com.mchange.v2.c3p0.impl.NewPooledConnection@595fa closed by a client. java.lang.Exception: DEBUG -- CLOSE BY CLIENT STACK TRACE

Hello everyone,

I had a problem with my system in production that I do not understand correctly yet.
In the log, I can see the exception = java.lang.Exception: DEBUG – CLOSE BY CLIENT STACK TRACE and during this period my system did not work until I reset the services again.

2018-07-04 09:54:15 DEBUG NewPooledConnection:646 - com.mchange.v2.c3p0.impl.NewPooledConnection@1bfdbc9 closed by a client.
java.lang.Exception: DEBUG -- CLOSE BY CLIENT STACK TRACE
	at com.mchange.v2.c3p0.impl.NewPooledConnection.close(NewPooledConnection.java:646)
	at com.mchange.v2.c3p0.impl.NewPooledConnection.closeMaybeCheckedOut(NewPooledConnection.java:259)
	at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.destroyResource(C3P0PooledConnectionPool.java:619)
	at com.mchange.v2.resourcepool.BasicResourcePool$1DestroyResourceTask.run(BasicResourcePool.java:1024)
	at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:648)
2018-07-04 09:54:15 DEBUG C3P0PooledConnectionPool:627 - Successfully destroyed PooledConnection: com.mchange.v2.c3p0.impl.NewPooledConnection@1bfdbc9
2018-07-04 09:54:15 DEBUG NewPooledConnection:646 - com.mchange.v2.c3p0.impl.NewPooledConnection@595fa closed by a client.
java.lang.Exception: DEBUG -- CLOSE BY CLIENT STACK TRACE
	at com.mchange.v2.c3p0.impl.NewPooledConnection.close(NewPooledConnection.java:646)
	at com.mchange.v2.c3p0.impl.NewPooledConnection.closeMaybeCheckedOut(NewPooledConnection.java:259)
	at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.destroyResource(C3P0PooledConnectionPool.java:619)
	at com.mchange.v2.resourcepool.BasicResourcePool$1DestroyResourceTask.run(BasicResourcePool.java:1024)
	at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:648)
2018-07-04 09:54:15 DEBUG C3P0PooledConnectionPool:627 - Successfully destroyed PooledConnection: com.mchange.v2.c3p0.impl.NewPooledConnection@595fa
2018-07-04 09:54:15 DEBUG BasicResourcePool:1027 - Successfully destroyed resource: com.mchange.v2.c3p0.impl.NewPooledConnection@595fa
2018-07-04 09:54:15 DEBUG BasicResourcePool:1027 - Successfully destroyed resource: com.mchange.v2.c3p0.impl.NewPooledConnection@1bfdbc9
2018-07-04 09:54:15 DEBUG GooGooStatementCache:333 - checkinAll(): com.mchange.v2.c3p0.stmt.GlobalMaxOnlyStatementCache stats -- total size: 0; checked out: 0; num connections: 0; num keys: 0
2018-07-04 09:54:15 DEBUG C3P0PooledConnectionPool:283 - com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager@26515f.acquireResource() returning. 
2018-07-04 09:54:15 DEBUG BasicResourcePool:1747 - trace com.mchange.v2.resourcepool.BasicResourcePool@312e88 [managed: 1, unused: 1, excluded: 0] (e.g. com.mchange.v2.c3p0.impl.NewPooledConnection@595fa)
2018-07-04 09:54:15 DEBUG BasicResourcePool:471 - decremented pending_acquires: 1
2018-07-04 09:54:15 DEBUG BasicResourcePool:1825 - Acquisition series terminated successfully. Decremented pending_acquires [1],  attempts_remaining: 30
2018-07-04 09:54:15 DEBUG GooGooStatementCache:333 - checkinAll(): com.mchange.v2.c3p0.stmt.GlobalMaxOnlyStatementCache stats -- total size: 0; checked out: 0; num connections: 0; num keys: 0
2018-07-04 09:54:15 DEBUG C3P0PooledConnectionPool:283 - com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager@26515f.acquireResource() returning. 
2018-07-04 09:54:15 DEBUG BasicResourcePool:1747 - trace com.mchange.v2.resourcepool.BasicResourcePool@312e88 [managed: 2, unused: 2, excluded: 0] (e.g. com.mchange.v2.c3p0.impl.NewPooledConnection@595fa)
2018-07-04 09:54:15 DEBUG BasicResourcePool:471 - decremented pending_acquires: 0
2018-07-04 09:54:15 DEBUG BasicResourcePool:1825 - Acquisition series terminated successfully. Decremented pending_acquires [0],  attempts_remaining: 30
2018-07-04 09:54:16 DEBUG ThreadPoolAsynchronousRunner:730 - com.mchange.v2.async.ThreadPoolAsynchronousRunner$DeadlockDetector@1a48206 -- Running DeadlockDetector[Exiting. No pending tasks.]
2018-07-04 09:54:26 DEBUG ThreadPoolAsynchronousRunner:730 - com.mchange.v2.async.ThreadPoolAsynchronousRunner$DeadlockDetector@1a48206 -- Running DeadlockDetector[Exiting. No pending tasks.]
2018-07-04 09:54:36 DEBUG ThreadPoolAsynchronousRunner:730 - com.mchange.v2.async.ThreadPoolAsynchronousRunner$DeadlockDetector@1a48206 -- Running DeadlockDetector[Exiting. No pending tasks.]

I’ve read about the issue in others websites and some cases is mentioned that It’s not an error and just it’s necessary modify my log level.

http://forum.spring.io/forum/spring-projects/data/39195-c3po-exception-close-by-client
https://forum.hibernate.org/viewtopic.php?f=1&t=982996

but my doubt is because when the exception has been thrown did not work back and I had that reset the services.

This same problem already with anyone? or anyone knows to solve it?

BR,
Alfonso

This is not a Hibernate issue, so you need to ask this question on the c3p0 forum or communication channel as they know better their framework.