Bug 119331 Library - name space terminology and behavior
During BIRT 2.0 library feature review meeting the following change was decided. - Change the term namespace to 'prefix' - By default use the library name as the prefix ( namespace ); the dialog to input prefix should be prompted only if hte auto generated prefix is not unique.
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/internal/ui/dnd/InsertInLayoutUtil.java
{
		private Object container;
		private DataSetItemModel dataSetColumn;
		public GroupKeySetRule( Object container, DataSetItemModel dataSetColumn )
		{
			this.container = container;
			this.dataSetColumn = dataSetColumn;
		}
		/*
		 * (non-Javadoc)
		 * 
		 * @see org.eclipse.birt.report.designer.internal.ui.dnd.InsertInLayoutUtil.InsertInLayoutRule#canInsert()
		 */
		public boolean canInsert( )
		{
			return getGroupContainer( container ) != null
					&& getGroupHandle( container ).getKeyExpr( ) == null
					&& ( getGroupContainer( container ).getDataSet( ) == getDataSetHandle( dataSetColumn ) || getGroupContainer( container ).getDataSet( ) == null );
		}
		/*
		 * (non-Javadoc)
		 * 
		 * @see org.eclipse.birt.report.designer.internal.ui.dnd.InsertInLayoutUtil.InsertInLayoutRule#getInsertPosition()