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Preface

Struts Action Framework 2 is a popular, easy-to-use MVC framework. For more information on the SAF project, please visit the [SAF Project Home].
This document will help you to get started with the framework, enabling you to run the examples and demonstrations provided even if you are not an experienced Java web application developer. Nevertheless, the framework is geared towards developers that have an understanding towards certain technologies.

Before diving deeper into how the SAF works, it is recommended that you have some knowledge of the supporting technologies.

Supporting Technologies
  • Java
  • Servlets, JSP, and Tag Libraries
  • JavaBeans
  • HTML and HTTP
  • Web Containers (such as Tomcat)
  • XML

For more about any of the supporting technologies, visit the Key Technologies page on the Apache Struts website.

">Downloads and Resources

To get started with the framework, download the distribution and browse some of the online resources.

Download the Distribution

A release of SAF 2 may not yet be available.

The full distribution can be downloaded form the Apache Struts website. The distribution contains the struts-action2.jar file, a copy of all the documentation, sources, all [required and optional dependencies],and example applications. For more information on how to build the framework from source or even from a clean checkout, please refer to Building the Framework from Source.

Browse the Resources

There are many online resources available. Here are links to help you find your way:

Distribution Quickstart

Overview

The distribution contains the following directory layout:

dist/
docs/
lib/
src/
src/java/template/
webapps/
README.txt
build.properties
build.xml
ivy.xml
osbuild.xml
pom.xml
struts-action-(VERSION).jar
struts-action-(VERSION).zip
struts-action-(VERSION)-src.jar

The docs directory contains the current Javadocs, the full user documentation including the document you are reading, and taglib documentation, as well as Clover, JUnit and dependency reports for the build.

The dist directory contains framework files with different packaging:

  • struts-action-nostatic-<version>.jar: containing only the framework without the static content
  • struts-action-static-<version>.zip: containing the required framework static dependencies

The lib directory contains the required as well as optional [Dependencies] for the framework, organized in subdirectories to represent different optional configurations:

lib/
      ajax
      bootstrap
      build
      cewolf
      default
      fileupload
      fileupload-cos
      fileupload-pell
      hibernate
      jasperreports
      jfree
      pico
      plexus
      portlet
      quickstart
      sitemesh
      source
      spring
      tiger
      tiles
      velocity
      xslt

Note that none of the optional packages are required to use the framework. If you wish to use certain features such as JasperReports or Java 5 (Tiger) generics and annotation support, then you must include the optional packages.

The framework also comes packaged with all the source files and templates for the JSP tags.

">Running demos with QuickStart

The framework provides a slick way to jump into web development called QuickStart. Essentally, QuickStart is combination of technologies and conventions. The key technology is the ability to run web applications "out of the box" with a stripped-down Jetty container.

With QuickStart, running the demos is as easy as can be. You just need to run:

> java -jar webwork.jar quickstart:<application-name>

from the distribution's top directory, where <application-name> is one of the subdirectory names under webapps/. Each subdirectoy hosts a demo application.

If you want to start the shopping-cart webapp, the startup command would be:

> java -jar webwork.jar quickstart:shopping-cart

One the application starts up, point your browser to http://localhost:8080/shopping-cart/, and you should be ready to go.

Several example appliations are included in the distribution.

blank

Not really an example application, but a blank web application template to use as the base for your own applications

cookbook

A "how to" application that displays the full source code for each "recipe".

mailreader

The infamous Struts MailReader application.

portlet

Demonstration of our porlet integration (to be deployed in a Portal Server) - see [Portlet Tutorial] to read more about portlets

shopping-cart

Simple example application demonstrating various aspects of the framework

showcase

Extensive demonstration of all tag and AJAX features, along with other examples and some best practices

starter

Basic web application that you can use as a starting point for experimenting with framework features - one could almost call it a "playground" application

You can review the [QuickStart documentation] to learn more about how it works and how you can utilize QuickStart with your own applications.

See below for a more detailed description of how the blank application helps you to easily create your own WebWork-based applications.

">Running Demos with Your Favorite Web Container

In order to deploy applications and demos to your favorite servlet container (also called web container) such as Apache Tomcat or Caucho Resin, you will need to build WAR files from the webapps directory. You will find an Antbuild file there which will provide you with an easy way to build your own WARs.

To Quickstart or not to Quickstart?

Quickstart is a handy tool for development of your applications. We recommend that you give QuickStart a try, to see if it meets your development needs. However, QuickStart is not meant to be your sole environment for web application development. QuickStart is meant to help you rapidily create proof-of-concepts and so that you can see the result. We recommend you always at least test your work under other applications servers, such as Tomcat, Resin, or even the standard, standalone version of Jetty.

To build a web application archive (WAR), simply run:

> ant build -Dwebapp=$APP

where $APP is the name of the web application you want to build. After the build is finished, the fully-built WAR file can be found in the dist directory. You may deploy this file to any servlet container.

