/**
* Returns a shallow copy of this {@code TreeSet} instance. (The elements themselves are not
* cloned.)
*
* @return a shallow copy of this set
*/
public Object clone() {
TreeSet<E> clone = null;
try {
clone = (TreeSet<E>) super.clone();
} catch (CloneNotSupportedException e) {
throw new InternalError();
}
clone.m = new TreeMap<E, Object>(m);
return clone;
}
