struts2中获取request，session，response三大属性

   Struts2中action获取request、response、session的方式2010-07-03 09:53不做不知道，一做才知道自己原来不知道。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：

Java代码
  
    
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;   
  

  
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);   
       
}


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;




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：

Java代码
  

       
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;   
  
  
  
  
  
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;   
    }   
       
}
/**
* 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)：

Java代码
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：

Java代码
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：

Html代码
    <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");%>--%>