/*
* Searches this {@code TreeSet} for the specified object.
*
* @param object
* the object to search for.
* @return {@code true} if {@code object} is an element of this
* {@code TreeSet}, {@code false} otherwise.
* @throws ClassCastException
* when the object cannot be compared with the elements in this
* {@code TreeSet}.
* @throws NullPointerException
* when the object is null and the comparator cannot handle
* null.
*/
public override bool contains(Object obj)
{
return(backingMap.containsKey(obj));
}