Challenge: Simulate with Objects

You’re building a simple simulation using an object that remembers its state and changes over time.

A Pet class is already set up with:

a name
a hunger level
actions to feed() and play()

Your task

Extend the simulation by adding emotion to your pet.

Add a new instance variable called happiness to Pet.
1. Start it at a reasonable value (for example: 5).
Update the pet’s behavior:
1. When the pet plays, its happiness should increase.
2. When the pet becomes too hungry, its happiness should decrease.
Create a helper method that:
1. Checks the pet’s hunger level
2. Prints a message if the pet is very hungry and unhappy
Update the output in feed() and play() so it shows both hunger and happiness.

Goal

By the end, your pet should:

Remember multiple pieces of state
Change over time based on actions
React differently depending on its condition

Challenge: Simulate with Objects

You’re building a simple simulation using an object that remembers its state and changes over time.

A Pet class is already set up with:

a name
a hunger level
actions to feed() and play()

Your task

Extend the simulation by adding emotion to your pet.

Add a new instance variable called happiness to Pet.
1. Start it at a reasonable value (for example: 5).
Update the pet’s behavior:
1. When the pet plays, its happiness should increase.
2. When the pet becomes too hungry, its happiness should decrease.
Create a helper method that:
1. Checks the pet’s hunger level
2. Prints a message if the pet is very hungry and unhappy
Update the output in feed() and play() so it shows both hunger and happiness.

Goal

By the end, your pet should:

Remember multiple pieces of state
Change over time based on actions
React differently depending on its condition

import java.util.Scanner;

public class Main {
    static class Pet {
        String name;
        int hunger = 5;

        public Pet(String name) {
            this.name = name;
        }

        public void feed() {
            hunger--;
            System.out.println(name + " is fed. Hunger: " + hunger);
        }

        public void play() {
            hunger++;
            System.out.println(name + " played. Hunger: " + hunger);
        }
    }

    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);
        Pet pet = new Pet("Milo");
        int choice = 0;

        while (choice != 3) {
            System.out.println("\n1. Feed\n2. Play\n3. Exit\n> ");
            choice = input.nextInt();

            if (choice == 1) pet.feed();
            else if (choice == 2) pet.play();
        }

        System.out.println("Goodbye!");
        input.close();
    }
}

Project: Simulate with objects