clas for .so println hashmap imp 进行 ret pub
- package test;
- import java.util.ArrayList;
- import java.util.Collections;
- import java.util.Comparator;
- import java.util.HashMap;
- import java.util.List;
- import java.util.Map;
- public class java_ListMapSort {
- public static void main(String[] args) {
- // TODO Auto-generated method stub
- List<Map<String, Object>> list = new ArrayList<Map<String, Object>>();
- Map<String, Object> map1 = new HashMap<String, Object>();
- map1.put("name", "p");
- map1.put("age", "5");
- Map<String, Object> map2 = new HashMap<String, Object>();
- map2.put("name", "h");
- map2.put("age", "12");
- Map<String, Object> map3 = new HashMap<String, Object>();
- map3.put("name", "f");
- map3.put("age", "31");
- list.add(map1);
- list.add(map3);
- list.add(map2);
- //排序前
- for (Map<String, Object> map : list) {
- System.out.println(map.get("age"));
- }
- Collections.sort(list, new Comparator<Map<String, Object>>() {
- public int compare(Map<String, Object> o1, Map<String, Object> o2) {
- Integer age1= Integer.valueOf(o1.get("age").toString()) ;//age1是从你list里面拿出来的第一个 age
- Integer age2= Integer.valueOf(o2.get("age").toString()) ; //age1是从你list里面拿出来的第二个age
- return age1.compareTo(age2); //return age2.compareTo(age1);为降序
- }
- });
- //排序后
- System.out.println("-------------------");
- for (Map<String, Object> map : list) {
- System.out.println(map.get("age"));
- }
- }
- }
JAVA中对list map根据map某个key值进行排序
clas for .so println hashmap imp 进行 ret pub
原文:http://www.cnblogs.com/Dreamice/p/7800905.html
来源: http://www.bubuko.com/infodetail-2384988.html