Collections工具类

package com.mengge.test;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

public class TestCollections {
	
	public static void main(String[] args) {
		
		List<String> list = new ArrayList<>();
		
		for (int i = 0; i < 10; i++) {
			list.add(String.valueOf(i));
		}
		
		System.out.println(list);
		//[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
		
		//随机排列数组中的元素
		Collections.shuffle(list);

		System.out.println(list);
		//[1, 9, 5, 6, 4, 3, 8, 2, 7, 0]
		
		//反转
		Collections.reverse(list);
		System.out.println(list);
		//[1, 2, 3, 9, 7, 0, 6, 4, 8, 5]

		//重新正向排序
		Collections.sort(list);
		System.out.println(list);
                //[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]



	}
	
	

}


posted on 2019-08-02 18:06  JieFangZhe  阅读(68)  评论(0编辑  收藏  举报

导航