SpringMVC--统一异常处理的3种方式(附带实例)

mac2025-12-03  7

Spring MVC统一异常处理的3种方式

在 Spring MVC 应用的开发中,不管是对底层数据库操作,还是业务层或控制层操作,都会不可避免地遇到各种可预知的、不可预知的异常需要处理。

如果每个过程都单独处理异常,那么系统的代码耦合度高,工作量大且不好统一,以后维护的工作量也很大。

如果能将所有类型的异常处理从各层中解耦出来,这样既保证了相关处理过程的功能单一,又实现了异常信息的统一处理和维护。

幸运的是,Spring MVC 框架支持这样的实现。Spring MVC 统一异常处理有以下 3 种方式:

使用 Spring MVC 提供的简单异常处理器 SimpleMappingExceptionResolver。实现 Spring 的异常处理接口 HandlerExceptionResolver 自定义自己的异常处理器。使用 @ExceptionHandler 注解实现异常处理

示例

1)创建工程并导入JAR包 2)创建自定义异常类

package pers.zhang.exception; public class MyException extends Exception { private static final long serialVersionUID = 1L; public MyException() { super(); } public MyException(String message) { super(message); } }

3)创建 Dao 层 创建 TestExceptionDao 类,在该类中定义 3 个方法,分别抛出“数据库异常”“自定义异常”和“未知异常”。具体代码如下:

package pers.zhang.dao; import java.sql.SQLException; import org.springframework.stereotype.Repository; @Repository("TestExceptionDao") public class TestExceptionDao { public void daodb() throws Exception { throw new SQLException("Dao中数据库异常"); } public void daomy() throws Exception { throw new SQLException("Dao中自定义异常"); } public void daono() throws Exception { throw new SQLException("Dao中未知异常"); } }

4)创建 Service 层 创建 TestExceptionService 接口和 TestExceptionServiceImpl 实现类,在该接口中定义 6 个方法,其中有 3 个方法调用 Dao 层中的方法,有 3 个是 Service 层的方法。

Service 层的方法是为演示 Service 层的“数据库异常”“自定义异常”和“未知异常”而定义的。

TestExceptionService 接口的代码如下:

package pers.zhang.service; public interface TestExceptionService { public void servicemy() throws Exception; public void servicedb() throws Exception; public void daomy() throws Exception; public void daodb() throws Exception; public void serviceno() throws Exception; public void daono() throws Exception; } package pers.zhang.service; import java.sql.SQLException; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Service; import pers.zhang.dao.TestExceptionDao; import pers.zhang.exception.MyException; @Service("testExceptionService") public class TestExceptionServiceImpl implements TestExceptionService { @Autowired private TestExceptionDao testExceptionDao; @Override public void servicemy() throws Exception { throw new MyException("Service中自定义异常"); } @Override public void servicedb() throws Exception { throw new SQLException("Service中数据库异常"); } @Override public void daomy() throws Exception { testExceptionDao.daomy(); } @Override public void daodb() throws Exception { testExceptionDao.daodb(); } @Override public void serviceno() throws Exception { throw new SQLException("Service中未知异常"); } @Override public void daono() throws Exception { testExceptionDao.daono(); } }

5)创建控制器类

package pers.zhang.controller; import java.sql.SQLException; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Controller; import org.springframework.web.bind.annotation.RequestMapping; import pers.zhang.exception.MyException; import pers.zhang.service.TestExceptionService; @Controller public class TestExceptionController { @Autowired private TestExceptionService testExceptionService; @RequestMapping("/db") public void db() throws Exception { throw new SQLException("控制器中数据库异常"); } @RequestMapping("/my") public void my() throws Exception { throw new MyException("控制器中自定义异常"); } @RequestMapping("/no") public void no() throws Exception { throw new Exception("控制器中未知异常"); } @RequestMapping("/servicedb") public void servicedb() throws Exception { testExceptionService.servicedb(); } @RequestMapping("/servicemy") public void servicemy() throws Exception { testExceptionService.servicemy(); } @RequestMapping("/serviceno") public void serviceno() throws Exception { testExceptionService.serviceno(); } @RequestMapping("/daodb") public void daodb() throws Exception { testExceptionService.daodb(); } @RequestMapping("/daomy") public void daomy() throws Exception { testExceptionService.daomy(); } @RequestMapping("/daono") public void daono() throws Exception { testExceptionService.daono(); } }

6)创建 View 层 测试应用首页面 index.jsp 的代码如下:

