Bug 166015 Refactor designer actions to eclipse command framework
Eclipse command framework provide a more explicit way to manage UI actions contributions, we can take it's advantage to make our actions code more clean and maintainable.
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/internal/ui/dnd/InsertInLayoutUtil.java
Object obj = list.get( i );
			if ( obj instanceof ReportElementEditPart )
			{
				Object model = ( (ReportElementEditPart) obj ).getModel( );
				if ( model instanceof ListBandProxy )
				{
					model = ( (ListBandProxy) model ).getSlotHandle( );
				}
				resultList.add( model );
			}
		}
		return new StructuredSelection( resultList );
	}
	private static String getDisplayName( ResultSetColumnHandle column )
	{
		DataSetHandle dataset = (DataSetHandle) column.getElementHandle( );
		for ( Iterator iter = dataset.getPropertyHandle( DataSetHandle.COLUMN_HINTS_PROP )
				.iterator( ); iter.hasNext( ); )
		{
			ColumnHintHandle element = (ColumnHintHandle) iter.next( );
			if ( element.getColumnName( ).equals( column.getColumnName( ) )
					|| column.getColumnName( ).equals( element.getAlias( ) ) )
			{
				return element.getDisplayName( ) == null
						? column.getColumnName( ) : element.getDisplayName( );
			}
		}
		return column.getColumnName( );
	}
}