体系课

回到首页 个人中心 反馈问题 注册登录
下载APP
首页 课程 实战 体系课 手记 专栏 慕课教程

为什么会报错呢？

来源：4-5 自定义异常类

Zoom0

2020-11-13 16:20:06

安卓光参数名不一样不会报错啊。没明白

（注释的代码是老师敲得）

http://img.mukewang.com/climg/5fae409809a48eeb06881051.jpg


换成自己代码就会报错如下：

http://img.mukewang.com/climg/5fae41a709788cb016510153.jpg​

http://img.mukewang.com/climg/5fae41af0926329106870547.jpg


求老师解释

写回答

8回答

好帮手慕小班

2020-11-14

已采纳

同学你好，同学可以参考如下思路来理解一下：

自定义的异常类继承了RuntimeException类

http://img.mukewang.com/climg/5faf78cb093c49b706060152.jpg

RuntimeException继承了Exception

http://img.mukewang.com/climg/5faf78dc091600d505180307.jpg

Exception继承了Throwable

http://img.mukewang.com/climg/5faf790c09dea8b404880086.jpg

java中Throwable类是所有异常类的父类

http://img.mukewang.com/climg/5faf79c109aeaba605960096.jpg

在Throwable中getMessage方法，是返回此 throwable 的详细消息字符串。

​http://img.mukewang.com/climg/5faf7a5309d7c8b005660187.jpg

所以如果需要返回具体的异常信息需要使用重写后的getMessage方法。

0

好帮手慕小班

2020-11-14

同学你好，根据同学贴出的报错信息，在UserServiceImpl的27行，抛出的ImoocMallException为空

http://img.mukewang.com/climg/5faf4558095f646f07140204.jpg

​http://img.mukewang.com/climg/5faf461a09e2f1e811290373.jpg

如上所示的步骤来尝试一下。

0
hoom0
h 难道说，如果想成为自定义异常类，就必须重写父类的方法？
h020-11-14
共3条回复

Zoom0

提问者

2020-11-13

第二部分

[spring-webmvc-5.2.1.RELEASE.jar:5.2.1.RELEASE]

at javax.servlet.http.HttpServlet.service(HttpServlet.java:660) ~[tomcat-embed-core-9.0.27.jar:9.0.27]

at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883) ~[spring-webmvc-5.2.1.RELEASE.jar:5.2.1.RELEASE]

at javax.servlet.http.HttpServlet.service(HttpServlet.java:741) ~[tomcat-embed-core-9.0.27.jar:9.0.27]

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231) ~[tomcat-embed-core-9.0.27.jar:9.0.27]

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.27.jar:9.0.27]

at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53) ~[tomcat-embed-websocket-9.0.27.jar:9.0.27]

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.27.jar:9.0.27]

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.27.jar:9.0.27]

at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100) ~[spring-web-5.2.1.RELEASE.jar:5.2.1.RELEASE]

at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) ~[spring-web-5.2.1.RELEASE.jar:5.2.1.RELEASE]

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.27.jar:9.0.27]

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.27.jar:9.0.27]

at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93) ~[spring-web-5.2.1.RELEASE.jar:5.2.1.RELEASE]

at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) ~[spring-web-5.2.1.RELEASE.jar:5.2.1.RELEASE]

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.27.jar:9.0.27]

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.27.jar:9.0.27]

at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201) ~[spring-web-5.2.1.RELEASE.jar:5.2.1.RELEASE]

at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) ~[spring-web-5.2.1.RELEASE.jar:5.2.1.RELEASE]

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.27.jar:9.0.27]

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.27.jar:9.0.27]

at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:202) [tomcat-embed-core-9.0.27.jar:9.0.27]

at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) [tomcat-embed-core-9.0.27.jar:9.0.27]

at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:526) [tomcat-embed-core-9.0.27.jar:9.0.27]

at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:139) [tomcat-embed-core-9.0.27.jar:9.0.27]

at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92) [tomcat-embed-core-9.0.27.jar:9.0.27]

at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74) [tomcat-embed-core-9.0.27.jar:9.0.27]

at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343) [tomcat-embed-core-9.0.27.jar:9.0.27]

at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:408) [tomcat-embed-core-9.0.27.jar:9.0.27]

at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) [tomcat-embed-core-9.0.27.jar:9.0.27]

at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:861) [tomcat-embed-core-9.0.27.jar:9.0.27]

at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1579) [tomcat-embed-core-9.0.27.jar:9.0.27]

at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-embed-core-9.0.27.jar:9.0.27]

at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1130) [?:?]

at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:630) [?:?]

at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-embed-core-9.0.27.jar:9.0.27]

at java.lang.Thread.run(Thread.java:832) [?:?]



