// Canonical example of top-down (interface) inheritance.

import java.util.ArrayList;
import java.util.Random;

public class SortedArrayList<T extends Comparable<?super T>> extends ArrayList<T> {

    public void insert(int i, T o) {
        this.add(o);
    }

    public boolean add(T o) {
        super.add(o);
        java.util.Collections.sort(this);
        return true;
    }

    public T set(int i, T o) {
        super.set(i, o);
        java.util.Collections.sort(this);
        return o;
    }


    public static void main(String args[]) {
        Random r = new Random();
        ArrayList a = new SortedArrayList();// This is the only place we
                                            // explicitly mention subclass

        for (int i=0; i<10; i++) {
            a.add(r.nextInt(100));
        }
    }

}