Spring，MySQL和Hibernate：如果系统在8小时内未使用，则会出现数据库错误

我正在开发Spring，MySQL和Hibernate项目，如果项目在8小时内没有使用，我会收到以下错误。 有人可以告诉我为什么。 看起来如果我重启服务器一切都很好，直到晚上或者如果没有人在中午使用系统几个小时。 有人请帮助我，我刚刚在我的一些项目中发现了这个问题所以我必须在许多项目中犯同样的错误..请帮忙

这是我的java代码的一个例子，我错过了一些东西：

public void saveVisit(VisitModel visit) throws Exception { LOGGER.debug("[" + visit.toString() + "]"); sessionFactory.getCurrentSession().saveOrUpdate(visit); } @SuppressWarnings("unchecked") public School_lookupModel getSchoolInformation(String schoolCode) { return (School_lookupModel) sessionFactory.getCurrentSession() .createCriteria(School_lookupModel.class) .add( Restrictions.like("school", schoolCode)) .uniqueResult(); } 

以下是错误的控制台输出：

 2012-09-06 08:00:07,088 [http-8080-2] WARN org.hibernate.util.JDBCExceptionReporter - SQL Error: 0, SQLState: 08S01 2012-09-06 08:00:07,088 [http-8080-2] ERROR org.hibernate.util.JDBCExceptionReporter - Communications link failure due to underlying exception: ** BEGIN NESTED EXCEPTION ** java.io.EOFException STACKTRACE: java.io.EOFException at com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:1963) at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:2375) at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:2874) at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1623) at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:1715) at com.mysql.jdbc.Connection.execSQL(Connection.java:3249) at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:1268) at com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:1403) at org.apache.commons.dbcp.DelegatingPreparedStatement.executeQuery(DelegatingPreparedStatement.java:93) at org.hibernate.jdbc.AbstractBatcher.getResultSet(AbstractBatcher.java:208) at org.hibernate.loader.Loader.getResultSet(Loader.java:1849) at org.hibernate.loader.Loader.doQuery(Loader.java:718) at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:270) at org.hibernate.loader.Loader.doList(Loader.java:2294) at org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2172) at org.hibernate.loader.Loader.list(Loader.java:2167) at org.hibernate.loader.criteria.CriteriaLoader.list(CriteriaLoader.java:119) at org.hibernate.impl.SessionImpl.list(SessionImpl.java:1706) at org.hibernate.impl.CriteriaImpl.list(CriteriaImpl.java:347) at org.uftwf.schoolvisit.dao.SchoolVisitDAOImpl.getSelectableReporters(SchoolVisitDAOImpl.java:56) at org.uftwf.schoolvisit.service.SchoolVisitServiceImpl.getSelectableReporters(SchoolVisitServiceImpl.java:130) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:616) at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:318) at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:183) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:150) at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:110) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172) at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:202) at $Proxy36.getSelectableReporters(Unknown Source) at org.uftwf.schoolvisit.controller.swf.FlowActions.initializeSelectableReports(FlowActions.java:57) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:616) at org.springframework.expression.spel.support.ReflectiveMethodExecutor.execute(ReflectiveMethodExecutor.java:69) at org.springframework.expression.spel.ast.MethodReference.getValueInternal(MethodReference.java:84) at org.springframework.expression.spel.ast.CompoundExpression.getValueInternal(CompoundExpression.java:57) at org.springframework.expression.spel.ast.SpelNodeImpl.getTypedValue(SpelNodeImpl.java:102) at org.springframework.expression.spel.standard.SpelExpression.getValue(SpelExpression.java:97) at org.springframework.binding.expression.spel.SpringELExpression.getValue(SpringELExpression.java:84) at org.springframework.webflow.action.EvaluateAction.doExecute(EvaluateAction.java:75) at org.springframework.webflow.action.AbstractAction.execute(AbstractAction.java:188) at org.springframework.webflow.execution.AnnotatedAction.execute(AnnotatedAction.java:145) at org.springframework.webflow.execution.ActionExecutor.execute(ActionExecutor.java:51) at org.springframework.webflow.engine.ActionList.execute(ActionList.java:155) at org.springframework.webflow.engine.Flow.start(Flow.java:534) at org.springframework.webflow.engine.impl.FlowExecutionImpl.start(FlowExecutionImpl.java:366) at org.springframework.webflow.engine.impl.FlowExecutionImpl.start(FlowExecutionImpl.java:222) at org.springframework.webflow.executor.FlowExecutorImpl.launchExecution(FlowExecutorImpl.java:140) at org.springframework.webflow.mvc.servlet.FlowHandlerAdapter.handle(FlowHandlerAdapter.java:193) at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:923) at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:852) at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:882) at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:778) at javax.servlet.http.HttpServlet.service(HttpServlet.java:617) at javax.servlet.http.HttpServlet.service(HttpServlet.java:717) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293) at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:859) at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:602) at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489) at java.lang.Thread.run(Thread.java:679) ** END NESTED EXCEPTION ** Last packet sent to the server was 13 ms ago. 2012-09-06 08:00:07,089 [http-8080-2] WARN org.hibernate.util.JDBCExceptionReporter - SQL Error: 0, SQLState: null 2012-09-06 08:00:07,089 [http-8080-2] ERROR org.hibernate.util.JDBCExceptionReporter - Already closed. 2012-09-06 08:00:07,089 [http-8080-2] WARN org.hibernate.util.JDBCExceptionReporter - SQL Error: 0, SQLState: null 2012-09-06 08:00:07,089 [http-8080-2] ERROR org.hibernate.util.JDBCExceptionReporter - Already closed. Sep 6, 2012 8:00:07 AM org.apache.catalina.core.StandardWrapperValve invoke SEVERE: Servlet.service() for servlet spring threw exception com.mysql.jdbc.CommunicationsException: Communications link failure due to underlying exception: ** BEGIN NESTED EXCEPTION ** java.io.EOFException STACKTRACE: java.io.EOFException at com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:1963) at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:2375) at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:2874) at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1623) at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:1715) at com.mysql.jdbc.Connection.execSQL(Connection.java:3249) at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:1268) at com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:1403) at org.apache.commons.dbcp.DelegatingPreparedStatement.executeQuery(DelegatingPreparedStatement.java:93) at org.hibernate.jdbc.AbstractBatcher.getResultSet(AbstractBatcher.java:208) at org.hibernate.loader.Loader.getResultSet(Loader.java:1849) at org.hibernate.loader.Loader.doQuery(Loader.java:718) at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:270) at org.hibernate.loader.Loader.doList(Loader.java:2294) at org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2172) at org.hibernate.loader.Loader.list(Loader.java:2167) at org.hibernate.loader.criteria.CriteriaLoader.list(CriteriaLoader.java:119) at org.hibernate.impl.SessionImpl.list(SessionImpl.java:1706) at