java.sql.SQLException: connection holder is null

Cause: java.sql.SQLException: connection holder is null

; uncategorized SQLException for SQL []; SQL state [null]; error code [0]; connection holder is null; nested exception is java.sql.SQLException: connection holder is null
at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:83)
at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:80)
at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:80)
at org.mybatis.spring.MyBatisExceptionTranslator.translateExceptionIfPossible(MyBatisExceptionTranslator.java:75)
at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:447)
at com.sun.proxy.$Proxy72.selectOne(Unknown Source)
at org.mybatis.spring.SqlSessionTemplate.selectOne(SqlSessionTemplate.java:167)
at org.apache.ibatis.binding.MapperMethod.execute(MapperMethod.java:82)
at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:53)
at com.sun.proxy.$Proxy168.getIssueTotalValid(Unknown Source)
at com.alibaba.swork.info.common.service.quality.impl.QualityDataOfTeamServiceImpl.syncQualityDataOfTeam(QualityDataOfTeamServiceImpl.java:63)
at com.alibaba.swork.info.common.service.quality.impl.QualityDataOfTeamServiceImpl.saveQualityDataOfTeamDTS(QualityDataOfTeamServiceImpl.java:48)
at com.alibaba.swork.info.common.service.quality.impl.QualityDataOfTeamServiceImpl$$FastClassByCGLIB$$8eb081d2.invoke(<generated>)
at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204)
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:698)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:150)
at org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:96)
at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:260)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:94)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:91)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:631)
at com.alibaba.swork.info.common.service.quality.impl.QualityDataOfTeamServiceImpl$$EnhancerByCGLIB$$7e8e4849.saveQualityDataOfTeamDTS(<generated>)
at com.alibaba.swork.info.common.biz.job.dts.QualityDataOfTeamJob.job(QualityDataOfTeamJob.java:24)
at com.alibaba.swork.info.common.biz.job.dts.QualityDataOfTeamJob.onProcess(QualityDataOfTeamJob.java:20)
at com.alibaba.swork.info.common.biz.job.dts.AbstractDTSJob.process(AbstractDTSJob.java:28)
at com.alibaba.dts.client.executor.simple.processor.SimpleTaskProcessor.executeTask(SimpleTaskProcessor.java:146)
at com.alibaba.dts.client.executor.simple.processor.SimpleTaskProcessor.run(SimpleTaskProcessor.java:100)
Caused by: java.sql.SQLException: connection holder is null
at com.alibaba.druid.pool.DruidPooledConnection.checkStateInternal(DruidPooledConnection.java:1120)
at com.alibaba.druid.pool.DruidPooledConnection.checkState(DruidPooledConnection.java:1113)
at com.alibaba.druid.pool.DruidPooledConnection.getHoldability(DruidPooledConnection.java:969)
at com.taobao.tddl.atom.jdbc.TConnectionWrapper.getHoldability(TConnectionWrapper.java:145)
at com.taobao.tddl.group.jdbc.TGroupPreparedStatement.createPreparedStatementInternal(TGroupPreparedStatement.java:78)
at com.taobao.tddl.group.jdbc.TGroupPreparedStatement.executeQueryOnConnection(TGroupPreparedStatement.java:120)
at com.taobao.tddl.group.jdbc.TGroupStatement.executeQuery(TGroupStatement.java:488)
at com.taobao.tddl.group.jdbc.TGroupStatement.executeInternal(TGroupStatement.java:131)
at com.taobao.tddl.group.jdbc.TGroupStatement.execute(TGroupStatement.java:101)
at com.taobao.tddl.group.jdbc.TGroupPreparedStatement.execute(TGroupPreparedStatement.java:104)
at org.apache.ibatis.executor.statement.PreparedStatementHandler.query(PreparedStatementHandler.java:63)
at org.apache.ibatis.executor.statement.RoutingStatementHandler.query(RoutingStatementHandler.java:79)
at org.apache.ibatis.executor.SimpleExecutor.doQuery(SimpleExecutor.java:63)
at org.apache.ibatis.executor.BaseExecutor.queryFromDatabase(BaseExecutor.java:324)
at org.apache.ibatis.executor.BaseExecutor.query(BaseExecutor.java:156)
at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:109)
at com.github.pagehelper.PageInterceptor.intercept(PageInterceptor.java:142)
at org.apache.ibatis.plugin.Plugin.invoke(Plugin.java:61)
at com.sun.proxy.$Proxy219.query(Unknown Source)
at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:148)
at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:141)
at org.apache.ibatis.session.defaults.DefaultSqlSession.selectOne(DefaultSqlSession.java:77)
at sun.reflect.GeneratedMethodAccessor123.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:434)
... 24 more
Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure

The last packet successfully received from the server was 12,014 milliseconds ago. The last packet sent successfully to the server was 12,012 milliseconds ago.