Iz E-študij, proste zakladnice študentskega znanja
//Mnozica
public interface Set {
public abstract void makenull() ;
public abstract Object first() ;
public abstract Object next(Object pos) ;
public abstract void insert(Object x) ;
public abstract void delete(Object pos) ;
public abstract boolean overEnd(Object pos) ;
public abstract boolean empty() ;
public abstract Object retrieve(Object pos) ;
public abstract Object locate(Object x) ;
public abstract void union(Set a) ;
public abstract void intersection(Set a) ;
public abstract void printSet() ;
}