java之Map的使用

public static void main(String[] args) {
        Map<String, String> map = new HashMap<>();
        map.put("name", "mao");
        map.put("name", "mao");
        map.put("gender", "male");
        for (Entry<String, String> entry : map.entrySet()) {
            System.out.println(entry.getKey()+":"+entry.getValue());
        }
    }