I think Animal should be Abstract Class. It's just a blue-print to define actions of animal.
So every Concrete Animal should extend Animal and define their own actions.
I think they must implement their own action because they have their STYLE to walk, sing... They are not same.
Each action in Animal should be return String for easy testing. And return null if they don't have to do that action
A. Let’s start with the basics
1. Can you implement the sing() method for the bird?
a. How did you unit test it?
- Action should be return String or NULL(if animal can't do this action) for easy testing
b. How did you optimize the code for maintainability? - Animal should be abstract class
- Concrete should implement their own action based on Animal blue-print
2. Now, we have 2 special kinds of birds: the Duck and the Chicken... Can you implement them to make their own special sound?
- Animal class has default method swim(). It will return NULL (default animal can't swim)
- Duck can swim. So Duck must Override a swim() method
3. Now how would you model a rooster?
- Rooter has all of Chicken features. And He can Crow. So I will create interface AdultAction with crow() method.
- Rooster can Crow. So we need to implement AdultAction.
4. Can you model a parrot? We are specifically interested in three parrots, one that lived in a house with dogs one in a house with cats, the other lived on a farm next to the rooster.
- Parrot can have friend or not. And His friend is any Animal. So Parrot need to have Animal friend property.
- His friend can or can not says. So we need to check if his friend can not says then he just say by their own language.
B. Model fish as well as other swimming animals
1. In addition to the birds, can you model a fish?
- Fish just extends Animal and implement actions they have.
2. Can you specialize the fish as a Shark and as a Clownfish?
- Shark and Clownfish have characteristics feature. So I will create interface FishFeature and they can implement based on their feature
3. Dolphins are not exactly fish, yet, they are good swimmers
- Dolphin is a mammal and have some fish characteristics. I think he must extends Animal and implement FishFeature.
D. Model animals that change their behaviour over time
1. Can you model a butterfly?
2. Can you optimize your model to account for the metamorphosis from caterpillar to butterfly?
- Caterpillar must extends Animal and Butterfly extend Caterpillar.
- We can see that Butterfly have some feature of Caterpillar and he have some new feature because he's metamorphosis
E. Counting animals
- I see Frog is not defined yet. So I will create a Frog class. He can Walk & Sing.
Animals can fly : 4 , they are : Bird , Duck , Parrot , Butterfly
Animals can walk : 8 , they are : Bird , Duck , Chicken , Rooster , Parrot , Frog , Dog , Cat
Animals can sing : 8 , they are : Bird , Duck , Chicken , Rooster , Parrot , Frog , Dog , Cat
Animals can swim : 5 , they are : Duck , Fish , Shark , Clownfish , Dolphin
BONUS
1. Can you add a second language (if you know a language other than English) Use the
rooster as a PoC for demonstrating this. For example, this is how the Rooster sounds
differently depending on language. Please add the rooster sound in your native
tongue.
- I will add singCms for rooster.
- If we don't pass any param for rooster. He will sing by default language
2. Can you design a RESTFUL API for querying these animals?
- I think we can query these animal by their type.
GET /animal?type=dog
Then we can loop through the List Animal and get an Animal have type DOG