面试见过的异常

总述：checked/unchecked 异常有什么区别？

1️⃣checked：一般是指程序不能直接控制的外界情况，是指在编译的时候就需要检查的一类exception，用户程序中必须采用try catch机制处理或者通过throws交由调用者来处理。这类异常，主要指除了Error以及RuntimeException及其子类之外的异常。
2️⃣unchecked：是指那些不需要在编译的时候就要处理的一类异常。在java体系里，所有的Error以及RuntimeException及其子类都是unchecked异常。再形象直白的理解为不需要try catch等机制处理的异常，可以认为是unchecked的异常。

一、java.lang.IllegalArgumentException: Path cannot be null

2019-06-20 09:49:11,120 [main-EventThread] ERROR [org.apache.curator.framework.imps.CuratorframeworkImpl:566] - Watcher exception
java.lang.IllegalArgumentException: Path cannot be null
        at org.apache.curator.utils.PathUtils.validatePath(PathUtils.java:48)
        at org.apache.curator.utils.PathUtils.validatePath(PathUtils.java:37)
        at org.apache.curator.utils.ZKPaths.fixForNamespace(ZKPaths.java:105)
        at org.apache.curator.framework.imps.NamespaceImpl.fixForNamespace(NamespaceImpl.java:104)
        at org.apache.curator.framework.imps.CuratorframeworkImpl.fixForNamespace(CuratorframeworkImpl.java:594)
        at org.apache.curator.framework.imps.GetChildrenBuilderImpl.forPath(GetChildrenBuilderImpl.java:198)
        at org.apache.curator.framework.imps.GetChildrenBuilderImpl.forPath(GetChildrenBuilderImpl.java:40)
        at com.alibaba.dubbo.remoting.zookeeper.curator.CuratorZookeeperClient$CuratorWatcherImpl.process(CuratorZookeeperClient.java:131)
        at org.apache.curator.framework.imps.NamespaceWatcher.process(NamespaceWatcher.java:68)
        at org.apache.zookeeper.ClientCnxn$EventThread.processEvent(ClientCnxn.java:530)
        at org.apache.zookeeper.ClientCnxn$EventThread.run(ClientCnxn.java:505)

二、Exception in thread “main” com.aliyuncs.exceptions.ClientException:

