java util, Collection Interface public add(object elem) public remove(object elem) public boolean containsAll(Collection coll public boolean addAll( Collection coll) public boolean removeAll(Collection coll) public boolean retainAll(Collection col) public void clear public Iterator iteratorjava.util.Collection Interface public add(Object elem) public remove(Object elem) public boolean containsAll(Collection coll) public boolean addAll(Collection coll) public boolean removeAll(Collection coll) public boolean retainAll(Collection coll) public void clear() public Iterator iterator()