0

Zoom0

提问者

2020-11-13

console打印的运行信息，因为字数限制，服务启动时候打印的我删了。分开截取 ，以下是posman执行之后出来的信息第一部分


[11:13 20:18:16.172] [ERROR] [org.apache.catalina.core.ContainerBase.[Tomcat].[localhost].[/].[dispatcherServlet]] - Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is com.thawne.mall.exception.ImoocMallException] with root cause

com.thawne.mall.exception.ImoocMallException: null

at com.thawne.mall.service.impl.UserServiceImpl.register(UserServiceImpl.java:27) ~[classes/:?]

at com.thawne.mall.controller.UserController.register(UserController.java:44) ~[classes/:?]

at com.thawne.mall.controller.UserController$$FastClassBySpringCGLIB$$d234471f.invoke(<generated>) ~[classes/:?]

at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:218) ~[spring-core-5.2.1.RELEASE.jar:5.2.1.RELEASE]

at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:769) ~[spring-aop-5.2.1.RELEASE.jar:5.2.1.RELEASE]

at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163) ~[spring-aop-5.2.1.RELEASE.jar:5.2.1.RELEASE]

at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:747) ~[spring-aop-5.2.1.RELEASE.jar:5.2.1.RELEASE]

at org.springframework.aop.framework.adapter.MethodBeforeAdviceInterceptor.invoke(MethodBeforeAdviceInterceptor.java:56) ~[spring-aop-5.2.1.RELEASE.jar:5.2.1.RELEASE]

at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.2.1.RELEASE.jar:5.2.1.RELEASE]

at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:747) ~[spring-aop-5.2.1.RELEASE.jar:5.2.1.RELEASE]

at org.springframework.aop.framework.adapter.AfterReturningAdviceInterceptor.invoke(AfterReturningAdviceInterceptor.java:55) ~[spring-aop-5.2.1.RELEASE.jar:5.2.1.RELEASE]

at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.2.1.RELEASE.jar:5.2.1.RELEASE]

at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:747) ~[spring-aop-5.2.1.RELEASE.jar:5.2.1.RELEASE]

at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:93) ~[spring-aop-5.2.1.RELEASE.jar:5.2.1.RELEASE]

at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.2.1.RELEASE.jar:5.2.1.RELEASE]

at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:747) ~[spring-aop-5.2.1.RELEASE.jar:5.2.1.RELEASE]

at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:689) ~[spring-aop-5.2.1.RELEASE.jar:5.2.1.RELEASE]

at com.thawne.mall.controller.UserController$$EnhancerBySpringCGLIB$$f5dc610d.register(<generated>) ~[classes/:?]

at jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:?]

at jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:64) ~[?:?]

at jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:?]

at java.lang.reflect.Method.invoke(Method.java:564) ~[?:?]

at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:190) ~[spring-web-5.2.1.RELEASE.jar:5.2.1.RELEASE]

at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:138) ~[spring-web-5.2.1.RELEASE.jar:5.2.1.RELEASE]

at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:106) ~[spring-webmvc-5.2.1.RELEASE.jar:5.2.1.RELEASE]

at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:888) ~[spring-webmvc-5.2.1.RELEASE.jar:5.2.1.RELEASE]

at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:793) ~[spring-webmvc-5.2.1.RELEASE.jar:5.2.1.RELEASE]

at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87) ~[spring-webmvc-5.2.1.RELEASE.jar:5.2.1.RELEASE]

at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1040) ~[spring-webmvc-5.2.1.RELEASE.jar:5.2.1.RELEASE]

at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:943) ~[spring-webmvc-5.2.1.RELEASE.jar:5.2.1.RELEASE]

at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006) ~[spring-webmvc-5.2.1.RELEASE.jar:5.2.1.RELEASE]

at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:909) ~

0

Zoom0

提问者

2020-11-13

先上代码层面，字数有限制

controller：

http://img.mukewang.com/climg/5fae77ac09c8e3e225001264.jpg

service：

http://img.mukewang.com/climg/5fae77e609e71bb617901332.jpg

异常类

http://img.mukewang.com/climg/5fae783209226b7213141172.jpg

枚举类

http://img.mukewang.com/climg/5fae784f0941910415221428.jpg

以上是这个错误涉及到所有的业务代码。。老师辛苦了。我是菜的不行了


0

好帮手慕小脸

2020-11-13

同学你好，经测试运行上述同学给出的代码并未出现异常。如下所示：

http://img.mukewang.com/climg/5fae684c092697fd14630765.jpg

同学使用老师的代码不会报错是吗？建议同学将错误信息完整贴出，以及这部分的类代码。便于老师测试运行检查问题

0
hoom0
h 老师，代码和console完整贴出，您有时间看看
h020-11-13
共1条回复

Zoom0

提问者

2020-11-13

老师，我枚举类中就是这样写的

http://img.mukewang.com/climg/5fae59400902752013181368.jpg

idea也有提示，所以不是调错了

0

好帮手慕小脸

2020-11-13

同学你好，如下这里的getMsg()是调用ImoocMallExceptionEnum(异常枚举类)的属性，不是自己该类的属性，建议同学更换为其他名称(例如:课程中的message)再试试。

​http://img.mukewang.com/climg/5fae563d094561f508370154.jpg

0

0 学习 · 16556 问题

查看课程

相似问题

老师为什么会说我CategoryVOList为空呀

回答 1

为什么不加这个注解之后运行会报如图错误呢？

回答 1

用户注册总报系统异常怎么办

回答 1

添加管理员过滤器后，管理员添加已存在的分类时，为什么返回的错误信息格式不对呢？

回答 1

点击mybatis-generator:generate报错

回答 1

打开慕课网App查看更多内容