List＜Map＞根据map字段排序

从一个list

package yulisao.test;

import org.apache.commons.collections.CollectionUtils;
import org.apache.commons.lang3.StringUtils;

import java.util.*;


public class MapListSort {

    public static void main(String[] args) {
        List> list = initMapList();
        sortByFeild(list, "age", "desc");
        System.out.println("按年纪取最大的一条数据，其姓名是：" + list.get(0).get("name"));

    }

    
    private static List> sortByFeild(List> list, String feild, String sortTyp) {
        if (CollectionUtils.isNotEmpty(list)) {
           list.sort((m1, m2) -> {
                if (StringUtils.equals(sortTyp, "desc")) {
                    return String.valueOf(m2.get(feild)).compareTo(String.valueOf(m1.get(feild)));
                } else {
                    return String.valueOf(m1.get(feild)).compareTo(String.valueOf(m2.get(feild)));
                }
            });
            // 或者 Collections类里面的sort方法也是list.sort()与上面一样
            // Collections.sort(list, (m1, m2)-> String.valueOf(m1.get(feild)).compareTo(String.valueOf(m2.get(feild)))); // lamuda排序
        }

        return list;
    }

    private static List> initMapList() {
        List> lists = new ArrayList<>();

        Map map = new HashMap<>();
        map.put("name", "王五");
        map.put("age", 55);
        map.put("mobile", "15900001112");
        lists.add(map);

        Map map1 = new HashMap<>();
        map1.put("name", "李四");
        map1.put("age", 18);
        map1.put("mobile", "15900001111");
        lists.add(map1);

        Map map2 = new HashMap<>();
        map2.put("name", "赵六");
        map2.put("age", 58);
        map2.put("mobile", "13700001111");
        lists.add(map2);

        return lists;
    }
}

这个排序仍是借助jdk包里面的方法实现，同样的如果list的元素类型是字符串、javabean等等， 修改一下compareTo两边要比较的对象即可