Struts2实现显示在线人数-蒲公英云

Struts2实现显示在线人数

墨蓝 2022-04-23 10:30 236阅读 0赞

登录成功以后将用户信息放入Session域中（在线人数+1）

在线人数信息保存在application域中

登出时使session直接失效（在线人数-1）

index

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
  <h3>欢迎登陆</h3>
        <form action="user_login" method="post">
        用户名 <input type="text"name="username"/><br/>
        密码 <input type="password"name="password"/><br/>
        <input type="submit" value="登录"/><br/>
        </form>
</body>
</html>

success

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>登录成功</title>
</head>
<body>
    <h1>欢迎${sessionScope.loginUser}登录！</h1>
    <h3>当前在线人数：${applicationScope.count}</h3>
    <h1><a href="user_logout">登出</a></h1>
</body>
</html>

logout

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
    <h1>欢迎下次再来</h1>
</body>
</html>

Struts.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC
    "-//Apache Software Foundation//DTD Struts Configuration 2.3//EN"
    "http://struts.apache.org/dtds/struts-2.3.dtd">
<struts>
    <constant name="struts.enable.DynamicMethodInvocation" value="false" />
    <constant name="struts.devMode" value="true" />
    <package name="default" namespace="/" extends="struts-default">
        <action name="user_login" class="com.Action.UserAction"
            method="login">
            <result>/WEB-INF/views/success.jsp</result>
        <allowed-methods>*</allowed-methods>
        </action>
        <action name="user_logout" class="com.Action.UserAction"
            method="logout">
            <result>/WEB-INF/views/baby.jsp</result>
        <allowed-methods>*</allowed-methods>
        </action>
    </package>
</struts>

UserAction

package com.Action;
import java.util.Map;
import org.apache.struts2.dispatcher.SessionMap;
import org.apache.struts2.interceptor.ApplicationAware;
import org.apache.struts2.interceptor.SessionAware;
public class UserAction implements SessionAware,ApplicationAware{
    private String username;
    private String password;
    public String getUsername() {
        return username;
    }
    public void setUsername(String username) {
        this.username = username;
    }
    public String getPassword() {
        return password;
    }
    public void setPassword(String password) {
        this.password = password;
    }
public String logout() {
        ((SessionMap)session).invalidate();
            return "success";
    }
    public String login() {
        if (session.get("loginUser") != null) {
            return "success";
        }
        System.out.println(username+password);
        session.put("loginUser",username);
        Integer count = (Integer) application.get("count");
        if (count == null) {
            count = 0;
        }
        application.put("count", count+1);
        return "success";
    }
    private Map<String, Object>session;
    @Override
    public void setSession(Map<String, Object> arg0) {
        this.session = arg0;
    }
    private Map<String, Object>application;
    @Override
    public void setApplication(Map<String, Object> arg0) {
        this.application = arg0;
    }
}