Struts2中action获取request、response、session的方式

之前用惯struts1.x，那些request啊session之类都是方法自带有的，我们直接调用就可以；而平时公司项目中用到有struts2.x的话，action所继承的BaseAction等底层那些都是人家封装好的，直接继承就可以。现在自己搞个，才知道struts2的request、response、session原来都被隐藏的了，不过struts2提供有两种方式给我们访问。

第一种方式，非IoC(Spring中的控制反转)方式：

/**    
    * File Name：BaseAction.java * Version： * Date：2010-1-27 * Copyright Belongs To Musoon Corporation 2010     
*/   
        
package com.action;    
   
import java.util.Map;    
   
import javax.servlet.http.HttpServletRequest;    
import javax.servlet.http.HttpServletResponse;    
   
import org.apache.struts2.ServletActionContext;    
   
import com.opensymphony.xwork2.ActionContext;    
import com.opensymphony.xwork2.ActionSupport;    
   
/**   
* Project Name：ZhiMing   ** Class Name：BaseAction    
* Author：Musoon        ** Created Time：2010-1-27 下午06:45:35    
* Changed By：Musoon   ** Changed Time：2010-1-27 下午06:45:35    
* Changed Memo：    
* @version    
* Class Description：    
*/   
   
public class BaseAction extends ActionSupport {    
   
    private static final long serialVersionUID = 7620009925942346125L;    
        
    ActionContext context = ActionContext.getContext();    
    HttpServletRequest request = (HttpServletRequest) context.get(ServletActionContext.HTTP_REQUEST);    
    HttpServletResponse response = (HttpServletResponse) context.get(ServletActionContext.HTTP_RESPONSE);    
    Map session = context.getSession();    
    //SessionMap session = (SessionMap) context.get(ActionContext.SESSION);    
        
} 
/** 
* File Name：BaseAction.java * Version： * Date：2010-1-27 * Copyright Belongs To Musoon Corporation 2010 
*/

package com.action;

import java.util.Map;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.struts2.ServletActionContext;

import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionSupport;

/**
* Project Name：ZhiMing   ** Class Name：BaseAction 
* Author：Musoon        ** Created Time：2010-1-27 下午06:45:35 
* Changed By：Musoon   ** Changed Time：2010-1-27 下午06:45:35 
* Changed Memo： 
* @version 
* Class Description： 
*/

public class BaseAction extends ActionSupport {

private static final long serialVersionUID = 7620009925942346125L;

ActionContext context = ActionContext.getContext();
HttpServletRequest request = (HttpServletRequest) context.get(ServletActionContext.HTTP_REQUEST);
HttpServletResponse response = (HttpServletResponse) context.get(ServletActionContext.HTTP_RESPONSE);
Map session = context.getSession();
//SessionMap session = (SessionMap) context.get(ActionContext.SESSION);

}

我们平常所说的session一般是HttpSession，但在struts2中被封装成了Map类型。

第二种方式，IoC方式：

/**    
    * File Name：BaseAction.java * Version： * Date：2010-1-27 * Copyright Belongs To Musoon Corporation 2010     
*/   
        
package com.action;    
   
import java.util.Map;    
   
import javax.servlet.http.HttpServletRequest;    
import javax.servlet.http.HttpServletResponse;    
   
import org.apache.struts2.dispatcher.SessionMap;    
import org.apache.struts2.interceptor.ServletRequestAware;    
import org.apache.struts2.interceptor.ServletResponseAware;    
import org.apache.struts2.interceptor.SessionAware;    
   
import com.opensymphony.xwork2.ActionContext;    
import com.opensymphony.xwork2.ActionSupport;    
   
   
   
/**   
* Project Name：ZhiMing   ** Class Name：BaseAction    
* Author：Musoon        ** Created Time：2010-1-27 下午06:45:35    
* Changed By：Musoon   ** Changed Time：2010-1-27 下午06:45:35    
* Changed Memo：    
* @version    
* Class Description：    
*/   
   
public class BaseAction extends ActionSupport implements SessionAware, ServletRequestAware, ServletResponseAware {    
   
    private static final long serialVersionUID = 7620009925942346125L;    
        