<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <%@taglib prefix="spring" uri="http://www.springframework.org/tags"%> <!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>Insert title here</title> </head> <body> <h1>所有的演示例子</h1> <h3><a href="${pageContext.request.contextPath }/daodb"> 处理dao中数据库异常</a></h3> <h3><a href="${pageContext.request.contextPath }/daomy"> 处理dao中自定义异常</a></h3> <h3><a href="${pageContext.request.contextPath }/daono"> 处理dao未知错误 </a></h3> <hr> <h3><a href="${pageContext.request.contextPath }/servicedb">处理 service中数据库异常</a></h3> <h3><a href="${pageContext.request.contextPath }/servicemy">处理 service中自定义异常</a></h3> <h3><a href="${pageContext.request.contextPath }/serviceno">处理 service未知错误</a></h3> <hr> <h3><a href="${pageContext.request.contextPath }/db">处理 controller中数据库异常</a></h3> <h3><a href="${pageContext.request.contextPath }/my">处理 controller中自定义异常</a></h3> <h3><a href="${pageContext.request.contextPath }/no">处理 controller未知错误</a></h3> <hr> <!-- 在 web.xml中配置404 --> <h3> <a href="${pageContext.request.contextPath }/404">404 错误</a> </h3> </body> </html>

404 错误对应页面 404.jsp 的代码如下:

<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <%@taglib prefix="spring" uri="http://www.springframework.org/tags"%> <!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>Insert title here</title> </head> <body> 资源已不在。 </body> </html>

未知异常对应页面 error.jsp 的代码如下:

<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8" isErrorPage="true"%> <%@taglib prefix="spring" uri="http://www.springframework.org/tags"%> <!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>Insert title here</title> </head> <body> <H1>未知错误:</H1><%=exception %> <H2>错误内容:</H2> <% exception.printStackTrace(response.getWriter()); %> </body> </html>

自定义异常对应页面 my-error.jsp 的代码如下:

<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8" isErrorPage="true"%> <%@taglib prefix="spring" uri="http://www.springframework.org/tags"%> <!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>Insert title here</title> </head> <body> <H1>自定义异常错误:</H1><%=exception %> <H2>错误内容:</H2> <% exception.printStackTrace(response.getWriter()); %> </body> </html>

SQL 异常对应页面 sql-error.jsp 的代码如下:

<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8" isErrorPage="true"%> <%@taglib prefix="spring" uri="http://www.springframework.org/tags"%> <!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>Insert title here</title> </head> <body> <H1>数据库异常错误:</H1><%=exception %> <H2>错误内容:</H2> <% exception.printStackTrace(response.getWriter()); %> </body> </html>

7)web.xml

<?xml version="1.0" encoding="UTF-8"?> <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" id="WebApp_ID" version="2.5"> <display-name>SpringMVCErrorDemo</display-name> <!--避免中文乱码--> <filter> <filter-name>encodingFilter</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> <init-param> <param-name>forceEncoding</param-name> <param-value>true</param-value> </init-param> </filter> <filter-mapping> <filter-name>encodingFilter</filter-name> <url-pattern>/*</url-pattern> </filter-mapping> <error-page> <error-code>404</error-code> <location>/WEB-INF/jsp/404.jsp</location> </error-page> <servlet> <servlet-name>springmvc</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <!-- 默认找 /WEB-INF/[servlet的名称]-servlet.xml --> <init-param> <param-name>contextConfigLocation</param-name> <param-value>classpath:springmvc-servlet.xml</param-value> </init-param> </servlet> <servlet-mapping> <servlet-name>springmvc</servlet-name> <url-pattern>/</url-pattern> </servlet-mapping> </web-app>

第一种方式:使用SimpleMappingExceptionResolver类异常处理

使用 org.springframework.web.servlet.handler.SimpleMappingExceptionResolver 类统一处理异常时需要在配置文件中提前配置异常类和 View 的对应关系。配置文件 springmvc-servlet.xml 的具体代码如下:

