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Struts2获取request的几种方式汇总

2013-09-23 13:56 253 查看
Struts2获取request三种方法

struts2里面有三种方法可以获取request,最好使用ServletRequestAware接口通过IOC机制注入Request对象。

在Action中获取request方法一:

在Action中的代码:

Map request = (Map)ActionContext.getContext().get("request");

List<Task> tasks = taskManager.findAll();

request.put("tasks", tasks);

在JSP页面中获取其中的值:

<s:iterator id="task" value="#request.tasks">

<tr class="table_header">

<td><s:property value="#task.tname"/></td>

<td><s:property value="#task.tuid"/></td>

<td><s:property value="#task.tstartTime"/></td>

<td><s:property value="#task.tendTime"/></td>

<td><s:property value="#task.tstate"/></td>

<td><input type="radio" id="choose" name="choose" onclick="getId(this.value)" value="<s:property value='#task.tid'/>"/></td>

</tr>

</s:iterator>

--------------------------------------------------------------------------------------------

方法二:通过ServletActionContext类来获取,使用struts2经验如果处理get传参是中文,只能使用该方法进行处理乱码问题

Action中代码:

HttpServletRequest request = ServletActionContext.getRequest();

request.setAttribute("username", "zhangsan");

在jsp中获取其中的值

<s:property value="#request.username">或者${requestScope.req}

--------------------------------------------------------------------------------------------

方法三:通过ServletRequestAware接口通过IOC机制注入Request对象

Action中的代码:

Action实现ServletRequestAware接口,实现接口中的方法

private HttpServletRequest request;

//实现接口中的方法

public void setServletRequest(HttpServletRequest request){

this.request = request;

}

//然后在execute()方法中就可以使用了

public String execute(){

request.setAttribute("username", "zhangsan");

request.getSession().getServletContext().getApplication(); //得到Application

}

该方法必须要实现,而且该方法是自动被调用

这个方法在被调用的过程中,会将创建好的request对象通过参数的方式传递给你,你可以用来赋给你本类中的变量,然后request就可以使用了

注意:setServletRequest()方法一定会再execute()方法被调用前执行

在jsp页面中获取其中的值

<s:property value="#request.task.tname"/>

/本篇文章来源于Java秀,原文出处:http://www.java.sh/article/jsp/1353.html

struts2超链接传值: <s:a href="info.action?id=%{#list.id}"> <s:property value="#list.title"/></s:a>

第一种方式,非IoC(Spring中的控制反转)方式:

Java代码

/**

* 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:

Java代码

/**

* 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):

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");%>--%>
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