从(Min,Max)的范围内产生Num个随机数，而且还不能重复的。。（ArrayList，Iterator）

RandomTrial.java

import java.util.ArrayList;
import java.util.Iterator;

public class RandomTrial{
	public static void main(String[] args){
		String [] s = {"one","two","three","four","five","six","seven","eight","nine","ten"};
		ArrayList<Integer> al = new ArrayList<Integer>();
		while(al.size() < 3){
			int num = (int)(Math.random() * 10);
			if (!al.contains(num)) {
				al.add(num);
			}
		}
		Iterator it = al.iterator();
		while(it.hasNext()){
			int i = (int)it.next();
			System.out.print(s[i]+" ");
		}
		/*
		int [] a = new int[3];
		for (int i = 0; i < al.size(); i++) {
			a[i] = al.get(i);
		}
		for (int i : a) {System.out.print(s[i]+" ");
			System.out.print(s[i]+" ");
		}
		 */

	}
}