自定义异常类

SysException.java

package com.zjw.exception;

import lombok.AllArgsConstructor;
import lombok.Getter;
import lombok.Setter;

/**
 * 自定义异常类
 */
@Getter
@Setter
@AllArgsConstructor
public class SysException extends Exception {

    /**
     * 存储提示信息
     */
    private String message ;

}

异常处理器

实现HandlerExceptionResolver接口。

SysExceptionResolver.java

package com.zjw.exception;

import org.springframework.web.servlet.HandlerExceptionResolver;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * 异常处理器
 */
public class SysExceptionResolver implements HandlerExceptionResolver {

    /**
     * 处理异常业务逻辑
     * @param request
     * @param response
     * @param handler
     * @param ex
     * @return
     */
    @Override
    public ModelAndView resolveException(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) {
        //获取到异常对象
        SysException e = null;
        if (ex instanceof SysException){
            e = (SysException) ex;
        }else {
            e = new SysException("系统正在维护中");
        }
        ModelAndView mv = new ModelAndView();
        mv.addObject("errorMsg",e.getMessage());
        mv.setViewName("error");
        return mv;
    }
}

Controller

package com.zjw.controller;

import com.zjw.exception.SysException;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;

@Controller
@RequestMapping("/user")
public class UserController {

    @RequestMapping("/testException")
    public String testException() throws SysException {
        System.out.println("testException方法执行了。。。。");
        try {
            int a = 1/0 ;
        } catch (Exception e) {
            e.printStackTrace();
            throw new SysException("查询所有用户出现错误了。。。");
        }
        return "success";
    }
}

springmvc.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:mvc="http://www.springframework.org/schema/mvc"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="
            http://www.springframework.org/schema/beans
            http://www.springframework.org/schema/beans/spring-beans.xsd
            http://www.springframework.org/schema/mvc
            http://www.springframework.org/schema/mvc/spring-mvc.xsd
            http://www.springframework.org/schema/context
            http://www.springframework.org/schema/context/spring-context.xsd">

    <!--开启注解扫描-->
    <context:component-scan base-package="com.zjw"/>

    <!--配置视图解析器-->
    <bean id="internalResourceViewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/WEB-INF/pages/"/>
        <property name="suffix" value=".jsp"/>
    </bean>

    <!--前端控制器，哪些静态资源不拦截-->
    <mvc:resources location="/css/" mapping="/css/**"/>
    <mvc:resources location="/images/" mapping="/images/**"/>
    <mvc:resources location="/js/" mapping="/js/**"/>

    <!--配置异常处理器-->
    <bean id="sysExceptionResolver" class="com.zjw.exception.SysExceptionResolver"/>

    <!--开启SpringMVC框架注解的支持-->
    <mvc:annotation-driven/>
</beans>

web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="https://jakarta.ee/xml/ns/jakartaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="https://jakarta.ee/xml/ns/jakartaee https://jakarta.ee/xml/ns/jakartaee/web-app_5_0.xsd"
         version="5.0">
  <display-name>Archetype Created Web Application</display-name>

  <!--配置过滤器-->
  <filter>
    <filter-name>characterEncodingFilter</filter-name>
    <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
    <init-param>
      <param-name>encoding</param-name>
      <param-value>UTF-8</param-value>
    </init-param>
  </filter>
  <filter-mapping>
    <filter-name>characterEncodingFilter</filter-name>
    <url-pattern>/*</url-pattern>
  </filter-mapping>

  <!--配置前端控制器-->
  <servlet>
    <servlet-name>dispatcherServlet</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <init-param>
      <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>dispatcherServlet</servlet-name>
    <url-pattern>/</url-pattern>
  </servlet-mapping>
</web-app>

error.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" isELIgnored="false" %>
<html>
<head>
    <title>error</title>
</head>
<body>
    ${errorMsg}
</body>
</html>