org.hibernate.impl.CriteriaImpl.list(CriteriaImpl.java:347) at org.uftwf.schoolvisit.dao.SchoolVisitDAOImpl.getSelectableReporters(SchoolVisitDAOImpl.java:56) at org.uftwf.schoolvisit.service.SchoolVisitServiceImpl.getSelectableReporters(SchoolVisitServiceImpl.java:130) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:616) at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:318) at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:183) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:150) at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:110) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172) at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:202) at $Proxy36.getSelectableReporters(Unknown Source) at org.uftwf.schoolvisit.controller.swf.FlowActions.initializeSelectableReports(FlowActions.java:57) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:616) at org.springframework.expression.spel.support.ReflectiveMethodExecutor.execute(ReflectiveMethodExecutor.java:69) at org.springframework.expression.spel.ast.MethodReference.getValueInternal(MethodReference.java:84) at org.springframework.expression.spel.ast.CompoundExpression.getValueInternal(CompoundExpression.java:57) at org.springframework.expression.spel.ast.SpelNodeImpl.getTypedValue(SpelNodeImpl.java:102) at org.springframework.expression.spel.standard.SpelExpression.getValue(SpelExpression.java:97) at org.springframework.binding.expression.spel.SpringELExpression.getValue(SpringELExpression.java:84) at org.springframework.webflow.action.EvaluateAction.doExecute(EvaluateAction.java:75) at org.springframework.webflow.action.AbstractAction.execute(AbstractAction.java:188) at org.springframework.webflow.execution.AnnotatedAction.execute(AnnotatedAction.java:145) at org.springframework.webflow.execution.ActionExecutor.execute(ActionExecutor.java:51) at org.springframework.webflow.engine.ActionList.execute(ActionList.java:155) at org.springframework.webflow.engine.Flow.start(Flow.java:534) at org.springframework.webflow.engine.impl.FlowExecutionImpl.start(FlowExecutionImpl.java:366) at org.springframework.webflow.engine.impl.FlowExecutionImpl.start(FlowExecutionImpl.java:222) at org.springframework.webflow.executor.FlowExecutorImpl.launchExecution(FlowExecutorImpl.java:140) at org.springframework.webflow.mvc.servlet.FlowHandlerAdapter.handle(FlowHandlerAdapter.java:193) at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:923) at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:852) at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:882) at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:778) at javax.servlet.http.HttpServlet.service(HttpServlet.java:617) at javax.servlet.http.HttpServlet.service(HttpServlet.java:717) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293) at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:859) at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:602) at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489) at java.lang.Thread.run(Thread.java:679) ** END NESTED EXCEPTION ** Last packet sent to the server was 13 ms ago. at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:2586) at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:2874) at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1623) at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:1715) at com.mysql.jdbc.Connection.execSQL(Connection.java:3249) at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:1268) at com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:1403) at org.apache.commons.dbcp.DelegatingPreparedStatement.executeQuery(DelegatingPreparedStatement.java:93) at org.hibernate.jdbc.AbstractBatcher.getResultSet(AbstractBatcher.java:208) at org.hibernate.loader.Loader.getResultSet(Loader.java:1849) at org.hibernate.loader.Loader.doQuery(Loader.java:718) at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:270) at org.hibernate.loader.Loader.doList(Loader.java:2294) at org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2172) at org.hibernate.loader.Loader.list(Loader.java:2167) at org.hibernate.loader.criteria.CriteriaLoader.list(CriteriaLoader.java:119) at org.hibernate.impl.SessionImpl.list(SessionImpl.java:1706) at org.hibernate.impl.CriteriaImpl.list(CriteriaImpl.java:347) at org.uftwf.schoolvisit.dao.SchoolVisitDAOImpl.getSelectableReporters(SchoolVisitDAOImpl.java:56) at org.uftwf.schoolvisit.service.SchoolVisitServiceImpl.getSelectableReporters(SchoolVisitServiceImpl.java:130) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:616) at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:318) at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:183) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:150) at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:110) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172) at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:202) at $Proxy36.getSelectableReporters(Unknown Source) at org.uftwf.schoolvisit.controller.swf.FlowActions.initializeSelectableReports(FlowActions.java:57) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:616) at org.springframework.expression.spel.support.ReflectiveMethodExecutor.execute(ReflectiveMethodExecutor.java:69) at org.springframework.expression.spel.ast.MethodReference.getValueInternal(MethodReference.java:84) at org.springframework.expression.spel.ast.CompoundExpression.getValueInternal(CompoundExpression.java:57) at org.springframework.expression.spel.ast.SpelNodeImpl.getTypedValue(SpelNodeImpl.java:102) at org.springframework.expression.spel.standard.SpelExpression.getValue(SpelExpression.java:97) at org.springframework.binding.expression.spel.SpringELExpression.getValue(SpringELExpression.java:84) at org.springframework.webflow.action.EvaluateAction.doExecute(EvaluateAction.java:75) at org.springframework.webflow.action.AbstractAction.execute(AbstractAction.java:188) at org.springframework.webflow.execution.AnnotatedAction.execute(AnnotatedAction.java:145) at org.springframework.webflow.execution.ActionExecutor.execute(ActionExecutor.java:51) at org.springframework.webflow.engine.ActionList.execute(ActionList.java:155) at org.springframework.webflow.engine.Flow.start(Flow.java:534) at org.springframework.webflow.engine.impl.FlowExecutionImpl.start(FlowExecutionImpl.java:366) at org.springframework.webflow.engine.impl.FlowExecutionImpl.start(FlowExecutionImpl.java:222) at org.springframework.webflow.executor.FlowExecutorImpl.launchExecution(FlowExecutorImpl.java:140) at org.springframework.webflow.mvc.servlet.FlowHandlerAdapter.handle(FlowHandlerAdapter.java:193) at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:923) at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:852) at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:882) at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:778) at javax.servlet.http.HttpServlet.service(HttpServlet.java:617) at javax.servlet.http.HttpServlet.service(HttpServlet.java:717) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293) at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:859) at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:602) at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489) at java.lang.Thread.run(Thread.java:679) 

