public class LinkedList
   { 
     // interface verkettungselement
     public static interface Linkable
     { public Linkable getNext();
       public void setNext(Linkable n);
     }
     
     // kopf der liste:
     Linkable head;
     
     // einfügen:
     public void insert(Linkable n)
     { n.setNext(head);
       head = n;
     }
     // kopfzugriff:
     public Linkable getHead()
     { return head;
     }
   }