[Struts2学习笔记] -- 环境配置

　　在创建好WebProject后，就可以开始进行Struts2的环境配置，可以到Struts2官网下载，本环境使用struts-2.3.24.1版本。

　　首先导入必要的jar包到WebProject的/WebRoot/WEB-INF/lib下，具体jar包如下图所示：

　　接着修改web.xml文件，加入struts2的配置信息，文件内容如下：

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd" id="WebApp_ID" version="3.1">  
  <display-name>myStruts2</display-name>
  <!-- struts2 configuration -->
  <filter>
      <filter-name>struts2</filter-name>
      <filter-class>
          org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter
      </filter-class>
      <init-param>
        <param-name>actionPackages</param-name>
        <param-value>cn.net.bysoft</param-value>
    </init-param>
  </filter>
  <filter-mapping>
      <filter-name>struts2</filter-name>
      <url-pattern>/*</url-pattern>
  </filter-mapping>
</web-app>

web.xml的配置

　　现在struts2的环境配置已经建立完毕，可以编写一个HelloWorld应用进行测试了，首先创建两个jsp页面，一个是index.jsp，里面写一个<a href="helloWorld">测试HelloWorld应用</a>连接到Action。接着创建一个hello.jsp页面用来显示<h1>Hello World</h1>，具体代码如下：

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>
    <base href="<%=basePath%>">
    
    <title>My JSP 'index.jsp' starting page</title>
    <meta http-equiv="pragma" content="no-cache">
    <meta http-equiv="cache-control" content="no-cache">
    <meta http-equiv="expires" content="0">    
    <meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
    <meta http-equiv="description" content="This is my page">
    <!--
    <link rel="stylesheet" type="text/css" href="styles.css">
    -->
  </head>
  
  <body>
    <a href="helloWorld">test helloworld</a>
  </body>
</html>

index.jsp

<%@ page language="java" import="java.util.*" pageEncoding="ISO-8859-1"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>
    <base href="<%=basePath%>">
    
    <title>My JSP 'hello.jsp' starting page</title>
    
    <meta http-equiv="pragma" content="no-cache">
    <meta http-equiv="cache-control" content="no-cache">
    <meta http-equiv="expires" content="0">    
    <meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
    <meta http-equiv="description" content="This is my page">
    <!--
    <link rel="stylesheet" type="text/css" href="styles.css">
    -->

  </head>
  
  <body>
    HelloWorld <br>
  </body>
</html>

hello.jsp

　　页面创建完毕后，开始编写Action类，创建一个普通的类，继承ActionSupport类。编写execute()方法进行页面控制，返回一个成功的标识SUCCESS，具体代码如下：

package cn.net.bysoft;

import com.opensymphony.xwork2.ActionSupport;

public class HelloWorldAction extends ActionSupport {

    /**
     * 
     */
    private static final long serialVersionUID = 6649419922238488318L;

    @Override
    public String execute() throws Exception {
        // TODO Auto-generated method stub
        return SUCCESS;
    }
    
}

HelloWorldAction的代码

　　最后在/src目录下创建一个struts.xml文件，对我们编写的Action进行配置，文件内容如下：

<!DOCTYPE struts PUBLIC "-//Apache Software Foundation//DTD Struts Configuration 2.3//EN" "http://struts.apache.org/dtds/struts-2.3.dtd">
<struts>
    <package name="struts2_3_24_1" extends="struts-default">
        <action name="helloWorld" class="cn.net.bysoft.HelloWorldAction">
            <result>/hello.jsp</result>
        </action>
    </package>
</struts>

struts.xml的内容

　　以下是项目结构：