interface SpeakHello {

    void speakHello();

}

class Chinese implements SpeakHello {

   public  void speakHello() {

       System.out.println("中国人习惯问候语：你好,吃饭了吗? ");

   }

}

class English implements SpeakHello {

    public  void speakHello() {

       System.out.println("英国人习惯问候语:你好,天气不错 ");

    }

}

class KindHello {

   public void lookHello(SpeakHello hello) { //接口类型参数

       hello.speakHello();                    //接口回调

   }

}

public class Example6_5 {

   public static void main(String args[]) {

       KindHello kindHello=new KindHello();

       kindHello.lookHello(new Chinese());

       kindHello.lookHello(new English());

   }

}