if(input.isEmpty()) { return null; }
	public Object[] getElements( List input )	{		Object obj = input.get( 0 );		if ( !( obj instanceof DesignElementHandle ) )			return EMPTY;		ListingHandle element = (ListingHandle) obj;		SlotHandle slot = element.getGroups( );		Iterator iterator = slot.iterator( );		if ( iterator == null )			return EMPTY;		List list = new ArrayList( );		while ( iterator.hasNext( ) )			list.add( iterator.next( ) );		return list.toArray( );	}