SSH构造struts2项目

第一在pom.xml导入相应的包

（网上有很多导入多个包的教程，我缩减到一个了）

 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
     <modelVersion>4.0.0</modelVersion>
     <groupId>com.lgp</groupId>
     <artifactId>maven_struts2</artifactId>
     <packaging>war</packaging>
     <version>0.0.1-SNAPSHOT</version>
     <name>maven_struts2 Maven Webapp</name>
     <url>http://maven.apache.org</url>
     <properties>
         <project.build.sourceEncoding>
             UTF-8
         </project.build.sourceEncoding>
     </properties>

     <dependencies>
         <dependency>
             <groupId>junit</groupId>
             <artifactId>junit</artifactId>
             <version>3.8.1</version>
             <scope>test</scope>
         </dependency>
         <dependency>
             <groupId>org.apache.struts</groupId>
             <artifactId>struts2-core</artifactId>
             <version>2.3.31</version>
         </dependency>
     </dependencies>
     <build>
         <finalName>maven_struts2</finalName>
     </build>
 </project>

导入包之后，有的电脑会报错，maven-update就好了

然后去web.xml那里注册struts2的过滤器

 <!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>Archetype Created Web Application</display-name>
     <filter>
         <filter-name>struts2</filter-name>
         <filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter</filter-class>
     </filter>

     <filter-mapping>
         <filter-name>struts2</filter-name>
         <url-pattern>/*</url-pattern>
     </filter-mapping>
 </web-app>

然后就写struts.xml，记住放在resources文件夹下

 <?xml version="1.0" encoding="UTF-8" ?>
 <!DOCTYPE struts PUBLIC
     "-//Apache Software Foundation//DTD Struts Configuration 2.0//EN"
     "http://struts.apache.org/dtds/struts-2.0.dtd">

 <struts>
     <!-- name:包名,可自定义 extends：继承 namespace:命名空间 -->
     <!-- 定义常量 请求后缀 默认是.action -->
     <!-- 但指定了之后 就必须写上后缀 -->
     <constant name="struts.action.extension" value="action,do" />
     <package name="helloworld" extends="struts-default" namespace="/">
         <action name="helloworld_*" class="com.action.HelloWorldAction"
             method="{1}">
             <result name="{1}">{1}.jsp</result>
         </action>
     </package>
     <package name="user" namespace="/" extends="struts-default">
         <interceptors>
             <interceptor name="myInterceptor" class="com.interceptor.MyInterceptor"></interceptor>
             <interceptor-stack name="mystack">
                 <interceptor-ref name="defaultStack" />
                 <interceptor-ref name="myInterceptor" />
                 <!-- 先进入默认拦截器，再到自定义拦截器 -->
             </interceptor-stack>
         </interceptors>
         <action name="user_login" class="com.action.UserAction" method="login">
             <interceptor-ref name="mystack"></interceptor-ref>
             <result name="success">userinfo.jsp</result>
         </action>
     </package>
 </struts>

action类

 package com.action;

 public class HelloWorldAction {
     public String a() {
         System.out.println("a..");
         return "a";
     }

     public String b() {
         System.out.println("b..");
         return "b";
     }

     public String c() {
         System.out.println("c..");
         return "c";
     }

     public String user() {
         System.out.println("user..");
         return "user";
     }
 }

 package com.action;

 import com.entiy.User;
 import com.opensymphony.xwork2.ActionContext;
 import com.opensymphony.xwork2.ActionSupport;
 import com.opensymphony.xwork2.util.ValueStack;

 public class UserAction extends ActionSupport {
     private static final long serialVersionUID = -1417237614181805435L;
     private String name;
     private String pwd;

     public String login() {
         System.out.println("login..");
         System.out.println("name----" + name);
         System.out.println("pwd----" + pwd);
         // ValueStack vs=ActionContext.getContext().getValueStack();
         ActionContext context = ActionContext.getContext();
         ValueStack vs = context.getValueStack();
         // 值栈的栈顶

         User user = new User("张三", "张三的密码");
         vs.push(user);
         return SUCCESS;
     }

     public String getName() {
         return name;
     }

     public void setName(String name) {
         this.name = name;
     }

     public String getPwd() {
         return pwd;
     }

     public void setPwd(String pwd) {
         this.pwd = pwd;
     }
 }

实体类

 package com.entiy;

 public class User {
     private String name;
     private String pwd;

     public User(String name, String pwd) {
         this.name = name;
         this.pwd = pwd;
     }

     public String getPwd() {
         return pwd;
     }

     public void setPwd(String pwd) {
         this.pwd = pwd;
     }

     public String getName() {
         return name;
     }

     public void setName(String name) {
         this.name = name;
     }
 }

拦截器

 package com.interceptor;

 import com.opensymphony.xwork2.ActionInvocation;
 import com.opensymphony.xwork2.interceptor.AbstractInterceptor;

 /**
  * 自定义拦截器
  *
  * @author SUMMER
  *
  */
 public class MyInterceptor extends AbstractInterceptor {

     /**
      *
      */
     private static final long serialVersionUID = 1L;

     /**
      * 判断session有关的操作
      */
     @Override
     public String intercept(ActionInvocation actioninvocation) throws Exception {
         System.out.println("我的拦截器开始...");
         actioninvocation.invoke();
         System.out.println("我的拦截器结束...");
         // AOP 面向切面编程
         return null;
     }

 }

a.jsp/b.jsp/c.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
aaaaaaaaaaaaaaaa
</body>
</html>

index.jsp

a没有后缀所以是错误的

 <%@ page language="java" contentType="text/html; charset=UTF-8"
     pageEncoding="UTF-8"%>
 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
 <html>
 <head>
 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>Insert title here</title>
 </head>
 <body>
    <a href="<%=request.getContextPath() %>/helloworld_a">a</a>
    <br><br>
    <a href="<%=request.getContextPath() %>/helloworld_b.do">b</a>
    <br><br>
    <a href="<%=request.getContextPath() %>/helloworld_c.action">c</a>
    <br><br>
    <a href="<%=request.getContextPath() %>/helloworld_user.action">用户</a>
 </body>
 </html>

user.jsp/userinfo.jsp

姓名分成3组

第二第三组是一对的，第一是混搭的，注意取值的方法

 <%@ page language="java" contentType="text/html; charset=UTF-8"
     pageEncoding="UTF-8"%>
 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
 <html>
 <head>
 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>Insert title here</title>
 </head>
 <body>
 <form action="<%=request.getContextPath() %>/user_login.do" method="post">
     姓名:<input type="text" name="name">
     <br><br>
     密码:<input type="text" name="pwd">
     <br><br>
     <input type="submit" value="登录">
 </form>
 </body>
 </html>

 <%@ page language="java" contentType="text/html; charset=UTF-8"
     pageEncoding="UTF-8" isELIgnored="false"%>
 <%@taglib uri="/struts-tags" prefix="s"%>
 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
 <html>
 <head>
 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>Insert title here</title>
 </head>
 <body>
     姓名1:${name}
     <br>密码1:<%=request.getParameter("pwd")%><br>
     <br>姓名2:
     <s:property value="[0].name" />
     <br>密码2:${requestScope.pwd}
     <br>姓名3:
     <s:property value="[1].name" />
     <br>密码3:
     <s:property value="[1].pwd" />
     <br>
 </body>
 </html>