目录
注意：
1.此项目中的异常处理器是通过继承BaseController实现的
2.在此项目之前需要有以下基础：
SpringMVC中的拦截器介绍：https://blog.csdn.net/qq_40323256/article/details/89875160
springmvc中的异常处理器：https://blog.csdn.net/qq_40323256/article/details/94122087
一，项目结构
二，.java
User.java
package com.lijiang.bean;
public class User {
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;
}
}
BaseController.java
package com.lijiang.controller;
import javax.servlet.http.HttpServletRequest;
import org.springframework.web.bind.annotation.ExceptionHandler;
import com.lijiang.exception.MyException;
public class BaseController {
@ExceptionHandler(MyException.class)
public String handleException(Exception e,HttpServletRequest request){
request.setAttribute("error", e.getMessage());
return "exception";
}
}
LoginController.java
package com.lijiang.controller;
import javax.servlet.http.HttpSession;
import org.apache.catalina.connector.Request;
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.lijiang.bean.User;
import com.lijiang.exception.MyException;
@Controller
public class LoginController extends BaseController {
@RequestMapping("loginpage.do")
public String toLoginPage(){
return "login";
}
@RequestMapping("user/home.do")
public String toUserHome(){
return "userhome";
}
@RequestMapping(value="doLogin.do",method=RequestMethod.POST)
public String doLogin(User u,HttpSession session){
try {
User user=new User();
user.setUsername("lijiang");
user.setPassword("123");
if(u.getUsername().equals(user.getUsername())&&u.getPassword().equals(user.getPassword())){
session.setAttribute("user", u);
return "userhome";
}
else{
return "login";
}
}
catch (Exception e) {
return "login";
}
}
@RequestMapping("exception.do")
public void exception() throws Exception{
throw new MyException("触发异常测试");
}
}
MyException.java
package com.lijiang.exception;
public class MyException extends Exception {
public MyException (String msg){
super(msg);
}
}
LoginInterceptor.java
package com.lijiang.interceptor;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;
public class LoginInterceptor implements HandlerInterceptor {
@Override
public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler)
throws Exception {
System.out.println("preHandle");
Object user = request.getSession().getAttribute("user");
if(user==null){
response.sendRedirect(request.getContextPath()+"/loginpage.do");
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");
}
}
三，.jsp
exception.jsp
<%@ 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>异常</title>
</head>
<body>
<h1>出现异常！异常信息：${error }</h1>
</body>
</html>login.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>请登录</title>
</head>
<body>
<form action="${pageContext.request.contextPath }/doLogin.do" method="post">
用户名:<input type="text" name="username">
密码:<input type="password" name="password">
<input type="submit" value="登录">
</form>
</body>
</html>userhome.jsp
<%@ 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>用户中心</title>
</head>
<body>
恭喜您，成功登录用户中心！
</body>
</html>index.jsp
<%@ 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>首页</title>
</head>
<body>
<a href="${pageContext.request.contextPath }/loginpage.do">登录</a>
<a href="${pageContext.request.contextPath }/user/home.do">用户中心</a>
<a href="${pageContext.request.contextPath }/exception.do">触发异常</a>
</body>
</html>四，.xml
web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd" id="WebApp_ID" version="3.1">
<display-name>InterceptorAndExceptionProject</display-name>
<welcome-file-list>
<welcome-file>index.html</welcome-file>
<welcome-file>index.htm</welcome-file>
<welcome-file>index.jsp</welcome-file>
<welcome-file>default.html</welcome-file>
<welcome-file>default.htm</welcome-file>
<welcome-file>default.jsp</welcome-file>
</welcome-file-list>
<servlet>
<servlet-name>springmvc</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<!-- 读取springmvc配置文件 -->
<param-name>contextConfigLocation</param-name>
<param-value>classpath:springmvc.xml</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>springmvc</servlet-name>
<!-- 拦截规则 -->
<!-- 1.*.htm,*.do,*.action以扩展名方式拦截，什么情况下都可以使用。但是不拦截静态资源如:.jpg,.css,.js,.png 。 -->
<!-- 2./ 不拦截静态资源如:.jpg,.css,.js,.png -->
<!-- /*全部拦截 包括jsp和所有静态资源。不推荐使用 -->
<!-- <url-pattern>*.sikiedu</url-pattern> -->
<url-pattern>/</url-pattern>
</servlet-mapping>
</web-app>springmvc.xml
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:mvc="http://www.springframework.org/schema/mvc"
xmlns:aop="http://www.springframework.org/schema/aop"
xsi:schemaLocation="http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.3.xsd
http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.3.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.3.xsd
http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.3.xsd">
<!-- 开启注解扫描 -->
<context:component-scan base-package="com.lijiang.*"/>
<!-- 开启注解驱动 -->
<mvc:annotation-driven/>
<!-- 配置视图解析器 -->
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix" value="/WEB-INF/jsp/"/>
<property name="suffix" value=".jsp"/>
</bean>
<!-- 登录验证拦截器 -->
<mvc:interceptors>
<mvc:interceptor>
<mvc:mapping path="/user/**"/>
<bean class="com.lijiang.interceptor.LoginInterceptor"></bean>
</mvc:interceptor>
</mvc:interceptors>
</beans>五，运行结果
右键项目-【run as】-【run on server】