To build the {{showcase}] aplication, substite "showcase" for $ID.

> ant build -Dwebapp=showcase

To deploy the built showcase.war to Tomcat, move or copy the WAR to $TOMCAT_HOME/webapps/ or use the Tomcat Manager Application to upload and deploy the WAR. After the WAR is deployed (and your server is started), point your browser to

> http://localhost/showcase

Of course, if the server is not local, substitute the IP or hostname for "localhost", including a port designation if needed. If you are not deploying the Showcase application, then substitute the appropriate application name for "showcase"

Deploying the Examples

The framework build copies the sources of each bundled web application to dist/webapps/$APP. The build also compiles the sources for each appolication and creates a WAR at dist/webapps/$APP.war. However, these WAR files are NOT ready to be deployed. These WARs do not include any of the JAR files. (Omitting the JARS reduces the size of the download by almost 200mb.) To include the dependant JARs, run Ant in the dist/webapps directory, and new WARs, with all the JARs, are placed in dist/webapps/dist.

">Your First SAF2 Application

To get started on your own application, you can utilize the blank template, run the Ant task, or just setup your own from scratch.

Using the Blank template

The blank web application in the distribution's

Unknown macro: {webapp}

directory is meant as a template. Make a copy of "blank" and use the copy as the basis for your application.

Run the Ant task

While it's simple enough to copy a directory tree, there is an even easier way to get started. In the webapps directory, there is a build.xml file. The new task of this Ant build file can create fresh, empty web application for you. Just add content!

> cd /projects/Apache/struts-current/action2/webapps
> ant new

The Ant buildfile will prompt you for a the name of your new application.

Setting up from Scratch

If for some reason the blank template doesn't work for you, it's not so hard to setup a SAF-based application from scratch.

Structure of your web application

  • Setup a file structure for your application.
/mywebapp/
/mywebapp/template/
/mywebapp/META-INF/
/mywebapp/WEB-INF/
/mywebapp/WEB-INF/classes/
/mywebapp/WEB-INF/lib/
/mywebapp/WEB-INF/lib/CORE&OPTIONAL *.jar
/mywebapp/WEB-INF/web.xml
  • Copy to your webapp/lib directory
    • the struts-action-(VERSION).jar,
    • all the *.jar files in /lib/default,
    • and any necessary optional {{*.jar} files in {{/lib/(optional configuration) }}.

If you need to customize your own templates (how HTML is rendered from webwork UI tags), copy into your webapp/ directory the /src/java/template directory.

Minimum Set of Libraries and Config Files

The following files are a minium requirement for your application.

Filename

Description

struts-action.jar

Framework library itself, found in distribution root directory

xwork.jar

XWork library on which WebWork is built

oscore.jar

OSCore, a general-utility library from OpenSymphony

ognl.jar

Object Graph Navigation Language (OGNL), the expression language used throughout the framework

commons-logging.jar

Commons logging, which WebWork uses to support transparently logging to either Log4J or JDK 1.4+

freemarker.jar

All UI tag templates are written in Freemarker, which is also a good option for your views

spring*.jar

The default dependency injection container for the framework.

web.xml

J2EE web application configuration file that defines the servlets, JSP tag
libraries, and so on for your web application

action.xml

WebWork configuration file that defines the actions, results, and interceptors for your application

The library files (*.jar) needs to be copied to your /mywebapp/WEB-INF/lib/ directory. If you need optional functionalities requiring dependencies on optional JARs, those JARs need to be copied to this directory too.

web.xml

Create an web.xml file in [webapp]/WEB-INF (or merge into it the framework resources).

web.xml
<?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 Application</display-name>
  <filter>
    <filter-name>action2</filter-name>
    <filter-class>org.apache.struts.action2.dispatcher.FilterDispatcher</filter-class>
  </filter>

  <filter-mapping>
    <filter-name>action</filter-name>
    <url-pattern>/*</url-pattern>
  </filter-mapping>
  <listener>
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
  </listener>
</web-app>

The standard{{web.xml} registers FilterDispatcher to enable framework functionality for your requests. The ContextLoaderListener set ups [Spring] as our dependency injection conitainer. The framework uses Spring internally, and you may wish to use it to deploy your own objects.

See also: web.xml

action.xml

Create a skeleton {[action.xml}} file in /$APP/WEB-INF/classes/.

action.xml
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 1.1.1//EN"
"http://www.opensymphony.com/xwork/xwork-1.1.1.dtd">

<xwork>	<!-- Include framework defaults (from Struts Action JAR). -->
	<include file="action-default.xml" />

	<!-- Configuration for the default package. -->
	<package name="default" extends="action-default">
	</package>
</xwork>

For now, the action.xml does only two things:

  • It tells the framework that it should import the configuration information from action-default.xml. (This file is located at the root of the struts-action.jar, so it is sure to be found.)
  • It defines a default package (with the <package> section) where framework elements like actions, results and interceptors are registered.

See also: [action.xml]

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