springmvc全局异常处理

深藏阁楼爱情的钟 2024-03-26 11:13 73阅读 0赞

#### 文章目录 ####

*  前言
 *  1、导入依赖
 *  2、配置springmvc.xml文件
 *  3、配置web.xml文件
 *  4、编写异常处理组件
 *  5、编写测试controller
 *  6、准备异常处理页面
 *  7、测试

--------------------

## 前言 ##

在基于Servlet-JSP技术开发的项目中，异常的显示是和前后端分离项目不同的。项目业务层所报出的异常会影响浏览器的页面展示，出现404，500，等常见的浏览器提供的报错页面。这样的话十分影响用户体验。springmvc支持自定义全局异常处理，可以自定义异常处理页面，增强用户体验。

--------------------

## 1、导入依赖 ##

<dependency>
          <groupId>junit</groupId>
          <artifactId>junit</artifactId>
          <version>4.11</version>
          <scope>test</scope>
        </dependency>
        <dependency>
          <groupId>org.springframework</groupId>
          <artifactId>spring-webmvc</artifactId>
          <version>5.3.24</version>
        </dependency>
    
        <dependency>
          <groupId>javax.servlet</groupId>
          <artifactId>javax.servlet-api</artifactId>
          <version>4.0.1</version>
        </dependency>
    
        <dependency>
          <groupId>org.projectlombok</groupId>
          <artifactId>lombok</artifactId>
          <version>1.18.24</version>
        </dependency>
        <dependency>
          <groupId>com.fasterxml.jackson.core</groupId>
          <artifactId>jackson-databind</artifactId>
          <version>2.13.3</version>
        </dependency>
        <dependency>
          <groupId>jstl</groupId>
          <artifactId>jstl</artifactId>
          <version>1.2</version>
        </dependency>

## 2、配置springmvc.xml文件 ##

<?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"
           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"> 
    
        
        <mvc:annotation-driven/>
    
        
        <mvc:default-servlet-handler/>
    
        
        <context:component-scan base-package="com.wmj"/>
    
        
                <bean id="viewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
                        
                        <property name="prefix" value="/WEB-INF/jsp"></property>
                        
                        <property name="suffix" value=".jsp"></property>
                </bean>
    
    </beans>

## 3、配置web.xml文件 ##

<!DOCTYPE web-app PUBLIC
     "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
     "http://java.sun.com/dtd/web-app_2_3.dtd" >
    
    <web-app>
      <display-name>Archetype Created Web Application</display-name>
      
      <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>
      </servlet>
    
      <servlet-mapping>
        <servlet-name>dispatcherServlet</servlet-name>
        <url-pattern>/</url-pattern>
      </servlet-mapping>
    </web-app>

## 4、编写异常处理组件 ##

package com.wmj.handler;
    
    import org.springframework.context.annotation.Configuration;
    import org.springframework.web.servlet.HandlerExceptionResolver;
    import org.springframework.web.servlet.ModelAndView;
    
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
    
    /**
     * --效率，是成功的核心关键--
     *
     * @Author lzl
     * @Date 2023/2/16 09:46
     */
    @Configuration
    public class MyExceptionHandler implements HandlerExceptionResolver {
        
        @Override
        public ModelAndView resolveException(HttpServletRequest request,
                                             HttpServletResponse response,
                                             Object handler,
                                             Exception ex) {
        
            System.out.println("执行异常处理类");
            ModelAndView view = new ModelAndView();
            if(ex instanceof NullPointerException){
        
                view.addObject("msg","空指针异常");
            }else if(ex instanceof ArrayIndexOutOfBoundsException){
        
                view.addObject("msg","数组下标越界异常");
            }else if(ex instanceof ArithmeticException){
        
                view.addObject("msg","算数异常");
            }else{
        
                view.addObject("msg",ex.getMessage());
            }
            view.setViewName("/error");
            return view;
        }
    }

## 5、编写测试controller ##

package com.wmj.controller;
    
    import org.springframework.stereotype.Controller;
    import org.springframework.web.bind.annotation.RequestMapping;
    
    
    /**
     * --效率，是成功的核心关键--
     *
     * @Author lzl
     * @Date 2023/2/16 09:59
     */
    @Controller
    @RequestMapping("/exception")
    public class ExceptionController {
        
        @RequestMapping("/test")
        public String testException(){
        
            int[] arr = new int[3];
            arr[0] = 1;
            arr[1] = 1;
            arr[2] = 1;
            arr[3] = 2;
            //此时下标越界
            return "success";
        }
    }

## 6、准备异常处理页面 ##

默认访问首页跳转测试controller

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
    <html>
    <body>
    <h2>Hello World!</h2>
    <a href="http://localhost:8080/exception/test">点一下跳转</a>
    </body>
    </html>

异常处理页打印信息

<%--
      Created by IntelliJ IDEA.
      User: 我是谁
      Date: 2023/2/16
      Time: 09:56
      To change this template use File | Settings | File Templates.
    --%>
    <%@ page contentType="text/html;charset=UTF-8" language="java" isELIgnored="false" %>
    <html>
    <head>
        <title>Title</title>
    </head>
    <body>
    ${msg}
    </body>
    </html>

## 7、测试 ##

![在这里插入图片描述][16e72073c3ef4d4ab76949bf373151cd.png]  
成功

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[16e72073c3ef4d4ab76949bf373151cd.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/03/26/1575f783b9e54ccd94c03b12cb5b8d77.png