Struts2+JSON+JQUERY DEMO

看到别人用了Struts2和JSON，自己也想练练手。记录下练习过程中遇到的问题，以便参考。

使用Maven新建项目：

先挂上pom.xml

 <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.sk</groupId>
     <artifactId>struts</artifactId>
     <packaging>war</packaging>
     <version>0.0.1-SNAPSHOT</version>
     <name>struts Maven Webapp</name>
     <url>http://maven.apache.org</url>
     <dependencies>
         <dependency>
             <groupId>junit</groupId>
             <artifactId>junit</artifactId>
             <version>3.8.1</version>
             <scope>test</scope>
         </dependency>
         <!-- Log -->
         <dependency>
             <groupId>org.apache.logging.log4j</groupId>
             <artifactId>log4j-api</artifactId>
             <version>2.0-beta7</version>
         </dependency>
         <dependency>
             <groupId>org.apache.logging.log4j</groupId>
             <artifactId>log4j-core</artifactId>
             <version>2.0-beta7</version>
         </dependency>

         <!-- Struts2 -->
         <dependency>
             <groupId>org.apache.struts</groupId>
             <artifactId>struts2-core</artifactId>
             <version>2.3.1.2</version>
         </dependency>
         <dependency>
             <groupId>org.apache.struts</groupId>
             <artifactId>struts-taglib</artifactId>
             <version>1.3.10</version>
         </dependency>

         <!-- servlet -->
         <dependency>
             <groupId>javax.servlet</groupId>
             <artifactId>servlet-api</artifactId>
             <version>2.5</version>
         </dependency>

         <!-- JSON LIB -->
         <dependency>
             <groupId>net.sf.json-lib</groupId>
             <artifactId>json-lib</artifactId>
             <version>2.2.3</version>
             <classifier>jdk15</classifier>
         </dependency>
         <!-- 如果缺少这个插件的话机会报: Unable to find parent packages json-default 这个错误折磨了我大半天，后来自己仔细看看tomcate启动日志发现了这个错误，经查询，是缺少了
             struts2-json-plugin-2.1.8.1.jar 这个包，因为struts2默认是以插件形式进行加载的，所以是少加载的json处理的包。加入这个包运行正常。如果没有这个包的话。
             运行时会报There is no Action mapped for namespace·······所有的Action都不能运行。 -->
         <dependency>
             <groupId>org.apache.struts</groupId>
             <artifactId>struts2-json-plugin</artifactId>
             <version>2.3.15</version>
         </dependency>

     </dependencies>
     <build>
         <plugins>
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-compiler-plugin</artifactId>
                 <version>3.0</version>
                 <configuration>
                     <source>1.7</source>
                     <target>1.7</target>
                 </configuration>
             </plugin>
         </plugins>
     </build>

 </project>

再整个VO：User.java

 package com.sk.struts2.bean;

 import java.io.Serializable;

 public class User implements Serializable {

     private String id;
     private String username;
     private String pwd;
         // 省略setter和getter
 }

然后是action：JSONAction.java

 package com.sk.struts2.action;

 import net.sf.json.JSONObject;

 import com.opensymphony.xwork2.ActionSupport;
 import com.sk.struts2.bean.User;

 public class JSONAction extends ActionSupport {

     private static final long serialVersionUID = -795596058695827298L;

     private User user;
     private String jsonString;

     @Override
     public String execute() throws Exception {
         JSONObject jsonObject = null;
         if(user != null){
             jsonObject = JSONObject.fromObject(user);
             jsonString = jsonObject.toString();
             System.out.println(jsonString);
         }
         return SUCCESS;
     }

     public User getUser() {
         return user;
     }

     public void setUser(User user) {
         this.user = user;
     }

     public String getJsonString() {
         return jsonString;
     }

     public void setJsonString(String jsonString) {
         this.jsonString = jsonString;
     }

 }

接着是View:json.jsp

 <%@ page language="java" contentType="text/html; charset=UTF-8"
     pageEncoding="ISO-8859-1"%>
 <%@ taglib prefix="s" uri="/struts-tags" %>
 <!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>Hello World!</title>
 <script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js"></script>
 <script type="text/javascript" src="<%= request.getContextPath() %>/resources/js/json.js"></script>
 </head>
 <body>
     <form>
         ID:<input type="text" name="user.id"/><br />
         username:<input type="text" name="user.username"/><br />
         pwd:<input type="text" name="user.pwd"/>

         <input id="btn" type="button" value="submit" />
     </form> 

     <h2>Here is result:</h2>
     <div id="result"></div>
 </body>
 </html>

还有JS:json.js

 $(function(){
     $('#btn').click(function(){
         var params=$("input").serialize();
         var actionPath = getRootPath() + "/jsonTest/jsonAction";

         $.ajax({
             url: actionPath,
             // 数据发送方式
             type: "post",
             // 接受数据格式
             dataType : "json",
             // 要传递的数据
             data : params,
             // 回调函数，接受服务器端返回给客户端的值，即result值
             success : show
         }).always(function(){alert('done');});
     });
 });

 function show(result){
     //测试result是否从服务器端返回给客户端
     //alert(result);
     //解析json对象
     var json = eval("("+result+")");
     var obj = "编号: "+json.id+"  用户名: "+json.username+"  密码: "+json.pwd;
     $("#result").html(obj);
 }

 //js获取项目根路径，如： http://localhost:8083/uimcardprj
 function getRootPath(){
     //获取当前网址，如： http://localhost:8083/uimcardprj/share/meun.jsp
     var curWwwPath=window.document.location.href;
     //获取主机地址之后的目录，如： uimcardprj/share/meun.jsp
     var pathName=window.document.location.pathname;
     var pos=curWwwPath.indexOf(pathName);
     //获取主机地址，如： http://localhost:8083
     var localhostPaht=curWwwPath.substring(0,pos);
     //获取带"/"的项目名，如：/uimcardprj
     var projectName=pathName.substring(0,pathName.substr(1).indexOf('/')+1);
     return(localhostPaht+projectName);
 }

最后奉上:struts.xml

 <?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>

     <constant name="struts.devMode" value="true" />

     <package name="test" namespace="/jsonTest" extends="json-default">
         <action name="jsonAction" class="com.sk.struts2.action.JSONAction">
             <result type="json">
                 <!-- 此处将reslut的值返回给客户端，root的值对应要返回的值的属性result.注意：root为固定写法，否则不会把result的值返回给客户端 -->
                 <param name="root">jsonString</param>
             </result>
         </action>
     </package>

 </struts>

ok,all done.下面测试哈：

最后给个目录结构：

OK.Enjoy!