Bug 136141 Prepared statements not properly cleaned up.
After designing a JDBC query in a report design, I opened the DataSetEditor and choose "Preview Results". There are a number of warnings that came up in the Console indicating there are prepared statements not properly managed or cleaned up. Apr 11, 2006 8:23:04 AM org.eclipse.birt.data.engine.executor.DataSource close WARNING: 1 statements still active. Apr 11, 2006 8:23:05 AM org.eclipse.birt.data.engine.executor.DataSource closeStatement WARNING: statement not found Tracing down the problem a little further, the root cause of the problem is because the DataSourceQuery (in data.engine.executor) is trying to close a dangling reference of a PreparedStatement. The PreparedStatement has been previously dropped from the statementMap of the DataSource when the DataSource.close() was called. But DataSourceQuery is still holding on to a reference of it. The sequence is as follows: 1) DataSourceQuery prepares a statement. This in turn makes DataSource prepare a statement, and creates a PreparedStatement object, adds it to the statementMap. 2) During DataEngineImpl.defineDataSource(), the existing DataSource is closed, replaced by the supplied DataSourceDesign. The DataSource still have statements in its map. And a warning is logged indicating this is a resource leak. It then cleans the statementMap and closes all its open connections. 3) When DataSourceQuery tries to close the dangling statement, it cannot find it. It logs a message "Statement not found". Then, it still proceeds to close it.
data/org.eclipse.birt.data/src/org/eclipse/birt/data/engine/impl/DataEngineImpl.java
DataSetCacheManager.getInstance( )
					.setAlwaysCacheRowCount( context.getCacheCount( ) );
		}
		else if ( cacheOption == DataEngineContext.CACHE_USE_DISABLE )
		{
			DataSetCacheManager.getInstance( )
					.setCacheOption( DataSetCacheManager.DISABLE );
		}
		else if ( appContext != null )
		{
			Object option = appContext.get( DataEngine.DATASET_CACHE_OPTION );
			if ( option != null && option.toString( ).equals( "true" ) )
				DataSetCacheManager.getInstance( )
						.setCacheOption( DataSetCacheManager.DEFAULT );
			else
				DataSetCacheManager.getInstance( )
						.setCacheOption( DataSetCacheManager.DISABLE );
		}
		else
		{
			DataSetCacheManager.getInstance( )
					.setCacheOption( DataSetCacheManager.DISABLE );
		}
	}
	
	/**
	 * Provides a hint to DtE that the consumer is done with the given 
	 * data source connection, and 
	 * that its resources can be safely released as appropriate.
	 * This tells DtE that there is no more ReportQuery