"C:Program FilesJavajdk1.8.0_161binjava.exe" "-javaagent:D:Program FilesJetBrainsIntelliJ IDEA 2018.3.5libidea_rt.jar=58742:D:Program FilesJetBrainsIntelliJ IDEA 2018.3.5bin" -Dfile.encoding=GBK -classpath "C:Program FilesJavajdk1.8.0_161jrelibcharsets.jar;C:Program FilesJavajdk1.8.0_161jrelibdeploy.jar;C:Program FilesJavajdk1.8.0_161jrelibextaccess-bridge-64.jar;C:Program FilesJavajdk1.8.0_161jrelibextcldrdata.jar;C:Program FilesJavajdk1.8.0_161jrelibextdnsns.jar;C:Program FilesJavajdk1.8.0_161jrelibextjaccess.jar;C:Program FilesJavajdk1.8.0_161jrelibextjfxrt.jar;C:Program FilesJavajdk1.8.0_161jrelibextlocaledata.jar;C:Program FilesJavajdk1.8.0_161jrelibextnashorn.jar;C:Program FilesJavajdk1.8.0_161jrelibextsunec.jar;C:Program FilesJavajdk1.8.0_161jrelibextsunjce_provider.jar;C:Program FilesJavajdk1.8.0_161jrelibextsunmscapi.jar;C:Program FilesJavajdk1.8.0_161jrelibextsunpkcs11.jar;C:Program FilesJavajdk1.8.0_161jrelibextzipfs.jar;C:Program FilesJavajdk1.8.0_161jrelibjavaws.jar;C:Program FilesJavajdk1.8.0_161jrelibjce.jar;C:Program FilesJavajdk1.8.0_161jrelibjfr.jar;C:Program FilesJavajdk1.8.0_161jrelibjfxswt.jar;C:Program FilesJavajdk1.8.0_161jrelibjsse.jar;C:Program FilesJavajdk1.8.0_161jrelibmanagement-agent.jar;C:Program FilesJavajdk1.8.0_161jrelibplugin.jar;C:Program FilesJavajdk1.8.0_161jrelibresources.jar;C:Program FilesJavajdk1.8.0_161jrelibrt.jar;E:workspacemchopintargetclasses;D:repositoryorgspringframeworkbootspring-boot-starter-web2.1.5.RELEASEspring-boot-starter-web-2.1.5.RELEASE.jar;D:repositoryorgspringframeworkbootspring-boot-starter2.1.5.RELEASEspring-boot-starter-2.1.5.RELEASE.jar;D:repositoryorgspringframeworkbootspring-boot-starter-logging2.1.5.RELEASEspring-boot-starter-logging-2.1.5.RELEASE.jar;D:repositorychqoslogbacklogback-classic1.2.3logback-classic-1.2.3.jar;D:repositorychqoslogbacklogback-core1.2.3logback-core-1.2.3.jar;D:repositoryorgapachelogginglog4jlog4j-to-slf4j2.11.2log4j-to-slf4j-2.11.2.jar;D:repositoryorgapachelogginglog4jlog4j-api2.11.2log4j-api-2.11.2.jar;D:repositoryorgslf4jjul-to-slf4j1.7.26jul-to-slf4j-1.7.26.jar;D:repositoryjavaxannotationjavax.annotation-api1.3.2javax.annotation-api-1.3.2.jar;D:repositoryorgyamlsnakeyaml1.23snakeyaml-1.23.jar;D:repositoryorgspringframeworkbootspring-boot-starter-json2.1.5.RELEASEspring-boot-starter-json-2.1.5.RELEASE.jar;D:repositorycomfasterxmljacksoncorejackson-databind2.9.8jackson-databind-2.9.8.jar;D:repositorycomfasterxmljacksoncorejackson-annotations2.9.0jackson-annotations-2.9.0.jar;D:repositorycomfasterxmljacksoncorejackson-core2.9.8jackson-core-2.9.8.jar;D:repositorycomfasterxmljacksondatatypejackson-datatype-jdk82.9.8jackson-datatype-jdk8-2.9.8.jar;D:repositorycomfasterxmljacksondatatypejackson-datatype-jsr3102.9.8jackson-datatype-jsr310-2.9.8.jar;D:repositorycomfasterxmljacksonmodulejackson-module-parameter-names2.9.8jackson-module-parameter-names-2.9.8.jar;D:repositoryorgspringframeworkbootspring-boot-starter-tomcat2.1.5.RELEASEspring-boot-starter-tomcat-2.1.5.RELEASE.jar;D:repositoryorgapachetomcatembedtomcat-embed-core9.0.19tomcat-embed-core-9.0.19.jar;D:repositoryorgapachetomcatembedtomcat-embed-el9.0.19tomcat-embed-el-9.0.19.jar;D:repositoryorgapachetomcatembedtomcat-embed-websocket9.0.19tomcat-embed-websocket-9.0.19.jar;D:repositoryorghibernatevalidatorhibernate-validator6.0.16.Finalhibernate-validator-6.0.16.Final.jar;D:repositoryjavaxvalidationvalidation-api2.0.1.Finalvalidation-api-2.0.1.Final.jar;D:repositoryorgjbossloggingjboss-logging3.3.2.Finaljboss-logging-3.3.2.Final.jar;D:repositorycomfasterxmlclassmate1.4.0classmate-1.4.0.jar;D:repositoryorgslf4jslf4j-api1.7.26slf4j-api-1.7.26.jar;D:repositoryorgspringframeworkspring-core5.1.7.RELEASEspring-core-5.1.7.RELEASE.jar;D:repositoryorgspringframeworkspring-jcl5.1.7.RELEASEspring-jcl-5.1.7.RELEASE.jar;D:repositoryorgspringframeworkspring-web5.1.7.RELEASEspring-web-5.1.7.RELEASE.jar;D:repositoryorgspringframeworkspring-beans5.1.7.RELEASEspring-beans-5.1.7.RELEASE.jar;D:repositoryorgspringframeworkspring-webmvc5.1.7.RELEASEspring-webmvc-5.1.7.RELEASE.jar;D:repositoryorgspringframeworkspring-aop5.1.7.RELEASEspring-aop-5.1.7.RELEASE.jar;D:repositoryorgspringframeworkspring-context5.1.7.RELEASEspring-context-5.1.7.RELEASE.jar;D:repositoryorgspringframeworkspring-expression5.1.7.RELEASEspring-expression-5.1.7.RELEASE.jar;D:repositoryorgmybatismybatis3.5.1mybatis-3.5.1.jar;D:repositoryorgspringframeworkbootspring-boot-starter-jdbc2.1.5.RELEASEspring-boot-starter-jdbc-2.1.5.RELEASE.jar;D:repositorycomzaxxerHikariCP3.2.0HikariCP-3.2.0.jar;D:repositoryorgspringframeworkspring-jdbc5.1.7.RELEASEspring-jdbc-5.1.7.RELEASE.jar;D:repositoryorgspringframeworkspring-tx5.1.7.RELEASEspring-tx-5.1.7.RELEASE.jar;D:repositoryorgmybatisspringbootmybatis-spring-boot-starter2.0.1mybatis-spring-boot-starter-2.0.1.jar;D:repositoryorgmybatisspringbootmybatis-spring-boot-autoconfigure2.0.1mybatis-spring-boot-autoconfigure-2.0.1.jar;D:repositoryorgmybatismybatis-spring2.0.1mybatis-spring-2.0.1.jar;D:repositorymysqlmysql-connector-java5.1.46mysql-connector-java-5.1.46.jar;D:repositoryorgspringframeworkbootspring-boot-devtools2.1.5.RELEASEspring-boot-devtools-2.1.5.RELEASE.jar;D:repositoryorgspringframeworkbootspring-boot2.1.5.RELEASEspring-boot-2.1.5.RELEASE.jar;D:repositoryorgspringframeworkbootspring-boot-autoconfigure2.1.5.RELEASEspring-boot-autoconfigure-2.1.5.RELEASE.jar;D:repositorycomaliyunaliyun-java-sdk-core4.0.6aliyun-java-sdk-core-4.0.6.jar;D:repositorycomgooglecodegsongson2.8.5gson-2.8.5.jar;D:repositoryorgapachehttpcomponentshttpclient4.5.8httpclient-4.5.8.jar;D:repositoryorgapachehttpcomponentshttpcore4.4.11httpcore-4.4.11.jar;D:repositorycommons-codeccommons-codec1.11commons-codec-1.11.jar;D:repositoryjavaxxmlbindjaxb-api2.3.1jaxb-api-2.3.1.jar;D:repositoryjavaxactivationjavax.activation-api1.2.0javax.activation-api-1.2.0.jar;D:repositorycomsunxmlbindjaxb-core2.1.14jaxb-core-2.1.14.jar;D:repositorycomsunxmlbindjaxb-impl2.1jaxb-impl-2.1.jar;D:repositoryjavaxactivationactivation1.1.1activation-1.1.1.jar;D:repositorycomaliyunaliyun-java-sdk-dysmsapi1.1.0aliyun-java-sdk-dysmsapi-1.1.0.jar;D:repositorycomalibabafastjson1.2.47fastjson-1.2.47.jar" com.xxp.mchopin.util.SmsDemo
Exception in thread "main" com.aliyuncs.exceptions.ClientException: MissingAccessKeyId : AccessKeyId is mandatory for this action.
RequestId : F58F1F9E-8D3F-44A3-A64E-E6B4BCB51BA1
	at com.aliyuncs.DefaultAcsClient.parseAcsResponse(DefaultAcsClient.java:230)
	at com.aliyuncs.DefaultAcsClient.getAcsResponse(DefaultAcsClient.java:134)
	at com.xxp.mchopin.util.SmsDemo.sendSms(SmsDemo.java:47)
	at com.xxp.mchopin.util.SmsDemo.main(SmsDemo.java:70)

