SpringMVC拦截器——实现登录验证拦截器的示例代码
程序员文章站
2024-03-05 22:52:01
本例实现登陆时的验证拦截，采用springmvc拦截器来实现
当用户点击到网站主页时要进行拦截，用户登录了才能进入网站主页，否则进入登陆页面
核心代码
首先是in...
本例实现登陆时的验证拦截，采用springmvc拦截器来实现
当用户点击到网站主页时要进行拦截，用户登录了才能进入网站主页，否则进入登陆页面
核心代码
首先是index.jsp,显示链接
<%@ page language="java" import="java.util.*" pageencoding="utf-8"%>
<%
string path = request.getcontextpath();
string basepath = request.getscheme()+"://"+request.getservername()+":"+request.getserverport()+path+"/";
%>
<!doctype html public "-//w3c//dtd html 4.01 transitional//en">
<html>
<head>
<base href="<%=basepath%>" rel="external nofollow" >
<title>首页</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="this is my page">
<!--
<link rel="stylesheet" type="text/css" href="styles.css" rel="external nofollow" >
-->
</head>
<body>
<div style="margin:0 auto;padding-top:100px;font-size:18px;" align="center">
<p><a href="loginpage.html" rel="external nofollow" >登陆</a></p>
<p><a href="user/home.html" rel="external nofollow" >用户中心</a></p>
<p><a href="exception.html" rel="external nofollow" >触发异常</a></p>
</div>
</body>
</html>
controller类
package com.jikexueyuan.demo.springmvc.lesson4.controller;
import javax.annotation.resource;
import javax.servlet.http.httpservletrequest;
import org.springframework.stereotype.controller;
import org.springframework.web.bind.annotation.requestmapping;
import org.springframework.web.bind.annotation.requestmethod;
import org.springframework.web.bind.annotation.requestparam;
import com.jikexueyuan.demo.springmvc.lesson4.constant.global;
import com.jikexueyuan.demo.springmvc.lesson4.exception.myexception;
import com.jikexueyuan.demo.springmvc.lesson4.model.user;
import com.jikexueyuan.demo.springmvc.lesson4.service.loginservice;
/**
* 这个例子讲解了如何定义mvc三层注解，使用@resource进行注入，以及使用@requestmapping、@requestparam 、@sessionattributes
*/
@controller
public class logincontroller extends basecontroller {
@resource
loginservice service;
@resource
httpservletrequest request;
@requestmapping("/exception")
public void exception() throws myexception{
throw new myexception("测试springmvc中的异常捕获");
}
@requestmapping("/loginpage")
public string tologinpage(){
return "/web-inf/jsp/login.jsp";
}
@requestmapping("/user/home")
public string touserhome(){
return "/web-inf/jsp/userhome.jsp";
}
@requestmapping("/logout")
public string logout(){
request.getsession().removeattribute(global.user_session_key);
return "redirect:/";
}
@requestmapping(value = "/dologin", method = requestmethod.post)
public string dologin(@requestparam string username, @requestparam string password){
try {
user user = service.dologin(username, password);
request.getsession().setattribute(global.user_session_key, user);
return "redirect:/user/home.html";
} catch (exception e) {
return "/web-inf/jsp/login.jsp";
}
}
}
当点击用户中心时，触发拦截，相关配置如下
在spring-mvc.xml中加上拦截配置，拦截所有url中包含/user/的请求，当然请求用户中心时就会触发这个拦截器了
<mvc:interceptors>
<mvc:interceptor>
<!-- 拦截所有url中包含/user/的请求 -->
<mvc:mapping path="/user/**"/>
<bean class="com.jikexueyuan.demo.springmvc.lesson4.interceptor.logininterceptor"></bean>
</mvc:interceptor>
</mvc:interceptors>
然后是bean指向的具体的interceptor类，如果session保存的用户信息为null，则跳到login页面，posthandle和aftercompletion方法都不执行，反之都执行。
package com.jikexueyuan.demo.springmvc.lesson4.interceptor;
import javax.servlet.http.httpservletrequest;
import javax.servlet.http.httpservletresponse;
import org.springframework.web.servlet.handlerinterceptor;
import org.springframework.web.servlet.modelandview;
import com.jikexueyuan.demo.springmvc.lesson4.constant.global;
public class logininterceptor implements handlerinterceptor {
@override
public boolean prehandle(httpservletrequest request, httpservletresponse response, object handler) throws exception {
object user = request.getsession().getattribute(global.user_session_key);
if (user == null) {
system.out.println("尚未登录，调到登录页面");
response.sendredirect("/loginpage.html");
return false;
}
return true;
}
@override
public void posthandle(httpservletrequest request, httpservletresponse response, object handler, modelandview modelandview) throws exception {
system.out.println("posthandle");
}
@override
public void aftercompletion(httpservletrequest request, httpservletresponse response, object handler, exception ex) throws exception {
system.out.println("aftercompletion");
}
}
至此，简单的springmvc拦截器就完成了。
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。