//不建议使用Map保存这些，使用实体bean更好
package com.rxlamo.zhidao;
import java.util.*; public class Main { public static void main(String[] args) { List<Map<String, Object>> list = new ArrayList<>( 4 ); /* * map1:{ID:4，身高:170，体重：60} map2:{ID:4，年龄:20，性别：男} map3:{ID:5，身高:160，体重：50} map4:{ID:5，年龄:19，性别：女} */ Map<String, Object> map1 = new HashMap<>(); map1.put( "ID" , 4 ); map1.put( "身高" , 170 ); map1.put( "体重" , 60 ); list.add(map1); Map<String, Object> map2 = new HashMap<>(); map2.put( "ID" , 4 ); map2.put( "年龄" , 20 ); map2.put( "性别" , '男' ); list.add(map2); Map<String, Object> map3 = new HashMap<>(); map3.put( "ID" , 5 ); map3.put( "身高" , 160 ); map3.put( "体重" , 50 ); list.add(map3); Map<String, Object> map4 = new HashMap<>(); map4.put( "ID" , 5 ); map4.put( "年龄" , 19 ); map4.put( "性别" , '女' ); list.add(map4); merge(list); for ( int i = 0 ; i < list.size(); i++) { Map<String, Object> map = list.get(i); System.out.println(map); } } private static void merge(List<Map<String, Object>> list) { for ( int i = 0 ; i < list.size(); i++) { Map<String, Object> map = list.get(i); // 从当前项的下一项开始检查 for ( int j = i + 1 ; j < list.size(); j++) { Map<String, Object> childMap = list.get(j); // ID 相等 if (map.get( "ID" ).equals(childMap.get( "ID" ))) { // 合并，此处需要先 remove list.remove(childMap); map.putAll(childMap); } } } } }