java List中相同的数据合并到一起

List<Map<Object,Object>> mapList = new ArrayList<>();
        Map<Object,Object> map = new HashMap<>();
        map.put("C","111");
        map.put("NAME","LB");
        Map<Object,Object> map1 = new HashMap<>();
        map1.put("C","111");
        map1.put("NAME","LA");
        Map<Object,Object> map2 = new HashMap<>();
        map2.put("C","112");
        map2.put("NAME","LC");
        Map<Object,Object> map3 = new HashMap<>();
        map3.put("C","112");
        map3.put("NAME","Lh");
        Map<Object,Object> map4 = new HashMap<>();
        map4.put("C","113");
        map4.put("NAME","LC");
        Map<Object,Object> map5 = new HashMap<>();
        map5.put("C","114");
        map5.put("NAME","LF");
        mapList.add(map);
        mapList.add(map1);
        mapList.add(map2);
        mapList.add(map3);
        mapList.add(map4);
        mapList.add(map5);
        Map<Integer, List<Map<Object,Object>>> mapMap = new HashMap<>();
        for (Map<Object,Object> newMap : mapList){
            List<Map<Object, Object>>  newl = new ArrayList<>();
            // map是否包含此key，若已经包含则添加一个新的数字到对应value集合中
            if (mapMap.containsKey(Integer.valueOf(newMap.get("C").toString()))){
                //mapList.add(Integer.valueOf(newMap.get("C").toString()),newMap);
                mapMap.get(Integer.valueOf(newMap.get("C").toString())).add(newMap);
            }else{
                newl.add(newMap);
                mapMap.put(Integer.valueOf(newMap.get("C").toString()), newl);
            }
        }
        System.out.println(mapMap);

public class Main {
    public static void main(String[] args) {
        List<Integer> list1 = Arrays.asList(1, 2);
        List<Integer> list2 = Arrays.asList(3, 4);
        List<Integer> list3 = Arrays.asList(5, 6);
        List<Integer> integers = mergeList(list1, list2, list3);
        System.out.println(integers);
        List<String> list4 = Arrays.asList("A", "B");
        List<String> list5 = Arrays.asList("C", "D");
        List<String> list6 = Arrays.asList("E", "F");
        List<String> strings = mergeList(list4, list5, list6);
        System.out.println(strings);
    }
    public static <T> List<T> mergeList(List<T>... list){
        List<T> res = new ArrayList<>();
        if (Objects.nonNull(list)) {
            for (List<T> l : list) {
                res.addAll(l);
            }
        }
        return res;
    }
}