Object changes affect data in map

 Public Static void Main (string[] args) {        new person ("Tom", "a");        MapNew hashmap<>();        MapNew hashmap<>();        Map2.put ("M2", p);        Map3.put ("M3", p);        P.setname ("Jerry");        System.out.println (Map2.get ("m2"));        System.out.println (Map3.get ("M3"));    }

As the code above, the class person has two attributes, name and age, and if you change the value of one of the properties after it is placed on the map, the data already stored in the map will be affected.

     Public Static void Main (string[] args) {        = "a";        MapNew hashmap<>();        MapNew hashmap<>();        Map2.put ("M2", p);        Map3.put ("M3", p);         = "ss";        System.out.println (Map2.get ("m2"));        System.out.println (Map3.get ("M3"));    }

But if you put it in a generic object, string or basic type encapsulates the class, it won't be affected.

Need to find a reasonable explanation. Todo

Object changes affect data in map