public List validateForAdding(ReportDesign design, DesignElement element, DesignElement toAdd) { if (!containsListingElement(toAdd))
public List validateForAdding( ReportDesign design, DesignElement element, int slotId, DesignElement toAdd ) { if ( !containsListingElement( toAdd ) )
	public List validateForAdding(ReportDesign design, DesignElement element,			DesignElement toAdd) {		if (!containsListingElement(toAdd))			return Collections.EMPTY_LIST;		return doValidate(design, element);	}