当前位置：网站首页>How to List < Map> grouping numerical merge sort

How to List < Map> grouping numerical merge sort

2022-08-09 16:14:00 【Brother doesn't want to work hard】 

import java.util.*;import java.util.stream.Collectors;public class Test {public static void main(String[] args) {//list mock dataMap map1 = new HashMap();map1.put("shopId",1);map1.put("salesmanId",2);map1.put("money", 20);Map map2 = new HashMap();map2.put("shopId",2);map2.put("salesmanId",2);map2.put("money", 100);Map map5 = new HashMap();map5.put("shopId",2);map5.put("salesmanId",2);map5.put("money", 50);List list1 = new ArrayList<>();list1.add(map1);list1.add(map2);list1.add(map5);// System.out.println(list1);// [{salesmanId=2, money=20, shopId=1}, {salesmanId=2, money=100, shopId=2}, {salesmanId=2, money=50, shopId=2}]//list grouping, grouped by supermarketMap> mapGroup = list1.stream().collect(Collectors.groupingBy(o -> o.get("shopId") + ""));// System.out.println(mapGroup);// {1=[{salesmanId=2, money=20, shopId=1}], 2=[{salesmanId=2, money=100, shopId=2}, {salesmanId=2, money=50, shopId=2}]}List listReturn = new ArrayList<>();for (String str : mapGroup.keySet()) {List task1 = mapGroup.get(str);int money = 0;for (Map mm: task1) {money = money + Integer.valueOf(String.valueOf(mm.get("money")));}Map mapReturn = new HashMap();mapReturn.put("shopId", task1.get(0).get("shopId"));mapReturn.put("salesmanId", task1.get(0).get("salesmanId"));mapReturn.put("money", money);listReturn.add(mapReturn);}// System.out.println(listReturn);// [{salesmanId=2, money=20, shopId=1}, {salesmanId=2, money=150, shopId=2}]// sort by money in reverse orderCollections.sort(listReturn, (o2, o1) -> {Integer shop1 = Integer.valueOf(o1.get("shopId").toString());Integer shop2 = Integer.valueOf(o2.get("shopId").toString());return shop1.compareTo(shop2);});// System.out.println(listReturn);// [{salesmanId=2, money=150, shopId=2}, {salesmanId=2, money=20, shopId=1}]}}

原网站

版权声明
本文为[Brother doesn't want to work hard]所创，转载请带上原文链接，感谢
https://yzsam.com/2022/221/202208091450396862.html

边栏推荐

猜你喜欢

随机推荐