MySQL Exception

[hethcox]

I'm running Activiti 5.11 on Server 2008 with MySQL 5.6. I wrote a custom app that uses Activiti engine. After the system sets idle for several hours I get the exception below. I've tried monkeying around with the database URL, but no luck. Can anyone suggest a solution? I think the DB is getting swapped out and can't recover when it's swapped back in. Can I set the timer on the connection that Activiti uses? 

Best,
John

Here's my engine file:
  <bean id="processEngineConfiguration" class="org.activiti.engine.impl.cfg.StandaloneProcessEngineConfiguration">
    <property name="history" value="audit" />
    <property name="jdbcUrl" value="jdbc:mysql://localhost:3306/activiti?autoReconnect=true" />
    <property name="jdbcDriver" value="com.mysql.jdbc.Driver" />
    <property name="jdbcUsername" value="trakkit" />
    <property name="jdbcPassword" value="——" />
   
    <property name="databaseSchemaUpdate" value="true" />
   
    <property name="jobExecutorActivate" value="false" />
…   

Here's the exception:

Jun 21, 2013 8:25:45 AM org.activiti.engine.impl.interceptor.CommandContext close
SEVERE: Error while closing command context
org.apache.ibatis.exceptions.PersistenceException:
### Error querying database.  Cause: org.apache.ibatis.transaction.TransactionException: Error configuring AutoCommit.  Your driver may not support getAutoCommit() or setAutoCommit(). Requested setting: false.  Cause: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: The last packet successfu
lly received from the server was39292 seconds ago.The last packet sent successfully to the server was 39292 seconds ago, which  is longer than the server configured value of 'wait_timeout'. You should consider either expiring and/or testing connection validity before use in your application, increasing the server configured values for client timeouts, or using the Connector/J connection property 'autoReconnect=true' to avoid this problem.
### The error may exist in org/activiti/db/mapping/entity/User.xml
### The error may involve org.activiti.engine.impl.persistence.entity.UserEntity.selectUserById
### The error occurred while executing a query
### Cause: org.apache.ibatis.transaction.TransactionException: Error configuring AutoCommit.  Your driver may not support getAutoCommit() or setAutoCommit(). Requested setting: false.  Cause: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: The last packet successfully received from the server was39292 seconds ago.The last packet sent successfully to the server was 39292 seconds ago, which  is longer than the server configured value of 'wait_timeout'. You should consider either expiring and/or testing connection validity before use in your application, increasing the server configured values for client timeouts, or using the Connector/J connection property 'autoReconnect=true' to avoid this problem.
        at org.apache.ibatis.exceptions.ExceptionFactory.wrapException(ExceptionFactory.java:23)
        at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:104)
        at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:95)
        at org.apache.ibatis.session.defaults.DefaultSqlSession.selectOne(DefaultSqlSession.java:59)
        at org.activiti.engine.impl.db.DbSqlSession.selectOne(DbSqlSession.java:307)
        at org.activiti.engine.impl.persistence.entity.UserManager.findUserById(UserManager.java:54)
        at org.activiti.engine.impl.persistence.entity.UserManager.checkPassword(UserManager.java:107)
        at org.activiti.engine.impl.cmd.CheckPassword.execute(CheckPassword.java:37)
        at org.activiti.engine.impl.cmd.CheckPassword.execute(CheckPassword.java:24)
        at org.activiti.engine.impl.interceptor.CommandExecutorImpl.execute(CommandExecutorImpl.java:24)
        at org.activiti.engine.impl.interceptor.CommandContextInterceptor.execute(CommandContextInterceptor.java:60)
        at org.activiti.engine.impl.interceptor.LogInterceptor.execute(LogInterceptor.java:32)
        at org.activiti.engine.impl.IdentityServiceImpl.checkPassword(IdentityServiceImpl.java:90)
        at com.george.bpm.server.TrakkitServiceImpl.validateLogin(TrakkitServiceImpl.java:100)
        at sun.reflect.GeneratedMethodAccessor225.invoke(Unknown Source)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
        at java.lang.reflect.Method.invoke(Unknown Source)
        at com.google.gwt.user.server.rpc.RPC.invokeAndEncodeResponse(RPC.java:561)
        at com.google.gwt.user.server.rpc.RemoteServiceServlet.processCall(RemoteServiceServlet.java:208)
        at com.google.gwt.user.server.rpc.RemoteServiceServlet.processPost(RemoteServiceServlet.java:248)
        at com.google.gwt.user.server.rpc.AbstractRemoteServiceServlet.doPost(AbstractRemoteServiceServlet.java:62)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:647)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
        at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
        at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
        at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99)
        at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:947)
        at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
        at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
        at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1009)
        at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:589)
        at org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.run(AprEndpoint.java:1852)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
        at java.lang.Thread.run(Unknown Source)
Caused by: org.apache.ibatis.transaction.TransactionException: Error configuring AutoCommit.  Your driver may not support getAutoCommit() or setAutoCo
mmit(). Requested setting: false.  Cause: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: The last packet successfully received from the serv
er was39292 seconds ago.The last packet sent successfully to the server was 39292 seconds ago, which  is longer than the server configured value of 'w
ait_timeout'. You should consider either expiring and/or testing connection validity before use in your application, increasing the server configured
values for client timeouts, or using the Connector/J connection property 'autoReconnect=true' to avoid this problem.
        at org.apache.ibatis.transaction.jdbc.JdbcTransaction.setDesiredAutoCommit(JdbcTransaction.java:102)
        at org.apache.ibatis.transaction.jdbc.JdbcTransaction.openConnection(JdbcTransaction.java:135)
        at org.apache.ibatis.transaction.jdbc.JdbcTransaction.getConnection(JdbcTransaction.java:58)
        at org.apache.ibatis.executor.BaseExecutor.getConnection(BaseExecutor.java:279)
        at org.apache.ibatis.executor.SimpleExecutor.prepareStatement(SimpleExecutor.java:69)
        at org.apache.ibatis.executor.SimpleExecutor.doQuery(SimpleExecutor.java:56)
        at org.apache.ibatis.executor.BaseExecutor.queryFromDatabase(BaseExecutor.java:267)
        at org.apache.ibatis.executor.BaseExecutor.query(BaseExecutor.java:141)
        at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:105)
        at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:81)
        at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:101)
        … 37 more

[jbarrez]

When connections get dropped after a certain amount of time, most of the time it is the check for idle connections which needs to be implemented.