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/executor/DataSourceQuery.java
/*
	 * @see org.eclipse.birt.data.engine.odi.IPreparedDSQuery#getParameterValue(int)
	 */
	public Object getOutputParameterValue( int index ) throws DataException
	{
		assert odaStatement != null;
		
		int newIndex = getCorrectParamIndex( index );
		return odaStatement.getParameterValue( newIndex );
	}
	/*
	 * @see org.eclipse.birt.data.engine.odi.IPreparedDSQuery#getParameterValue(java.lang.String)
	 */
	public Object getOutputParameterValue( String name ) throws DataException
	{
		assert odaStatement != null;
				
		checkOutputParamNameValid( name );
		return odaStatement.getParameterValue( name );
	}
    
	/**
	 * In oda layer, it does not differentiate the value retrievation of input
	 * parameter value and ouput parameter value. They will be put in a same
	 * sequence list. However, in odi layer, we need to clearly distinguish them
	 * since only retrieving output parameter is suppored and it should be based
	 * on its own output parameter index. Therefore, this method will do such a
	 * conversion from the output parameter index to the parameter index.
	 * 
	 * @param index based on output parameter order