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
if ( !(dataSet instanceof IJointDataSetDesign) )
		{
			
			
			String dataSourceName = dataSet.getDataSourceName( );
			DataSourceRuntime dsource = this.getDataSourceRuntime( dataSourceName );
			if ( dsource == null )
			{
				DataException e = new DataException( ResourceConstants.UNDEFINED_DATA_SOURCE,
						dataSourceName );
				logger.logp( Level.WARNING,
						DataEngineImpl.class.getName( ),
						"defineDataSet",
						"Data source {" + dataSourceName + "} is not defined",
						e );
				throw e;
			}
			Class dSourceClass;
			if ( dataSet instanceof IOdaDataSetDesign )
				dSourceClass = IOdaDataSourceDesign.class;
			else if ( dataSet instanceof IScriptDataSetDesign )
				dSourceClass = IScriptDataSourceDesign.class;
			else
			{
				DataException e = new DataException( ResourceConstants.UNSUPPORTED_DATASET_TYPE );
				logger.logp( Level.WARNING,
						DataEngineImpl.class.getName( ),
						"defineDataSet",
						"Unsupported data set type: " + dataSet.getName( ),