Strut2中的session和servlet中的session的区别

在jsp中，内通过内置对象 HttpServletRequest的getSession()方法可以获取到HttpSession，比如：

 1 <%@ page language="java" contentType="text/html; charset=UTF-8"
 2     pageEncoding="UTF-8"%>
 3 <%@taglib uri="http://www.wyl.suneyaee" prefix="Wyl"%>
 4 <!-- 引入jquery等 -->
 5 <%@ include file="/WEB-INF/head.jsp"%>
 6 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
 7 <html>
 8 
 9 <head>
10 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
11 <script type="text/javascript">
12 <!--
13     $(function() {
14         $('input').keydown(function(e) {
15             var curKey = e.which;
16             //46 是 Delete键
17             if (curKey == 46) {
18                 clear(this);
19                 $(this).focus();
20             }
21         });
22 
23         $('#idUserName').keydown(function(event) {
24             var curKey = event.which;
25             //13 是回车键
26             if (curKey == 13) {
27                 console.log('你按的是：回车' + '键');
28             }
29 
30         });
31         /**
32             清除value值，主要是针对于input
33          */
34         function clear(obj) {
35             $(obj).attr('value', null);
36         }
37     })
38 </script>
39 
40 <title>Insert title here</title>
41 </head>
42 <body>
43 <Wyl:getIP />
44 
45 <form action="doAjax"><input value="aaa" type="text"> <br>
46 <input value="doAJax" type="submit"></form>
47 
48 <br>
49 <form action="wdAjax"><input value="MyAjax.myAjax()..."
50     type="text"> <br>
51 <input value="wdAjax" type="submit"></form>
52 
53 <br>
54 用户名
55 <form action="toLogin"><input type="text" name="user.userName">
56 <br>
57 <%
58     request.getSession().setAttribute("hahaAnyKey", "我是hahaAnyKey.jsp页面传入session的值");
59 %>
60 <input type="text" name="user.passWord"> <input type="submit">
61 </form>
62 
63 
64 <br>
65 用户名2 ，模型驱动，而且这个表单对应的LoginAction2.java中封装了dto,而且可以使用Delete键清空输入框
66 <form action="toLogin2"><input type="text" name="userName"
67     id="idUserName"> <br>
68 <input type="text" name="passWord"> <input type="submit">
69 </form>
70 
71 -----------
72 <span xmlns="http://www.w3.org/1999/xhtml"
73     class="button collapse-button"></span>
74 
75 </body>
76 </html>

中的58行，就可以获取到session，然后直接在HttpSession里存放一个值。

而在Struts2中，比如在一个action中，可以直接通过ActionContext.getContext().getSession()获取Session对象(注意：这个ActionContext是

...ActionContext类型的)，实际上这里的Session是一个Mapper,只是Struts2做了封装，我们还是可以通过这个mapper类型的Mapper来获取到上面登录页面放在HttpSession中的属性。

比如在一个action中就可以通过如下代码获取到上面jsp中存放在HttpSession中的属性，

1 ActionContext atx = ActionContext.getContext();
2             Map<String, Object> session = atx.getSession();
3             Set<String> set = session.keySet();
4             Iterator it =  set.iterator();
5             while(it.hasNext()){
6                 String key = (String) it.next();
7                 String val = (String) session.get(key);
8                 System.out.println("key:"+key+",value:"+val);
9             }

打印结果：

key:hahaAnyKey,value:我是hahaAnyKey.jsp页面传入session的值

这个Action的完整代码如下：

 1 package com.log;
 2 
 3 import java.io.PrintWriter;
 4 import java.util.Iterator;
 5 import java.util.Map;
 6 import java.util.Set;
 7 
 8 import javax.servlet.http.HttpServletResponse;
 9 
10 import org.apache.struts2.ServletActionContext;
11 
12 import com.log.entity.User;
13 import com.log.service.UserService;
14 import com.opensymphony.xwork2.ActionContext;
15 import com.opensymphony.xwork2.ActionSupport;
16 import com.util.UtilTime;
17 
18 /**
19  * 普通的登陆
20  * 
21  * @author Wei
22  * 
23  */
24 public class LoginAction extends ActionSupport {
25     /**
26      * 
27      */
28     private static final long serialVersionUID = 1L;
29     private User user;
30     private UserService uService = new UserService();
31     private String error;
32 
33     public String getEror() {
34         return error;
35     }
36 
37     public void setEror(String error) {
38         this.error = error;
39     }
40 
41     public UserService getuService() {
42         return uService;
43     }
44 
45     public void setuService(UserService uService) {
46         this.uService = uService;
47     }
48 
49     public User getUser() {
50         return user;
51     }
52 
53     public void setUser(User user) {
54         this.user = user;
55     }
56 
57     @Override
58     public String execute() throws Exception {
59         /**
60          * 账号密码：wyl,1234
61          */
62         if (uService.login(user)) {
63             ActionContext atx = ActionContext.getContext();
64             Map<String, Object> session = atx.getSession();
65             //对应于 WylInterceptor.java拦截器，这个拦截器里需要用到
66             session.put("currentUser", user);
67             //用来设置登录超时的参数
68             session.put("lastTime", UtilTime.getCurTime());
69             return SUCCESS;
70         } else {
71 //            this.error = "error";
72 //            return this.error;
73             HttpServletResponse  resp = ServletActionContext.getResponse();
74             //不加 resp.setContentType("text/html;charset=UTF-8"); 会出现页面的中文为乱码的情况
75             resp.setContentType("text/html;charset=UTF-8");
76             PrintWriter out  = resp.getWriter();
77             out.println("账号："+user.getUserName()+",<br/>密码："+user.getPassWord()+"  的不正确，请确认");
78 //            out.println("<br/><input type="button" value="点我" />");
79             out.println("<a href="login.jsp" style="color:orange;">点我重新登陆</a>");
80             /**
81              * 下面的Map<String, Object> session = atx.getSession();为了演示获取到的session(实际上是Mapper，Struts2框架做了封装)
82              */
83             ActionContext atx = ActionContext.getContext();
84             Map<String, Object> session = atx.getSession();
85             Set<String> set = session.keySet();
86             Iterator it =  set.iterator();
87             while(it.hasNext()){
88                 String key = (String) it.next();
89                 String val = (String) session.get(key);
90                 System.out.println("key:"+key+",value:"+val);
91             }
92             //什么都不返回，直接用HttpServletResponse在网页上写提示
93             return null;
94         }
95     }
96 }

，调试截图：