<?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" xsi:schemaLocation=" http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring一beans.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd"> <!-- 使用扫描机制扫描包 --> <context:component-scan base-package="controller" /> <context:component-scan base-package="service" /> <context:component-scan base-package="dao" /> <!-- 配置视图解析器 --> <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver" id="internalResourceViewResolver"> <!--前缀 --> <property name="prefix" value="/WEB-INF/jsp/" /> <!-- 后缀 --> <property name="suffix" value=".jsp" /> </bean> <!--SimpleMappingExceptionResolver(异常类与 View 的对应关系) --> <bean class="org.springframework.web.servlet.handler.SimpleMappingExceptionResolver"> <!-- 定义默认的异常处理页面,当该异常类型注册时使用 --> <property name="defaultErrorView" value="error"></property> <!-- 定义异常处理页面用来获取异常信息的变量名,默认名为exception --> <property name="exceptionAttribute" value="ex"></property> <!-- 定义需要特殊处理的异常,用类名或完全路径名作为key,异常页名作为值 --> <property name="exceptionMappings"> <props> <prop key="exception.MyException">my-error</prop> <prop key="java.sql.SQLException">sql-error</prop> <!-- 在这里还可以继续扩展对不同异常类型的处理 --> </props> </property> </bean> </beans>

第二种方式:使用HandlerExceptionResolver接口异常处理

org.springframework.web.servlet.HandlerExceptionResolver 接口用于解析请求处理过程中所产生的异常。开发者可以开发该接口的实现类进行 Spring MVC 应用的异常统一处理。

在 springMVCDemo10 应用的 exception 包中创建一个 HandlerExceptionResolver 接口的实现类 MyExceptionHandler,具体代码如下:

package pers.zhang.exception; import java.sql.SQLException; import java.util.HashMap; import java.util.Map; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.springframework.web.servlet.HandlerExceptionResolver; import org.springframework.web.servlet.ModelAndView; public class MyExceptionHandler implements HandlerExceptionResolver { @Override public ModelAndView resolveException(HttpServletRequest arg0, HttpServletResponse arg1, Object arg2, Exception arg3) { Map<String, Object> model = new HashMap<String, Object>(); model.put("ex", arg3); // 根据不同错误转向不同页面(统一处理),即异常与View的对应关系 if (arg3 instanceof MyException) { return new ModelAndView("my-error", model); } else if (arg3 instanceof SQLException) { return new ModelAndView("sql-error", model); } else { return new ModelAndView("error", model); } } }

在实现 HandlerExceptionResolver 接口统一处理异常时将配置文件的代码修改如下:

<?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:p="http://www.springframework.org/schema/p" 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-4.0.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd"> <!-- 扫描@Controler @Service --> <context:component-scan base-package="pers.zhang"/> <!-- 注解驱动 --> <mvc:annotation-driven/> <mvc:resources location="/WEB-INF/jsp/" mapping="/jsp/**"/> <!-- 视图解释器 --> <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"> <property name="prefix" value="/WEB-INF/jsp/"/> <property name="suffix" value=".jsp"/> </bean> <!--托管MyExceptionHandler--> <bean class="pers.zhang.exception.MyExceptionHandler"/> </beans>

第三种方式:使用@ExceptionHandler注解异常处理

创建 BaseController 类,并在该类中使用 @ExceptionHandler 注解声明异常处理方法,具体代码如下:

package pers.zhang.controller; import java.sql.SQLException; import javax.servlet.http.HttpServletRequest; import org.springframework.web.bind.annotation.ExceptionHandler; import pers.zhang.exception.MyException; public class BaseController { /** 基于@ExceptionHandler异常处理 */ @ExceptionHandler public String exception(HttpServletRequest request, Exception ex) { request.setAttribute("ex", ex); // 根据不同错误转向不同页面,即异常与view的对应关系 if (ex instanceof SQLException) { return "sql-error"; } else if (ex instanceof MyException) { return "my-error"; } else { return "error"; } } }

将所有需要异常处理的 Controller 都继承 BaseController 类,示例代码如下:

@Controller public class TestExceptionController extends BaseController{ ... }

在使用 @ExceptionHandler 注解声明统一处理异常时不需要配置任何信息,此时将配置文件的代码修改如下:

<?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:p="http://www.springframework.org/schema/p" 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-4.0.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd"> <!-- 扫描@Controler @Service --> <context:component-scan base-package="pers.zhang"/> <!-- 注解驱动 --> <mvc:annotation-driven/> <mvc:resources location="/WEB-INF/jsp/" mapping="/jsp/**"/> <!-- 视图解释器 --> <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"> <property name="prefix" value="/WEB-INF/jsp/"/> <property name="suffix" value=".jsp"/> </bean> <!--托管MyExceptionHandler--> <!-- <bean class="pers.zhang.exception.MyExceptionHandler"/> --> </beans>

测试

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