Process finished with exit code 1

三、java.io.IOException: Broken pipe

认识 broken pipe
pipe 是管道的意思，管道里面是数据流，通常是从文件或网络套接字读取的数据。 当该管道从另一端突然关闭时，会发生数据突然中断，即是broken。 对于文件File来说，这可能是文件安装在已断开连接的光盘或远程网络上。 对于socket来说，可能是网络被拔出或另一端的进程崩溃。 在Java中，没有具体的BrokenPipeException。 将此类错误包含在另一个异常，例如java.io.IOException:Broken pipe

解决问题
其实当该异常产生的时候，对于服务端来说，并没有多少影响。因为可能是某个客户端突然中止了进程导致了该错误。但是为了程序能够美观、优雅，还是要在合适的地方捕获该异常，并处理一下。还有一种可能性就是程序里面有代码执行时间过长，用户等待时间过久，才会强行中止进程。那么这种情况下就需要去分析log中报异常的地方是经常发生在什么地方，合理优化该段代码，提升代码的运行速度，才能从根本上避免此类问题的再次发生。

四、java.net.MalformedURLException

URL url = new URL(param);

构建对象的时候，入参是null，导致URL转换失败。入参之前，进行非null判断，可避免此异常。

五、org.springframework.web.HttpMediaTypeNotSupportedException 六、java.lang.Exception: Test class should have exactly one public zero-argument constructor 七、java.time.format.DateTimeParseException

Exception in thread "main" java.time.format.DateTimeParseException: Text '2008-8-08 00:00:00' could not be parsed at index 5
    at java.time.format.DateTimeFormatter.parseResolved0(DateTimeFormatter.java:1949)
    at java.time.format.DateTimeFormatter.parse(DateTimeFormatter.java:1851)
    at java.time.LocalDateTime.parse(LocalDateTime.java:492)
    at com.yikesong.core.domain.money.model.finance.FinanceService.getInstants(FinanceService.java:179)
    at com.yikesong.core.domain.money.model.finance.FinanceService.main(FinanceService.java:167)

八、ResourceNotFoundException