Struts2 access mode decoupled from Servlet API
1. Use the ActionContext class to obtain the Map object corresponding to the Servlet API object
1 Get the Map object corresponding to HttpServletRequest
2 Get the Map object corresponding to HttpSessiont
3 Get the Map object corresponding to ServletContext
2.Struts2 injects the Map object corresponding to the Servlet API object into the Action
Struts and Servlet API coupling access mode
3 Access methods coupled with the Servlet API
后台绑定数据
前台获取数据
Request.setAttribute("The name placed on the server", "object collection");
ServletActionContext.getRequest();//Get the request (response)
1. Bind the value to the server and find the value[LoginAction] through the key value
package com.lanou.entity;
import javax.servlet.http.HttpServletRequest;
import org.apache.struts2.ServletActionContext;
//包名小写 类名大写
public class LoginAction {
public String execute() {
HttpServletRequest request =ServletActionContext.getRequest();
//绑定值request
request.setAttribute("reqkey","reqvalue");
//绑定值session
request.getSession().setAttribute("seskey", "sesvalue");
//绑定值到Context[后台只要上下文]
ServletActionContext.getServletContext().setAttribute("appkey", "appvalue");
return "success";
}
}
2. Get [success.jsp] from the front desk
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<html>
<head>
</head>
<body>
request对象:${request.reqkey}
session对象:${session.seskey}
<!--可以直接写application 因为是就打内置对象之一 -->
application对象:${application.appkey}
</body>
</html>