Answer 1

使用c3p0作为池，它可以用于生产用途

使用此参数（您可以修改以优化），这将保持您的连接处于活动状态

 1800 100 

编辑您还可以通过以下参数增加8小时限制

http://dev.mysql.com/doc/refman/5.0/en/server-system-variables.html#sysvar_wait_timeout

Answer 2

发生这种情况是因为mysql在8小时后丢失连接。 解决此问题的一种方法是使用其他post中提到的c3p0 。 另一种方法是在jdbc url中使用mysql的autoReconnect=true属性。 在连接上发出下一个查询时，此属性将尝试重新连接。

更多信息： http ： //dev.mysql.com/doc/refman/5.0/en/connector-j-reference-configuration-properties.html

请注意， autoReconnect仅处理连接部分。 它不会自动重新执行查询。 您必须通过捕获SQLException并在代码中重试查询来自行处理。 我最近碰到了这个，它对我有用。

Answer 3

会发生什么是您的应用尝试使用已关闭的连接。 这是因为Mysql会自动关闭连接，但您的应用程序不知道这一点。 主要问题是您正确关闭了您使用的连接。 在Hibernate术语中，这意味着您没有关闭Session。 检查您的代码，确保在使用后关闭每个连接。 如果您正在使用Spring-Hibernate集成，请查看有关集成的Spring文档。