Struts2中action获取request、response、session的方式

    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：

/**
    * 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;
    }

}

/** 
	* 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");%>--%>

    <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");%>--%>

不明白为什么JavaEye把“<”解析不出来......