通过承当扩大接口[Java编程]

//: HorrorShow.java
// Extending an interface with inheritance

interface Monster {
  void menace();
}

interface DangerousMonster extends Monster {
  void destroy();
}

interface Lethal {
  void kill();
}

class DragonZilla implements DangerousMonster {
  public void menace() {}
  public void destroy() {}
}

interface Vampire 
    extends DangerousMonster, Lethal {
  void drinkBlood();
}

class HorrorShow {
  static void u(Monster b) { b.menace(); }
  static void v(DangerousMonster d) {
    d.menace();
    d.destroy();
  }
  public static void main(String[] args) {
    DragonZilla if2 = new DragonZilla();
    u(if2);
    v(if2);
  }
} ///:~