//The check for duplicate must be done at the URLCheck level
//and not by each specific attribute. Only URLCheck knowns about
//all of the attributes and names.
checkForDuplicate(anAttribute);
//Have each attribute check as much about themself as possible.
anAttribute.check( validProps);
}
}
public void checkForDuplicate(AttributeHolder anAttribute){
Enumeration e = attributes.elements();
while (e.hasMoreElements()) {