Question

大家好我有一个使用Hibernate检索数据库中数据的Web应用程序。在服务器端，一些例外定期出现。以下是例外日志。

    16:04:22,227 DEBUG NewPooledConnection:491 - com.mchange.v2.c3p0.impl.NewPooledConnection@ef46613 closed by a client.
    java.lang.Exception: DEBUG -- CLOSE BY CLIENT STACK TRACE
        at com.mchange.v2.c3p0.impl.NewPooledConnection.close(NewPooledConnection.java:491)
        at com.mchange.v2.c3p0.impl.NewPooledConnection.close(NewPooledConnection.java:191)
        at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.destroyResource(C3P0PooledConnectionPool.java:470)
        at com.mchange.v2.resourcepool.BasicResourcePool$1DestroyResourceTask.run(BasicResourcePool.java:964)
        at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547)
    16:09:42,310 DEBUG C3P0PooledConnectionPool:476 - Successfully destroyed PooledConnection: com.mchange.v2.c3p0.impl.NewPooledConnection@32ef0763
    16:09:42,310 DEBUG BasicResourcePool:967 - Successfully destroyed resource: com.mchange.v2.c3p0.impl.NewPooledConnection@32ef0763
    16:09:42,310 DEBUG GooGooStatementCache:319 - ENTER METHOD: closeAll( org.postgresql.jdbc4.Jdbc4Connection@42df0af8 )! -- num_connections: 1

有人可以帮我解决这个问题吗？非常感谢！

Answer 1

这是在C3P0中触发此日志语句的代码：

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

请注意：

这也不例外，new Exception仅用于显示执行路径以进行调试。
是的，这只是一条调试消息（实际上，FINEST是java.util.logging中可能的最低级别。）

要将其包装起来：忽略并调整您的日志记录级别以跳过这些。

Answer 2

我发现了错误的位置：我认为当某个对象故意调用时会出现

com.mchange.v2.c3p0.ComboPooledDataSource.close

我在春天配置了这个课程。当我把destroy-method =“close”时出现错误。

显然，我已将其删除，问题现已解决。

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-->
}

奇怪的错误：关闭客户端堆栈跟踪

3 个答案: