java生成10个不相等的1-20的随机数

public class Test {
	public static void main(String[] args){
	    Random ran = new Random();
	    Set <Integer> set = new HashSet<Integer>();
	    while(set.size()==10?false:true){
	    	int num = ran.nextInt(20)+1;
	    	set.add(num);
	    }
	    Iterator<Integer> it = set.iterator();
	    int count = 0;
	    while(it.hasNext()){
	    	System.out.println("第"+ ++count +"个随机数 =="+it.next());
	    }
	}
}