Java List＜Map＜String,Object＞＞集合根据Map里的某个值大小进行排序

约定不等于承诺〃 2022-12-23 11:29 203阅读 0赞

List<Map<String,Object>> 集合根据Map里的某个值大小进行排序

实现代码：

import java.net.SocketException;
    import java.net.UnknownHostException;
    import java.util.*;
    
    public class hhh { 
        public static void main(String[] args) throws UnknownHostException, SocketException { 
    
            List<Map<String, Object>> listResult = new ArrayList<Map<String, Object>>();
            Map<String, Object> map1 = new LinkedHashMap<String, Object>();
            map1.put("sort", 3);
            map1.put("name", "小明");
            map1.put("id", "1");
            listResult.add(map1);
            Map<String, Object> map2 = new LinkedHashMap<String, Object>();
            map2.put("sort", 4);
            map2.put("name", "小李");
            map2.put("id", "2");
            listResult.add(map2);
            Map<String, Object> map3 = new LinkedHashMap<String, Object>();
            map3.put("sort", 1);
            map3.put("name", "小王");
            map3.put("id", "3");
            listResult.add(map3);
            Map<String, Object> map4 = new LinkedHashMap<String, Object>();
            map4.put("sort", 2);
            map4.put("name", "小赵");
            map4.put("id", "4");
            listResult.add(map4);
            System.out.println("排序前：");
            for (Map<String, Object> map : listResult) { 
                System.out.println("sort:" + map.get("sort") + " name:" + map.get("name") + " id:" + map.get("id"));
            }
            Collections.sort(listResult, new MapComparatorDesc());
            System.out.println("根据sort值降序：");
            for (Map<String, Object> map : listResult) { 
                System.out.println("sort:" + map.get("sort") + " name:" + map.get("name") + " id:" + map.get("id"));
            }
            Collections.sort(listResult, new MapComparatorAsc());
            System.out.println("根据sort值升序：");
            for (Map<String, Object> map : listResult) { 
                System.out.println("sort:" + map.get("sort") + " name:" + map.get("name") + " id:" + map.get("id"));
            }
    
        }
    
        /** * 降序 */
        static class MapComparatorDesc implements Comparator<Map<String, Object>> { 
            @Override
            public int compare(Map<String, Object> m1, Map<String, Object> m2) { 
                Integer v1 = Integer.valueOf(m1.get("sort").toString());
                Integer v2 = Integer.valueOf(m2.get("sort").toString());
                if (v2 != null) { 
                    return v2.compareTo(v1);
                }
                return 0;
            }
        }
    
        /** * 升序 */
        static class MapComparatorAsc implements Comparator<Map<String, Object>> { 
            @Override
            public int compare(Map<String, Object> m1, Map<String, Object> m2) { 
                Integer v1 = Integer.valueOf(m1.get("sort").toString());
                Integer v2 = Integer.valueOf(m2.get("sort").toString());
                if (v1 != null) { 
                    return v1.compareTo(v2);
                }
                return 0;
            }
        }
    }

运行结果：  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQwNjE4NjY0_size_16_color_FFFFFF_t_70_pic_center]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQwNjE4NjY0_size_16_color_FFFFFF_t_70_pic_center]: /images/20221120/5d2d6ebf9d5149dc97105a85721a7c9b.png