    ActionContext context = ActionContext.getContext();    
    HttpServletRequest request;    
    HttpServletResponse response;    
    SessionMap session;    
        
    //获取request,response,session方式一，非IoC方式，不用实现SessionAware, ServletRequestAware, ServletResponseAware    
    //ActionContext context = ActionContext.getContext();    
    //HttpServletRequest request = (HttpServletRequest) context.get(ServletActionContext.HTTP_REQUEST);    
    //HttpServletResponse response = (HttpServletResponse) context.get(ServletActionContext.HTTP_RESPONSE);    
    //Map session = context.getSession();    
    //SessionMap session = (SessionMap) context.get(ActionContext.SESSION);    
        
    //获取request,response,session方式一，IoC方式，必须实现SessionAware, ServletRequestAware, ServletResponseAware    
    public void setSession(Map map) {    
        this.session = (SessionMap) map;    
    }    
    public void setServletRequest(HttpServletRequest request) {    
        this.request = request;    
    }    
    public void setServletResponse(HttpServletResponse response) {    
        this.response = response;    
    }    
        
} 


     

这样我们在写action时直接继承这个BaseAction，那些request、response、session之类就可以正常地用了，good。等我下午有时间反编译一下别人封装好的BaseAction，看看是不是这样搞的，哈哈。

ps：
平时我们在action中要把值设进session然后在jsp页面去的话，一般是这样(struts2不行)：

public String findAllUsers() throws Exception {    
        
    List<User> userList = userService.findAllUsers();    
        
    HttpSession se = request.getSession();    
    se.setAttribute("userList", userList);    
        
    session.put("userList", userList);    
    //session.put("aaa", "bbb");    
    //session.put(key, value);    
        
    //request.setAttribute("userList", userList);    
        
    return SUCCESS;    
} 
public String findAllUsers() throws Exception {
  
   List<User> userList = userService.findAllUsers();
  
   HttpSession se = request.getSession();
   se.setAttribute("userList", userList);
  
   session.put("userList", userList);
   //session.put("aaa", "bbb");
   //session.put(key, value);
  
   //request.setAttribute("userList", userList);
  
   return SUCCESS;
}

在struts2中，设进session的话则应该变成这样了，因为session是一个map类型：

public String findAllUsers() throws Exception {    
        
    List<User> userList = userService.findAllUsers();    
    session.put("userList", userList);    
    //request.setAttribute("userList", userList);    
        
    return SUCCESS;    
} 
public String findAllUsers() throws Exception {
  
   List<User> userList = userService.findAllUsers();
   session.put("userList", userList);
   //request.setAttribute("userList", userList);
  
   return SUCCESS;
}

据说，如果直接到jsp页面的话，一般推荐用request而不用session，多人单机同时操作的话保险一点，虽然一个浏览器同一时间只有一个session。

在jsp页面取值的话：

<table class="table_report">   
    <tr>     
        <th>用户ID</th>   
        <th>用户名称</th>   
        <th>用户性别</th>   
        <th>用户年龄</th>   
        <th>用户地址</th>   
        <th>用户电话</th>   
        <th>用户邮箱</th>   
    </tr>   
    <!-- struts2最正规的取值方式 -->   
<%-- <s:iterator id="user" value="%{#session.userList}">--%>   
   
   <s:iterator id="user" value="#session.userList">   
<%--   <s:iterator id="user" value="#request.userList">--%>   
    <tr>   
        <td>${user.id}</td>   
        <td>${user.name}</td>   
        <td>${user.sex}</td>   
        <td>${user.age}</td>   
        <td>${user.address}</td>   
        <td>${user.phone}</td>   
        <td>${user.email}</td>   
    </tr>   
    </s:iterator>   
</table>   
<%-- 用完要清空 --%>   
<%request.removeAttribute("userList");%>   
<%--<%session.removeAttribute("userList");%>--%>