Java callback Simple implementation

Package Data;import Java.util.hashmap;import Java.util.map;public class Good {CallBack CallBack;    public void Setcallback (CallBack CallBack) {this.callback=callback;    } private void Domything () {System.out.println ("I do my own thing");        } public void DoSomething () {this.domything ();        System.out.println ("Done my Thing");        System.out.println ("Start callback");    This.callBack.show ();        } public static void Main (string[] args) {good good=new good ();                Good.setcallback (New CallBack () {@Override void ToDo (map<string, string> Map) {                Map.put ("People", "haha");            Map.put ("Age", "100");        }        });    Good.dosomething ();        }}abstract class CallBack {map<string, string> Map = new hashmap<string, string> ();        public void Show () {This.todo (map);        Map.put ("type", "human");    SYSTEM.OUT.PRINTLN (map); } abstract void ToDo (map<string, string> map);} 

Java callback Simple implementation