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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<Map<String, Integer>> list = new ArrayList<>(); for (int i = 0; i < 10; i++) { Map<String, Integer> 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<Map<String, Integer>>() { public int compare(Map<String, Integer> m1, Map<String, Integer> 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); }} |
排序前：[{random=79}, {random=44}, {random=38}, {random=65}, {random=43}, {random=83}, {random=90}, {random=87}, {random=83}, {random=13}]
排序后：[{random=13}, {random=38}, {random=43}, {random=44}, {random=65}, {random=79}, {random=83}, {random=83}, {random=87}, {random=90}]