Weird Error: CLOSE BY CLIENT STACK TRACE

Question

Hi all I have a web application which use Hibernate to retrieve data in the database. And in the server side some execeptions come out at regular interval. Below is the exce

Answer 1

This is the code that triggers this log statement in C3P0:

if ( logger.isLoggable( MLevel.FINEST ) )
  logger.log( MLevel.FINEST, this + " closed by a client.", 
            new Exception("DEBUG -- CLOSE BY CLIENT STACK TRACE") );

Note that:

1. This is not an exception, the new Exception is used merely to show execution path for debug purposes.

2. And yes, this is only a debug message (actually, FINEST is the lowest possible level in java.util.logging).

To wrap this up: ignore and tune your logging levels to skip these.

Answer 2

I found where the error is: I think that it appears when some object calls deliberately

com.mchange.v2.c3p0.ComboPooledDataSource.close

I have configured this class in spring. When I put destroy-method="close" the error appears.

Obviously, I've removed it and the problem is now solved.

Answer 3

Hibernate connection close work like this way so you no need remove the destroy-method="close".

public synchronized void close() throws SQLException
{
  close(null);
}

private void close(Throwable cause) throws SQLException
{
<--statement-->
if(cause == null)
{
 invalidatingException = NORMAL_CLOSE_PLACEHOLDER;
 if(logger.isLoggable(MLevel.FINEST))
 logger.log(MLevel.FINEST, this + " closed by a client.", new Exception("DEBUG -- CLOSE BY CLIENT STACK TRACE"));
<--statement-->
}