• SpringMVC(十二)自定义异常处理器 HandlerExceptionResolver(接口)


    自定义异常处理器和系统异常处理器的提升版可以实现相同的功能,但是使用的方法不同,自定义异常处理器可以不用在配置文件中配置name多东西,只需要一个异常处理器就可以,有需要的话也可以配置一个视图解析器,但是包扫描器是必须的

    先定义一个类让他实现 HandlerExceptionResolver 接口

    package demo14SelfException;
    
    import org.springframework.web.servlet.HandlerExceptionResolver;
    import org.springframework.web.servlet.ModelAndView;
    
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
    
    /**
     * Created by mycom on 2018/3/30.
     */
    public class MyHandlerExceptionResolver implements HandlerExceptionResolver {
        /**
         * 解析异常
         * @param httpServletRequest
         * @param httpServletResponse
         * @param o
         * @param ex
         * @return
         */
        public ModelAndView resolveException(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, Exception ex) {
            ModelAndView mv=new ModelAndView();
            mv.addObject("ex",ex);//保存的数据,在页面上用EL表达式展示错误信息
            //如果不满足下面两个条件,就走这个默认的页面
            mv.setViewName("error");
            //判断异常类型  是用户名异常就到用户名异常类中是年龄异常就到年龄异常类中
            if(ex instanceof NameException){
                //指定特定的异常页面
                mv.setViewName("nameException");
            }
            if(ex instanceof AgeException){
                mv.setViewName("ageException");
            }
            //最后返回ModelAndView
            return mv;
        }
    }

    在这个类中需要两个异常类NameException和AgeException

    package demo14SelfException;
    
    /**
     * Created by mycom on 2018/3/30.
     */
    public class NameException extends Exception {
        public NameException() {
            super();
        }
    
        public NameException(String message) {
            super(message);
        }
    }
    package demo14SelfException;
    
    /**
     * Created by mycom on 2018/3/30.
     */
    public class AgeException extends Exception {
        public AgeException() {
            super();
        }
    
        public AgeException(String message) {
            super(message);
        }
    }

    在异常控制器中

    package demo14SelfException;
    
    import org.springframework.stereotype.Controller;
    import org.springframework.web.bind.annotation.RequestMapping;
    
    /**
     * Created by mycom on 2018/3/30.
     */
    @Controller
    public class ExceptionController {
    
        @RequestMapping("/first")
        public String doFirst(String name,int age) throws Exception {
            //根据异常的不同返回不同的页面
            if(!name.equals("admin")){
                //如果用户名输入不正确,走姓名异常这个类
                throw new NameException("用户名异常");
            }
            if(age>60){
                throw new AgeException("年龄不符合");
            }
            //最后成功的话就走成功的页面
            return "success";
        }
    }

    配置文件中

    <?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:mvc="http://www.springframework.org/schema/mvc"
           xmlns:context="http://www.springframework.org/schema/context"
           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">
    
        <!--包扫描器-->
        <context:component-scan base-package="demo14SelfException"></context:component-scan>
    
        <!--视图解析器-->
        <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
            <property name="prefix" value="/error/"></property>
            <property name="suffix" value=".jsp"></property>
        </bean>
    
        <!--异常处理器  自己定义的类-->
        <bean class="demo14SelfException.MyHandlerExceptionResolver"></bean>
    
    
    
    </beans>

    需要的页面

    登录页面

    <%--
      Created by IntelliJ IDEA.
      User: mycom
      Date: 2018/3/26
      Time: 11:57
      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>
    <h2>登录</h2>
    <form action="${pageContext.request.contextPath}/first" method="post">
        用户名:<input type="text" name="name" value="${name}"/>
        年龄:<input type="text" name="age" value="${age}"/>
        出生日期:<input type="text" name="birthday"/>
        <input type="submit" value="提交">
    </form>
    </body>
    </html>

    普通错误页面

    <%--
      Created by IntelliJ IDEA.
      User: mycom
      Date: 2018/3/26
      Time: 11:57
      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>
    <h2>出错了!!!!</h2>
    ${ex.message}
    </body>
    </html>

    成功页面

    <%--
      Created by IntelliJ IDEA.
      User: mycom
      Date: 2018/3/26
      Time: 11:57
      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>
      ${username}登录成功!
    </body>
    </html>

    姓名错误

    <%--
      Created by IntelliJ IDEA.
      User: mycom
      Date: 2018/3/30
      Time: 12:35
      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>
    姓名不符合 ${ex.message}
    </body>
    </html>

    年龄错误

    <%--
      Created by IntelliJ IDEA.
      User: mycom
      Date: 2018/3/30
      Time: 12:35
      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>
    年龄不符合 ${ex.message}
    </body>
    </html>
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  • 原文地址:https://www.cnblogs.com/my-123/p/8681132.html
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