, or Resin, from Caucho Technology, which is free for noncommercial use.

Notation Throughout these lessons, we'll assume that your web application root is the directory [webapp], and that your Java source files are kept in [src].

To install WebWork in a web application:

1. Download WebWork. The current version can be found at WebWork's home page. This tutorial is based on version 2.1.7.
2. Set up an empty web application. For example, if you are using Tomcat, this will have something like the following directories (the directory "webwork-lessons" is referred to as [webapp] in these lessons):

   [the tomcat root directory]
   \|_webapps
     \|_webwork-lessons
       \|_WEB-INF
         \|_classes
         \|_lib

3. Copy the required WebWork libraries to your web application:

• copy webwork-2.1.7.jar to [webapp]/WEB-INF/lib ,
• copy lib/core/*.jar to [webapp]/WEB-INF/lib (not to [webapp]/WEB-INF/lib/core).

1. Configure [webapp]/WEB-INF/web.xml, and create [webapp]/WEB-INF/classes/xwork.xml and [webapp]/WEB-INF/classes/validators.xml, as described below.

WebWork jar name If you have a later version of WebWork than 2.1.7, the WebWork jar will not be named webwork-2.1.7.jar. Be sure to replace all occurrences of this jar's name below with the name of the jar you are using.

web.xml:

Create the following web.xml file in [webapp]/WEB-INF. If you already have a web.xml file, just add the content of the <web-app> tag below to your existing <web-app> tag.

<?xml version="1.0"?>
<!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>
	<display-name>My WebWork Application</display-name>
	<servlet>
		<servlet-name>webwork</servlet-name>
		<servlet-class>com.opensymphony.webwork.dispatcher.ServletDispatcher</servlet-class>
		<load-on-startup>1</load-on-startup>
	</servlet>
	<servlet-mapping>
		<servlet-name>webwork</servlet-name>
		<url-pattern>*.action</url-pattern>
	</servlet-mapping>
	<taglib>
		<taglib-uri>webwork</taglib-uri>
		<taglib-location>/WEB-INF/lib/webwork-2.1.7.jar</taglib-location>
	</taglib>
</web-app>

This registers ServletDispatcher as a servlet, and maps it to the suffix *.action. We will go into this more in the section on Actions in the next lesson. WebWork's taglib descriptor allows WebWork tags to be used (see lesson 4.1).

Read more: web.xml

xwork.xml:

Create the following file xwork.xml in [webapp]/WEB-INF/classes/.

<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 1.0//EN" 
"http://www.opensymphony.com/xwork/xwork-1.0.dtd">

<xwork>
	<!-- Include webwork defaults (from WebWork JAR). -->
	<include file="webwork-default.xml" />
	
	<!-- Configuration for the default package. -->
	<package name="default" extends="webwork-default">
	</package>
</xwork>

For now, this xwork.xml does only two things:

• It informs WebWork that it should import the configuration information from webwork-default.xml. (This file is located at the root of the webwork-2.1.7.jar, so it is sure to be found.)

• It defines a default package (with the <package> section) where WebWork elements like actions, results and interceptors are registered.

Read more: xwork.xml

validators.xml:

Create a file validators.xml in [webapp]/WEB-INF/classes/ with the following content:

<validators> 
	<validator name="required"
		class="com.opensymphony.xwork.validator.validators.RequiredFieldValidator"/> 
	<validator name="requiredstring"
		class="com.opensymphony.xwork.validator.validators.RequiredStringValidator"/> 
	<validator name="int"
		class="com.opensymphony.xwork.validator.validators.IntRangeFieldValidator"/> 
	<validator name="date"
		class="com.opensymphony.xwork.validator.validators.DateRangeFieldValidator"/> 
	<validator name="expression"
		class="com.opensymphony.xwork.validator.validators.ExpressionValidator"/> 
	<validator name="fieldexpression"
		class="com.opensymphony.xwork.validator.validators.FieldExpressionValidator"/> 
	<validator name="email"
		class="com.opensymphony.xwork.validator.validators.EmailValidator"/> 
	<validator name="url"
		class="com.opensymphony.xwork.validator.validators.URLValidator"/> 
	<validator name="visitor"
		class="com.opensymphony.xwork.validator.validators.VisitorFieldValidator"/> 
	<validator name="conversion"
		class="com.opensymphony.xwork.validator.validators.ConversionErrorFieldValidator"/> 
</validators>

This file defines the validators used, for example, for validating html form fields.

Read more: Validation

All Set Up!

Restart your servlet container (for example, restart Tomcat), and your webapp should be ready for use as a skeleton WebWork application.

To test whether everything is working, create [webapp]/test.jsp:

<html>
<body>
Hello html world
<hr/>
<%
  out.println("Hello jsp world.");
%>
</body>
</html>

If you can load this file in your browser and see the two Hello messages, your web application is working.

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