编写接口与实现接口，例题

Question

 

Answer 1

package aaa;
 interface person{              //编写接口
  void sayHallo();
  void sayBye();
}
   class Chinese implements person{    //实现接口
   public void sayHallo(){
  System.out.println("你好，见到你很高兴!");
}    
   public void sayBye(){
   System.out.println("再见!");

}

}
   class American implements person{
 public void sayHallo(){
  System.out.println("Hi,nice to meet you!");

}
  public void sayBye(){
 System.out.println("Goodbye!");

}
}
 class InterfaceDemo { 
    public static void main(String[] args) { 
      Chinese c=new  Chinese();
      c.sayHallo();
      c.sayBye();
       American a=new American();
     a.sayHallo();
     a.sayBye();
    }
}