1、異常核心提示：
The last packet successfully received from the server was 2,625 milliseconds ago. The last packet sent successfully to the server was 2,625 milliseconds ago.
2、詳細的錯誤提示：
The last packet successfully received from the server was 2,625 milliseconds ago. The last packet sent successfully to the server was 2,625 milliseconds ago.
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:422)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:425)
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:990)
at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3562)
at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3462)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3905)
at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2530)
at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2683)
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2495)
at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:1903)
at com.mysql.jdbc.PreparedStatement.execute(PreparedStatement.java:1242)
at com.alibaba.druid.pool.DruidPooledPreparedStatement.execute(DruidPooledPreparedStatement.java:497)
at org.apache.ibatis.executor.statement.PreparedStatementHandler.update(PreparedStatementHandler.java:47)
at org.apache.ibatis.executor.statement.RoutingStatementHandler.update(RoutingStatementHandler.java:74)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:497)
at org.apache.ibatis.plugin.Plugin.invoke(Plugin.java:63)
at com.sun.proxy.$Proxy81.update(Unknown Source)
at org.apache.ibatis.executor.SimpleExecutor.doUpdate(SimpleExecutor.java:50)
at org.apache.ibatis.executor.BaseExecutor.update(BaseExecutor.java:117)
at org.apache.ibatis.executor.CachingExecutor.update(CachingExecutor.java:76)
at org.apache.ibatis.session.defaults.DefaultSqlSession.update(DefaultSqlSession.java:198)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:497)
at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:433)
at com.sun.proxy.$Proxy64.update(Unknown Source)
at org.mybatis.spring.SqlSessionTemplate.update(SqlSessionTemplate.java:294)
at com.baomidou.mybatisplus.core.override.MybatisMapperMethod.execute(MybatisMapperMethod.java:69)
at com.baomidou.mybatisplus.core.override.MybatisMapperProxy.invoke(MybatisMapperProxy.java:61)
at com.sun.proxy.$Proxy74.resetNextExecuteTime(Unknown Source)
at org.spiderflow.core.service.SpiderFlowService.initJobs(SpiderFlowService.java:57)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:497)
at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor$LifecycleElement.invoke(InitDestroyAnnotationBeanPostProcessor.java:366)
at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor$LifecycleMetadata.invokeInitMethods(InitDestroyAnnotationBeanPostProcessor.java:309)
at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor.postProcessBeforeInitialization(InitDestroyAnnotationBeanPostProcessor.java:136)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyBeanPostProcessorsBeforeInitialization(AbstractAutowireCapableBeanFactory.java:416)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1686)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:573)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:495)
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:317)
at org.springframework.beans.factory.support.AbstractBeanFactory$$Lambda$133/11874854.getObject(Unknown Source)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:315)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199)
at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:251)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1135)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1062)
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:581)
at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:90)
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:370)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1336)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:572)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:495)
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:317)
at org.springframework.beans.factory.support.AbstractBeanFactory$$Lambda$133/11874854.getObject(Unknown Source)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:315)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:759)
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:867)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:548)
at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:142)
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:754)
at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:386)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:307)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1242)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1230)
at org.spiderflow.SpiderApplication.main(SpiderApplication.java:24)
Caused by: java.net.SocketException: Connection reset
at java.net.SocketInputStream.read(SocketInputStream.java:209)
at java.net.SocketInputStream.read(SocketInputStream.java:141)
at com.mysql.jdbc.util.ReadAheadInputStream.fill(ReadAheadInputStream.java:101)
at com.mysql.jdbc.util.ReadAheadInputStream.readFromUnderlyingStreamIfNecessary(ReadAheadInputStream.java:144)
at com.mysql.jdbc.util.ReadAheadInputStream.read(ReadAheadInputStream.java:174)
at com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:3011)
at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3472)
... 71 common frames omitted
3、原因分析：
從錯誤提示資訊可知，最後一次成功連線資料庫是 2,625 毫秒之前，說明現在已經無法連線到 MySQL 資料庫了，那麼我們就可以進一步分析是什麼原因導致的 MySQL 資料庫不可連線？
是 MySQL 停止服務了？還是網路中斷了？
首先我們可以檢查下 MySQL 服務是否正常，如何正常則檢查網路是否暢通，如果不暢通則排查路由器等裝置。
在硬體沒有問題的情況下通常是 MySQL 停止服務了。
4、解決辦法：
經檢查發現是 MySQL 服務停止了，那麼就將其啟動起來。