public class Test3 {
static class Order implements Comparator<Integer> {
@Override
public int compare(Integer o1, Integer o2) {
if (o1 > o2) return -1;
if (o1 < o2) return 1;
return 0;
}
}
public static void main(String[] args) {
TreeSet<Integer> t = new TreeSet<>(new Order());
while (t.size() < 10) {//去除重复元素
Random r = new Random();
t.add(r.nextInt(20) + 1);
}
System.out.println(t);
}
}
输出结果: