11. Inheritance 2

Noisy

It takes 0.2 seconds per letter for an animal to make a noise, so “meow” takes 0.8 seconds and “meeeou” is 1.2 seconds. There are two methods to think about:

• public String noise(): the noise that something Noisy makes; and
• public double timeNoise(): the number of seconds it takes to produce that noise.
  

1. Is this best as an interface or an abstract class? Explain your answer.
2. Write the Noisy thing in Java.
3. Make a Dolphin class that makes the “click” noise.

Colorable

A class is Colorable if it has the methods void setColor(int c) and int getColor().

1. Is this best as an interface or an abstract class? Explain your choice.
2. Add the Colorable abilities to your Dolphin.

Cats

A Cat is a Noisy thing that makes one of three noises: “meow”, “purr”, or “rrrrrrr”. When you construct a cat it should get a number 0, 1, or 2 that it uses to choose which noise to make.

A RandomCat is a kind of Cat that makes an unspecified random noise. Each random cat could make a different noise, but a given random cat will always make the same noise.

A VeryRandomCat makes a different random noise every time it makes a noise. Figure out a way to create this class without duplicating code from other classes, possibly by going back to rewrite what you have in a different way.