List 進行求和

public class Main {
    public static void main(String[] args) {

        List<Map> lists = new ArrayList<>(10);
        Map<String, Object> m1 = new HashMap<>(16);
        m1.put("age", 1);
        m1.put("name", 1);
        m1.put("sex", 1);
        lists.add(m1);
        Map<String, Object> m2 = new HashMap<>(16);
        m2.put("age", 12);
        m2.put("name", 1);
        m2.put("sex", 13);
        lists.add(m2);

        Map<String, Object> m3 = new HashMap<>(16);
        Set keys = m1.keySet();

        keys.forEach((e) -> {
            lists.forEach((li) -> {
                if (m3.get(e) == null) {
                    m3.put(e.toString(), 0);
                }
                int sum = (Integer) m3.get(e) + (Integer) li.get(e);
                m3.put(e.toString(), sum);
            });

        });

        System.out.println(m3);
        
    }
}

輸出結果

{sex=14, name=2, age=13}