list集合怎么按元素的某一属性排序

import java.util.ArrayList;

import java.util.Collections;

import java.util.Comparator;

import java.util.HashMap;

import java.util.List;

import java.util.Map;

/**

* ClassName: Sort

* @Description: list集合按元素的某一属性排序

* @author ljw

* @date 2018年5月24日

*/

public class Sort {

public static void main(String[] args) {

List> list = new ArrayList<>();

for (int i = 0; i < 10; i++) {

Map map = new HashMap<>();

Integer random = (int)(Math.random() * 100);

map.put("random", random);

list.add(map);

}

//排序前

System.out.println("排序前：" + list);

Collections.sort(list, new Comparator>() {

public int compare(Map m1, Map m2) {

//降序

//return m2.get("random").compareTo(m1.get("random"));

//升序

return m1.get("random").compareTo(m2.get("random"));

}

});

//排序后

System.out.println("排序后：" + list);

}

}