package java.util;
public interface Set extends Collection
{
public int size();
public boolean isEmpty();
public boolean contains(Object o);
public Iterator iterator();
public Object[] toArray();
public Object[] toArray(Object[] a);
public boolean add(Object o);
public boolean remove(Object o);
public boolean containsAll(Collection c);
public boolean addAll(Collection c);
public boolean retainAll(Collection c);
public boolean removeAll(Collection c);
public void clear();
public boolean equals(Object o);
public int hashCode();
}