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Creating the Sanctuary

There are many Animal s at the Sanctuary.

There is an Attendant at the Sanctuary, whose whose job is to visit each animal and feed it a certain amount of food.

An Animal has * a first Name

An Animal can * eat a numeric amount of food * make noise

There are different types of Animal.

A Herbivore, which does everything an Animal does.

A Carnivore, which can eat another Animal.

Modeling the Application

The description above has several words bolded. They are all nouns.

When you are trying to figure out what classes your program needs, it is often useful to look at the nouns. The nouns often become classes.

Animals

You will create the classes Animal, Herbivore, and Carnivore. Then think of subclasses of each, and create them. An example UML diagram for the Animal hierarchy is shown below.

Animal hierarchy

Functionality
  • When an Animal eats, it makes its noise and displays the amount it ate. This is how we know Animals have eaten.
  • When a Carnivore eats another Animal
  • it says its type and the type of the Animal it ate. (You could also include Animal names here).
    • To get the name of a class, call getClass().getSimpleName() on an object reference.
  • its eat method returns null.

Sanctuary

The Sanctuary is where Animals live. This means the Sanctuary has-a collection of Animals.

The Sanctuary also has-a Attendant.

The SanctuarySimulator coordinates everything, and is executable by a user.

A UML diagram for the class structure is below.

Sanctuary structure

Functionality

When the Sanctuary is created, it only has habitats for Animals (an initialized array).

The SanctuarySimulator adds Animals to the Sanctuary, and creates the Attendant for the Sanctuary.

It then says when the Sanctuary should start the Attendant doing rounds.

When the Attendant does rounds, it will feed each Animal in the array. * If the Animal is-a Herbivore, it should print a message saying it is feeding plants. * If the Animal is-a Carnivore, it should print a message saying it is feeding meat. * The Attendant may feed each Animal a set amount, or this could be based on the type of Animal. For example, if the Animal is-a Elephant or Hippo, it could get a larger amount of food.

The program is finished when the Attendant can do rounds and feed each Animal.

Sample output:

Dum de dum, love taking care of my Animal friends...
Attendant: I will feed this Animal 10 meats...
Lion: ROARRR!
    I ate 10 pounds.
Attendant: I will feed this Animal 10 plants...
Giraffe: I'm tall!
    I ate 10 pounds.
Attendant: I will feed this Animal 40 meats...
Hippo: I like violence!
    I'm hungry hungry, and I ate 40 pounds.
Attendant: I will feed this Animal 40 plants...
Elephant: My trunk has over 40_000 muscles in it.
    I ate 40 pounds.
    That's a lot of food!

Project

Create a new Java Project, AnimalSanctuary.

Implement all of these classes so the Animal Sanctuary runs as described.

When you have this working, challenge yourself with the stretch goals:

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