public E removeLRUEntry(){
  if (isEmpty())   return null;
  Iterator<E> i=iterator();
  E value=i.next();
  i.remove();
  return value;
}

public E removeLRUEntry ( ) { if ( isEmpty ( ) ) return null ; Iterator < E > i = iterator ( ) ; E value = i . next ( ) ; i . remove ( ) ; return value ; }
removes the least recently used entry from the set
