1.搭建第一个struts2 app.
web.xml
1 <?xml version="1.0" encoding="UTF-8"?> 2 <web-app version="2.5" 3 xmlns="http://java.sun.com/xml/ns/javaee" 4 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 5 xsi:schemaLocation="http://java.sun.com/xml/ns/javaee 6 http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"> 7 <welcome-file-list> 8 <welcome-file>index.jsp</welcome-file> 9 </welcome-file-list> 10 11 <filter> 12 <filter-name>struts2</filter-name> 13 <filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter</filter-class> 14 </filter> 15 16 <filter-mapping> 17 <filter-name>struts2</filter-name> 18 <url-pattern>/*</url-pattern> 19 </filter-mapping> 20 21 </web-app>
注：struts1框架由servlet启动，strust2框架由filter启动
struts.xml
1 <?xml version="1.0" encoding="UTF-8" ?> 2 <!DOCTYPE struts PUBLIC 3 "-//Apache Software Foundation//DTD Struts Configuration 2.0//EN" 4 "http://struts.apache.org/dtds/struts-2.0.dtd"> 5 6 <struts> 7 <!-- Add packages here --> 8 <package name="alibaba" extends="struts-default" namespace="/alibaba"> 9 <action name="helloWorld" method="excute" class="com.alibaba.struts2.HelloWorld"> 10 <result name="success">/WEB-INF/page/helloWorld.jsp</result> 11 </action> 12 </package> 13 </struts>
注：extends="struts-default"，是关键。使用struts2框架核心功能，比如说文件上传等。需要继承struts2-default 这个包
在struts-default.xml文件中可以看到
1 <package name="struts-default" abstract="true"> 2 .... 3 <interceptor name="alias" class="com.opensymphony.xwork2.interceptor.AliasInterceptor"/> 4 .....
拦截器是struts的核心。
action
1 package com.alibaba.struts2; 2 3 public class HelloWorld 4 { 5 6 private String msg; 7 8 public String getMessage() 9 { 10 return msg; 11 } 12 13 public String excute() 14 { 15 this.msg = "Hello,This is my frist struts2 app."; 16 return "success"; 17 } 18 19 }
jsp
1 <%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%> 2 3 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> 4 <html> 5 <head> 6 <title>My JSP 'helloWorld.jsp' starting page</title> 7 8 <meta http-equiv="pragma" content="no-cache"> 9 <meta http-equiv="cache-control" content="no-cache"> 10 <meta http-equiv="expires" content="0"> 11 <meta http-equiv="keywords" content="keyword1,keyword2,keyword3"> 12 <meta http-equiv="description" content="This is my page"> 13 <!-- 14 <link rel="stylesheet" type="text/css" href="styles.css"> 15 --> 16 17 </head> 18 19 <body> 20 ${message} 21 </body> 22 </html>
注：EL表达式中的参数和action中的getMessage()中的Message要一致。