概述

最近在前台导入3000条记录时，经常发现只导入大概500条记录，然后就会报ERROR TransactionInterceptor - Application exception overridden by rollback exception的问题。下面记录一下解决过程，以作备忘！

思路

这里主要是由于连接时间过长，失效所致。即，程序获取到的连接已经失效了，而拿一个失效的连接再次请求就会报那样的异常。

1、查看应用日志

可以看到都是在跟后端数据库连接时断开导致

具体信息如下：

java.sql.SQLNonTransientConnectionException: No operations allowed after connection closed.	at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:110) ~[mysql-connector-java-8.0.13.jar!/:8.0.13]	at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:97) ~[mysql-connector-java-8.0.13.jar!/:8.0.13]	at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:89) ~[mysql-connector-java-8.0.13.jar!/:8.0.13]	at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:63) ~[mysql-connector-java-8.0.13.jar!/:8.0.13]	at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:73) ~[mysql-connector-java-8.0.13.jar!/:8.0.13]	at com.mysql.cj.jdbc.exceptions.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:73) ~[mysql-connector-java-8.0.13.jar!/:8.0.13]	at com.mysql.cj.jdbc.ConnectionImpl.rollback(ConnectionImpl.java:1875) ~[mysql-connector-java-8.0.13.jar!/:8.0.13]	at com.zaxxer.hikari.pool.ProxyConnection.rollback(ProxyConnection.java:370) ~[HikariCP-3.2.0.jar!/:na]	at com.zaxxer.hikari.pool.HikariProxyConnection.rollback(HikariProxyConnection.java) [HikariCP-3.2.0.jar!/:na]	at org.springframework.jdbc.datasource.DataSourceTransactionManager.doRollback(DataSourceTransactionManager.java:344) [spring-jdbc-5.1.5.RELEASE.jar!/:5.1.5.RELEASE]	at org.springframework.transaction.support.AbstractPlatformTransactionManager.processRollback(AbstractPlatformTransactionManager.java:838) [spring-tx-5.1.5.RELEASE.jar!/:5.1.5.RELEASE]	at org.springframework.transaction.support.AbstractPlatformTransactionManager.rollback(AbstractPlatformTransactionManager.java:812) [spring-tx-5.1.5.RELEASE.jar!/:5.1.5.RELEASE]	at org.springframework.transaction.support.TransactionTemplate.rollbackOnException(TransactionTemplate.java:168) [spring-tx-5.1.5.RELEASE.jar!/:5.1.5.RELEASE]	at org.springframework.transaction.support.TransactionTemplate.execute(TransactionTemplate.java:144) [spring-tx-5.1.5.RELEASE.jar!/:5.1.5.RELEASE]	at logwire.web.service.ActionContext$TransactionExecutor.doWithoutResult(ActionContext.java:716) [logwire-web-1.0-SNAPSHOT.jar!/:1.0-SNAPSHOT]	at logwire.web.service.ActionContext.doInNewTransactionWithoutResult(ActionContext.java:561) [logwire-web-1.0-SNAPSHOT.jar!/:1.0-SNAPSHOT]	at logwire.web.service.task.run.impl.DefaultTaskRunner.doTaskInner(DefaultTaskRunner.java:85) [logwire-web-1.0-SNAPSHOT.jar!/:1.0-SNAPSHOT]	at logwire.web.service.task.run.impl.DefaultTaskRunner.doTaskInnerWithMetric(DefaultTaskRunner.java:130) [logwire-web-1.0-SNAPSHOT.jar!/:1.0-SNAPSHOT]	at logwire.web.service.task.run.impl.DefaultTaskRunner.doTask(DefaultTaskRunner.java:176) [logwire-web-1.0-SNAPSHOT.jar!/:1.0-SNAPSHOT]	at logwire.web.service.task.execute.TaskExecuteService.doTask(TaskExecuteService.java:35) [logwire-web-1.0-SNAPSHOT.jar!/:1.0-SNAPSHOT]	at logwire.web.service.task.execute.redisson.impl.RedissonTaskImpl.doTask(RedissonTaskImpl.java:22) [logwire-web-1.0-SNAPSHOT.jar!/:1.0-SNAPSHOT]	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_102]	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_102]	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_102]	at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_102]	at org.redisson.RedissonRemoteService.invokeMethod(RedissonRemoteService.java:360) [redisson-3.11.3.jar!/:3.11.3]	at org.redisson.RedissonRemoteService.lambda$executeMethod$4(RedissonRemoteService.java:329) [redisson-3.11.3.jar!/:3.11.3]	at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) ~[na:1.8.0_102]	at java.util.concurrent.FutureTask.run(FutureTask.java:266) ~[na:1.8.0_102]	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) ~[na:1.8.0_102]	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) ~[na:1.8.0_102]	at java.lang.Thread.run(Thread.java:745) ~[na:1.8.0_102]Caused by: com.mysql.cj.exceptions.ConnectionIsClosedException: No operations allowed after connection closed.	