*/
public static boolean canRemove(IAbstractDocumentSource source) {
if (isValidSource(source)) {
if (source instanceof IDocumentSource) {
final IDocumentSource layerDocSource = (IDocumentSource) source;
return layerDocSource.canRemove();
} else if (source instanceof IAttachmentSource) {
final IAttachmentSource featureDocSource = (IAttachmentSource) source;
return featureDocSource.canRemove();
} else if (source instanceof IHotlinkSource) {
final IHotlinkSource hotlinkSource = (IHotlinkSource) source;