Bug 182895 Support sort on Level attribute.
Currently in OLAP engine we only support sort on level key value. We should go ahead to support sort on level attribute value.
data/org.eclipse.birt.data/src/org/eclipse/birt/data/engine/olap/data/api/CubeQueryExecutorHelper.java
params );
		this.cube = (Cube) cube;
		this.computedMeasureHelper = computedMeasureHelper;
		if (this.computedMeasureHelper != null) 
		{
			validateComputedMeasureNames();
		}
		this.simpleLevelFilters = new ArrayList( );
		this.levelFilters = new ArrayList( );
		this.aggrFilterHelpers = new ArrayList( );
		this.dimJSFilterMap = new HashMap( );
		this.dimRowForFilterMap = new HashMap( );
		
		this.rowSort = new ArrayList( );
		this.columnSort = new ArrayList( );
		
		dimLevelsMap = new HashMap( );
		IDimension[] dimension = this.cube.getDimesions( );
		for ( int i = 0; i < dimension.length; i++ )
		{
			ILevel[] levels = dimension[i].getHierarchy( ).getLevels( );
			dimLevelsMap.put( dimension[i].getName( ), levels );
		}
		logger.exiting( CubeQueryExecutorHelper.class.getName( ),
				"CubeQueryExecutorHelper" );
	}
	
	/**
	 * TODO: get the members according to the specified level.
	 * @param level