Interfaces

public interface PetForSale {
  
  /** Display yourself */
  void lookCute();

  /** How much is that doggy in the window? */
  float price();
}

class PetHamster extends Hamster implements PetForSale {

  public Hamster(String name, float weight) {
    super(name, weight);
  }

  void lookCute()
    {
       System.out.println("Hi, I'm " + name + 
                          " the talking hamster!");
       System.out.println("I am " + age + " years old.");
    }

  float price()
    {
       return 50.0 - age*10.0;
    }
}

PetForSale p = new PetHamster("Johnny",1.0);
p.lookCute();

• Interfaces for reusable code
• Multiple interface implementation
• Single class inheritance