at sun.reflect.GeneratedConstructorAccessor129.newInstance(Unknown Source) ~[na:na]	at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) ~[na:1.8.0_102]	at java.lang.reflect.Constructor.newInstance(Constructor.java:423) ~[na:1.8.0_102]	at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:61) ~[mysql-connector-java-8.0.13.jar!/:8.0.13]	at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:105) ~[mysql-connector-java-8.0.13.jar!/:8.0.13]	at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:151) ~[mysql-connector-java-8.0.13.jar!/:8.0.13]	at com.mysql.cj.NativeSession.checkClosed(NativeSession.java:1259) ~[mysql-connector-java-8.0.13.jar!/:8.0.13]	at com.mysql.cj.jdbc.ConnectionImpl.checkClosed(ConnectionImpl.java:575) ~[mysql-connector-java-8.0.13.jar!/:8.0.13]	at com.mysql.cj.jdbc.ConnectionImpl.rollback(ConnectionImpl.java:1829) ~[mysql-connector-java-8.0.13.jar!/:8.0.13]	... 25 common frames omittedCaused by: com.mysql.cj.exceptions.CJCommunicationsException: Communications link failureThe last packet successfully received from the server was 35,661 milliseconds ago. The last packet sent successfully to the server was 35,662 milliseconds ago.	at sun.reflect.GeneratedConstructorAccessor126.newInstance(Unknown Source) ~[na:na]	at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) ~[na:1.8.0_102]	at java.lang.reflect.Constructor.newInstance(Constructor.java:423) ~[na:1.8.0_102]	at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:61) ~[mysql-connector-java-8.0.13.jar!/:8.0.13]	at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:105) ~[mysql-connector-java-8.0.13.jar!/:8.0.13]	at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:151) ~[mysql-connector-java-8.0.13.jar!/:8.0.13]	at com.mysql.cj.exceptions.ExceptionFactory.createCommunicationsException(ExceptionFactory.java:167) ~[mysql-connector-java-8.0.13.jar!/:8.0.13]	at com.mysql.cj.protocol.a.NativeProtocol.readMessage(NativeProtocol.java:555) ~[mysql-connector-java-8.0.13.jar!/:8.0.13]	at com.mysql.cj.protocol.a.NativeProtocol.checkErrorMessage(NativeProtocol.java:725) ~[mysql-connector-java-8.0.13.jar!/:8.0.13]	at com.mysql.cj.protocol.a.NativeProtocol.sendCommand(NativeProtocol.java:664) ~[mysql-connector-java-8.0.13.jar!/:8.0.13]	at com.mysql.cj.protocol.a.NativeProtocol.sendQueryPacket(NativeProtocol.java:979) ~[mysql-connector-java-8.0.13.jar!/:8.0.13]	at com.mysql.cj.NativeSession.execSQL(NativeSession.java:1153) ~[mysql-connector-java-8.0.13.jar!/:8.0.13]	at com.mysql.cj.jdbc.ClientPreparedStatement.executeInternal(ClientPreparedStatement.java:951) ~[mysql-connector-java-8.0.13.jar!/:8.0.13]	at com.mysql.cj.jdbc.ClientPreparedStatement.executeUpdateInternal(ClientPreparedStatement.java:1113) ~[mysql-connector-java-8.0.13.jar!/:8.0.13]	at com.mysql.cj.jdbc.ClientPreparedStatement.executeUpdateInternal(ClientPreparedStatement.java:1061) ~[mysql-connector-java-8.0.13.jar!/:8.0.13]	at com.mysql.cj.jdbc.ClientPreparedStatement.executeLargeUpdate(ClientPreparedStatement.java:1381) ~[mysql-connector-java-8.0.13.jar!/:8.0.13]	at com.mysql.cj.jdbc.ClientPreparedStatement.executeUpdate(ClientPreparedStatement.java:1046) ~[mysql-connector-java-8.0.13.jar!/:8.0.13]	at com.zaxxer.hikari.pool.ProxyPreparedStatement.executeUpdate(ProxyPreparedStatement.java:61) ~[HikariCP-3.2.0.jar!/:na]	at com.zaxxer.hikari.pool.HikariProxyPreparedStatement.executeUpdate(HikariProxyPreparedStatement.java) ~[HikariCP-3.2.0.jar!/:na]	at org.springframework.jdbc.core.JdbcTemplate.lambda$update$0(JdbcTemplate.java:867) ~[spring-jdbc-5.1.5.RELEASE.jar!/:5.1.5.RELEASE]	at org.springframework.jdbc.core.JdbcTemplate.execute(JdbcTemplate.java:617) ~[spring-jdbc-5.1.5.RELEASE.jar!/:5.1.5.RELEASE]	at org.springframework.jdbc.core.JdbcTemplate.update(JdbcTemplate.java:862) ~[spring-jdbc-5.1.5.RELEASE.jar!