Basic Class Creation

Four independent classes demonstrating basic OOP concepts

Vehicle

Basic class with private attributes and public methods.

• Private properties have getters and setters
• Public methods to control behavior

⚠️ Important: Without proper validation in accelerate() and decelerate() methods, the currentSpeed could:

• Go below zero (if decelerate is called too many times or with large values)
• Exceed maxSpeed (if accelerate is called without checking the limit)

💡 Click to see validation implementation

Good practice: These methods should include validation:

public void accelerate(int speed) {
    currentSpeed += speed;
    if (currentSpeed > maxSpeed) {
        currentSpeed = maxSpeed;  // Cap at maxSpeed
    }
}

public void decelerate(int speed) {
    currentSpeed -= speed;
    if (currentSpeed < 0) {
        currentSpeed = 0;  // Cannot go below 0
    }
}

Computer

Demonstrates encapsulation with memory management.

• Private properties have getters and setters
• Methods to add/remove memory with validation against maxMemory
• Shows how to manage state with constraints

⚠️ Important: Without proper validation in addMemory() and removeMemory() methods, the memory could:

• Go below zero (if removeMemory is called with amount greater than current memory)
• Exceed maxMemory (if addMemory is called without checking the limit)

💡 Click to see validation implementation

Good practice: These methods should include validation:

public void addMemory(int amount) {
    memory += amount;
    if (memory > maxMemory) {
        memory = maxMemory;  // Cap at maxMemory
    }
}

public void removeMemory(int amount) {
    memory -= amount;
    if (memory < 0) {
        memory = 0;  // Cannot go below 0
    }
}

City

Multiple data types (String, double, boolean), constructor and comparison method.

• population: In million
• category:
  • If not a capital: population > 6 = "Big", otherwise: "Small"
  • If capital: population > 7 = "Big", otherwise: "Small"
• Private properties have getters and setters
• Comparison method takes another City object as parameter

Orc

Constructor overloading: 2 constructors with different parameters.

• One constructor with (health, force)
• Another constructor with (name, health, force)
• Private properties have getters and setters
• Method to attack another Orc

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Practice Exercise: Orc Battle

Objective: Create two Orc instances and make them fight in a loop until one is defeated.

Requirements:

1. Instantiate two Orcs with different names, health, and force values
2. Create a loop where they attack each other alternately
3. Display the health of each Orc after each attack
4. Stop when one Orc's health reaches 0 or below
5. Announce the winner

💡 Click to see suggested solution

public class OrcBattle {
    public static void main(String[] args) {
        // Create two orcs
        Orc orc1 = new Orc("Grommash", 100, 15);
        Orc orc2 = new Orc("Thrall", 120, 12);

        System.out.println("=== Battle begins! ===");
        System.out.println(orc1.getName() + " (Health: " + orc1.getHealth() + ", Force: " + orc1.getForce() + ")");
        System.out.println(orc2.getName() + " (Health: " + orc2.getHealth() + ", Force: " + orc2.getForce() + ")");
        System.out.println();

        int round = 1;

        // Battle loop
        while (orc1.getHealth() > 0 && orc2.getHealth() > 0) {
            System.out.println("--- Round " + round + " ---");

            // Orc1 attacks Orc2
            orc1.attack(orc2);
            System.out.println(orc1.getName() + " attacks " + orc2.getName());
            System.out.println(orc2.getName() + " health: " + orc2.getHealth());

            // Check if orc2 is defeated
            if (orc2.getHealth() <= 0) {
                break;
            }

            // Orc2 attacks Orc1
            orc2.attack(orc1);
            System.out.println(orc2.getName() + " attacks " + orc1.getName());
            System.out.println(orc1.getName() + " health: " + orc1.getHealth());

            System.out.println();
            round++;
        }

        // Announce winner
        System.out.println("=== Battle ended! ===");
        if (orc1.getHealth() > 0) {
            System.out.println(orc1.getName() + " wins with " + orc1.getHealth() + " health remaining!");
        } else {
            System.out.println(orc2.getName() + " wins with " + orc2.getHealth() + " health remaining!");
        }
    }
}

Expected Output:

=== Battle begins! ===
Grommash (Health: 100, Force: 15)
Thrall (Health: 120, Force: 12)

--- Round 1 ---
Grommash attacks Thrall
Thrall health: 105
Thrall attacks Grommash
Grommash health: 88

--- Round 2 ---
Grommash attacks Thrall
Thrall health: 90
Thrall attacks Grommash
Grommash health: 76

...

=== Battle ended! ===
Grommash wins with 4 health remaining!

Key Points:

• The attack() method reduces the opponent's health by the attacker's force
• The loop continues while both orcs have health > 0
• We check after each attack if the defender is defeated
• Getters are used to access private properties