原文出处：http://howtodoinjava.com/spring/spring-mvc/spring-mvc-simplemappingexceptionresolver-example/
这个例子很简单，主要需求是在进行web开发时，当用户访问时出现异常，直接将异常暴露在前台，一是很不友好，二是异常连的输出会直接暴露后台接口，这是很不安全。所以需要当发生异常时都转到一个默认的jsp页面。在spring mvc中，可以使用simpleMappingExceptionResolver来解决这个问题。
1. 构建MAVEN项目。其项目结构如下：
2. 在Controller中抛出异常，则EmployeeCotroller中的代码如下：
package com.howtodoinjava.demo.controller;
import java.util.Date;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import com.howtodoinjava.demo.exception.AuthException;
@Controller
@RequestMapping("/employee-module")
public class EmployeeController {
@RequestMapping(value="/getAllEmployees", method = RequestMethod.GET)
public String welcome(Model model)
{
// throw new AuthException(new Date(), "Something bad happened dude !! Run Away :-(");
throw new NullPointerException();
}
}
同时，添加自己定义的异常类AuthException，代码如下：
package com.howtodoinjava.demo.exception;
import java.util.Date;
public class AuthException extends RuntimeException {
private static final long serialVersionUID = 1L;
private Date date;
private String message;
public AuthException(Date date, String message) {
super();
this.date = date;
this.message = message;
}
public Date getDate() {
return date;
}
public String getMessage() {
return message;
}
@Override
public String toString() {
return "AuthException [date=" + date + ", message=" + message + "]";
}
}
3. 创建jsp文件，当抛出自定义异常时返回view的页面是authException.jsp，当抛出nullPointException时，返回页面是genericView.jsp。
--- authException.jsp页面的代码为：
<%@ taglib prefix="fmt" uri="http://java.sun.com/jsp/jstl/fmt"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
<html>
<head>
<title>Authentication Exception</title>
</head>
<body>
<h2>Exception occured at: </h2><fmt:formatDate value="${exception.date}" pattern="yyyy-MM-dd" />
<h2>Exception Message : </h2>${exception.message}
</body>
</html>
---genericView.jsp
<%@ taglib prefix="fmt" uri="http://java.sun.com/jsp/jstl/fmt"%>
<html>
<head>
<title>Generic Exception</title>
</head>
<body>
<h2>Some generic error message</h2>
</body>
</html>
4. 修改配置文件，在spring-serlvet.xml中增加SimpleMappingExceptionResolver的Bean，具体代码如下：
<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"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.0.xsd">
<context:component-scan base-package="com.howtodoinjava.demo" />
<bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter" />
<bean class="org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping" />
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix" value="/WEB-INF/views/" />
<property name="suffix" value=".jsp" />
</bean>
<bean id="messageSource" class="org.springframework.context.support.ResourceBundleMessageSource">
<property name="basename" value="messages" />
</bean>
<bean class="org.springframework.web.servlet.handler.SimpleMappingExceptionResolver">
<property name="exceptionMappings">
<props>
<prop key="com.howtodoinjava.demo.exception.AuthException">
error/authExceptionView
</prop>
</props>
</property>
<property name="defaultErrorView" value="error/genericView"/>
</bean>
</beans>
5. web.xml以及pom.xml文件分别为：
---web.xml
<web-app id="WebApp_ID" version="2.4"
xmlns="http://java.sun.com/xml/ns/j2ee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee
http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">
<display-name>Spring Web MVC Hello World Application</display-name>
<servlet>
<servlet-name>spring</servlet-name>
<servlet-class>
org.springframework.web.servlet.DispatcherServlet
</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>spring</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
</web-app>
---pom.xml
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.howtodoinjava.mvc</groupId>
<artifactId>exceptionHandlerDemo</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>war</packaging>
<dependencies>
<dependency>
<groupId>javax.validation</groupId>
<artifactId>validation-api</artifactId>
<version>1.0.0.GA</version>
</dependency>
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-validator</artifactId>
<version>4.3.1.Final</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.12</version>
<scope>test</scope>
</dependency>
<!-- Spring MVC support -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>4.1.4.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-web</artifactId>
<version>4.1.4.RELEASE</version>
</dependency>
<!-- Tag libs support for view layer -->
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>jstl</artifactId>
<version>1.2</version>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>taglibs</groupId>
<artifactId>standard</artifactId>
<version>1.1.2</version>
<scope>runtime</scope>
</dependency>
</dependencies>
</project>
执行结果：
输入url: localhost:8080/exceptionHandlerDemo/employee-module/getAllEmployees
--当抛出AuthException异常时，访问得到页面如下所示：