/:5.1.5.RELEASE]	at org.springframework.jdbc.core.JdbcTemplate.update(JdbcTemplate.java:917) ~[spring-jdbc-5.1.5.RELEASE.jar!/:5.1.5.RELEASE]	at logwire.web.service.query.sql.QueryDataSetManager.insertModelRow(QueryDataSetManager.java:419) ~[logwire-web-1.0-SNAPSHOT.jar!/:1.0-SNAPSHOT]	at logwire.web.service.query.sql.QueryDataSetManager.saveModelDataSet(QueryDataSetManager.java:140) ~[logwire-web-1.0-SNAPSHOT.jar!/:1.0-SNAPSHOT]	at logwire.web.service.query.sql.QueryDataSetManager.saveModelDataSet(QueryDataSetManager.java:104) ~[logwire-web-1.0-SNAPSHOT.jar!/:1.0-SNAPSHOT]	at logwire.web.service.query.sql.QueryDataSetManager.insert(QueryDataSetManager.java:272) ~[logwire-web-1.0-SNAPSHOT.jar!/:1.0-SNAPSHOT]	at logwire.web.service.query.QueryService.insert(QueryService.java:183) ~[logwire-web-1.0-SNAPSHOT.jar!/:1.0-SNAPSHOT]	at logwire.web.service.query.QueryService.insert(QueryService.java:163) ~[logwire-web-1.0-SNAPSHOT.jar!/:1.0-SNAPSHOT]	at jdk.nashorn.internal.scripts.Script$Recompilation$203$16161AAAAAAA$importHandlers.L:1$insertLog(config/custom_js/importHandlers.js:449) ~[na:na]	at jdk.nashorn.internal.scripts.Script$Recompilation$198$9472A$tasks.L:1$handleImport$L:256(config/custom_js/tasks.js:273) ~[na:na]	at jdk.nashorn.javaadapters.java.util.function.Consumer.accept(Unknown Source) ~[na:na]	at java.util.ArrayList.forEach(ArrayList.java:1249) ~[na:1.8.0_102]	at jdk.nashorn.internal.scripts.Script$Recompilation$196$9015AAA$tasks.L:1$handleImport(config/custom_js/tasks.js:256) ~[na:na]	at jdk.nashorn.internal.scripts.Script$Recompilation$195$8841AAA$tasks.L:1$partsImportDD(config/custom_js/tasks.js:239) ~[na:na]	at jdk.nashorn.internal.runtime.ScriptFunctionData.invoke(ScriptFunctionData.java:643) ~[nashorn.jar:na]	at jdk.nashorn.internal.runtime.ScriptFunction.invoke(ScriptFunction.java:494) ~[nashorn.jar:na]	at jdk.nashorn.internal.runtime.ScriptRuntime.apply(ScriptRuntime.java:393) ~[nashorn.jar:na]	at jdk.nashorn.api.scripting.ScriptObjectMirror.callMember(ScriptObjectMirror.java:199) ~[nashorn.jar:na]	at logwire.core.meta.task.ScriptTask.doTask(ScriptTask.java:24) ~[logwire-web-1.0-SNAPSHOT.jar!/:1.0-SNAPSHOT]	at logwire.web.service.task.run.impl.DefaultTaskRunner$1.doInTransactionWithoutResult(DefaultTaskRunner.java:88) ~[logwire-web-1.0-SNAPSHOT.jar!/:1.0-SNAPSHOT]	at org.springframework.transaction.support.TransactionCallbackWithoutResult.doInTransaction(TransactionCallbackWithoutResult.java:36) ~[spring-tx-5.1.5.RELEASE.jar!/:5.1.5.RELEASE]	at org.springframework.transaction.support.TransactionTemplate.execute(TransactionTemplate.java:140) [spring-tx-5.1.5.RELEASE.jar!/:5.1.5.RELEASE]	... 18 common frames omittedCaused by: java.io.EOFException: Can not read response from server. Expected to read 4 bytes, read 0 bytes before connection was unexpectedly lost.	at com.mysql.cj.protocol.FullReadInputStream.readFully(FullReadInputStream.java:67) ~[mysql-connector-java-8.0.13.jar!/:8.0.13]	at com.mysql.cj.protocol.a.SimplePacketReader.readHeader(SimplePacketReader.java:63) ~[mysql-connector-java-8.0.13.jar!/:8.0.13]	at com.mysql.cj.protocol.a.SimplePacketReader.readHeader(SimplePacketReader.java:45) ~[mysql-connector-java-8.0.13.jar!/:8.0.13]	at com.mysql.cj.protocol.a.TimeTrackingPacketReader.readHeader(TimeTrackingPacketReader.java:52) ~[mysql-connector-java-8.0.13.jar!/:8.0.13]	at com.mysql.cj.protocol.a.TimeTrackingPacketReader.readHeader(TimeTrackingPacketReader.java:41) ~[mysql-connector-java-8.0.13.jar!/:8.0.13]	at com.mysql.cj.protocol.a.MultiPacketReader.readHeader(MultiPacketReader.java:54) ~[mysql-connector-java-8.0.13.jar!/:8.0.13]	at com.mysql.cj.protocol.a.MultiPacketReader.readHeader(MultiPacketReader.java:44) ~[mysql-connector-java-8.0.13.jar!/:8.0.13]	at com.mysql.cj.protocol.a.NativeProtocol.readMessage(NativeProtocol.java:549) ~[mysql-connector-java-8.0.13.jar!/:8.0.13]	... 53 common frames omitted

