Java代碼實現按照距離、評分、訂單數排序

從數據查詢出來數據集合後，可能不是我們想要的排序順序，所以需要我們在內存中進行排序

下面是用 Collections.sort()寫的一個例子

import java.util.*;

public class Test {

    public static void main(String[] args) {
        List<Map<String,Object>> list = new ArrayList<>();
        Map<String, Object> map1 = new HashMap<>();
        map1.put("name","港島煲仔飯店");
        map1.put("meter",1000);
        map1.put("grade",50);
        map1.put("count",99);
        list.add(map1);
        Map<String, Object> map2 = new HashMap<>();
        map2.put("name","蘭州拉麪店");
        map2.put("meter",1200);
        map2.put("grade",44);
        map2.put("count",66);
        list.add(map2);
        Map<String, Object> map3 = new HashMap<>();
        map3.put("name","西部大盤雞店");
        map3.put("meter",600);
        map3.put("grade",49);
        map3.put("count",19);
        list.add(map3);

        sort(list,1);
        System.out.println("按距離最近排序");
        for (Map<String,Object> shop : list) {
            System.out.println(shop.get("name")+"---"+"距您"+shop.get("meter")+"米---"+"評分："+Float.valueOf(shop.get("grade").toString())/10+"分---"+"訂單數："+shop.get("count")+"單");
        }
        System.out.println();

        System.out.println("按訂單數最多排序");
        sort(list,2);
        for (Map<String,Object> shop : list) {
            System.out.println(shop.get("name")+"---"+"距您"+shop.get("meter")+"米---"+"評分："+Float.valueOf(shop.get("grade").toString())/10+"分---"+"訂單數："+shop.get("count")+"單");
        }
        System.out.println();

        System.out.println("按評分最高排序");
        sort(list,3);
        for (Map<String,Object> shop : list) {
            System.out.println(shop.get("name")+"---"+"距您"+shop.get("meter")+"米---"+"評分："+Float.valueOf(shop.get("grade").toString())/10+"分---"+"訂單數："+shop.get("count")+"單");
        }

    }

    /**
     * @description: 排序
     * @author: caoju
     */
    public static void sort(List<Map<String,Object>> BusinessList, int type){
        switch (type){
            case 1:
                Collections.sort(BusinessList , (o1, o2)-> {
                    Integer o1Value = Integer.valueOf(o1.get("meter").toString());
                    Integer o2Value = Integer.valueOf(o2.get("meter").toString());
                    return o1Value.compareTo(o2Value);
                });
                break;
            case 2:
                Collections.sort(BusinessList , (o1,o2)-> {
                    Integer o1Value = Integer.valueOf(o1.get("count").toString());
                    Integer o2Value = Integer.valueOf(o2.get("count").toString());
                    return o2Value.compareTo(o1Value);
                });
                break;
            case 3:
                Collections.sort(BusinessList , (o1,o2)-> {
                    Integer o1Value = Integer.valueOf(o1.get("grade").toString());
                    Integer o2Value = Integer.valueOf(o2.get("grade").toString());
                    return o2Value.compareTo(o1Value);
                });
                break;
        }
    }

}

看下最後執行的結果：

可以看到已經按照想排的順序進行排序了