2、直连mysql测试

由于后端数据库是用mycat+mysql主从做的读写分离，影响因素比较多，所以需先去掉影响的一些因素，这里先直连mysql数据库测试，绕过mycat

经过业务测试发现可以导入成功，这样问题就在mycat上了

3、mycat关闭读写分离

关闭mycat的读写分离后导入3000条可以导入2700条，但还有部分失败。

mycat日志如下：

INFO [$_NIOREACTOR-1-RW] (io.mycat.net.AbstractConnection.close(AbstractConnection.java:520)) - close connection,reason:stream closed ,ServerConnection [id=55, schema=tms_prod, host=, user=root,txIsolation=3, autocommit=true, schema=tms_prod, executeSql=null]INFO [$_NIOREACTOR-2-RW] (io.mycat.net.AbstractConnection.close(AbstractConnection.java:520)) - close connection,reason:stream closed ,ServerConnection [id=56, schema=tms_prod, host=, u

4、修改应用配置

经过查找资料和分析，得出该问题主要是由于连接时间过长，失效所致，既然程序获取的连接已经失效了，那么对于失效的连接就不应该使用，而应该再次获取有效的连接。增加配置如下：

spring.datasource.validation-query=SELECT 1

修改后让业务重新测试，导入正常，问题解决。

总结

当数据库连接池中的连接被创建而长时间不使用的情况下，该连接会自动回收并失效，但客户端并不知道，在进行数据库操作时仍然使用的是无效的数据库连接，这样，就导致客户端程序报“ java.sql.SQLException: Io 异常: Connection reset by peer”或“java.sql.SQLException 关闭的连接”异常，加上spring.datasource.validation-query=SELECT 1配置后，客户端在使用一个无效的连接时会先对该连接进行测试，如果发现该连接已经无效，则重新从连接池获取有效数据库连接来使用。

觉得有用的朋友多帮忙转发哦！后面会分享更多devops和DBA方面的内容，感兴趣的朋友可以关注下~