Lesson 11: Module 4 Hands-on Projects

In this final project for Module 4, we will build a fantasy RPG Combat System. This project will require you to use every OOP concept we’ve learned: Classes, Inheritance, Private Attributes, and Polymorphism.

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Project: The "Hero vs. Monster" System

We will build a modular system where different types of characters can battle each other.

1. The Base Class (models/entity.py)

class Entity:
    def __init__(self, name, hp, power):
        self.name = name
        self.__hp = hp # Encapsulated HP
        self.power = power

    def get_hp(self):
        return self.__hp

    def take_damage(self, amount):
        self.__hp -= amount
        print(f"{self.name} took {amount} damage! HP remaining: {self.__hp}")

    def is_alive(self):
        return self.__hp > 0

2. The Hero and Monster Classes

class Hero(Entity):
    def __init__(self, name, hp, power, job):
        super().__init__(name, hp, power)
        self.job = job

    def attack(self, target):
        print(f"{self.name} the {self.job} strikes with {self.power} force!")
        target.take_damage(self.power)

class Monster(Entity):
    def attack(self, target):
        print(f"{self.name} lunges at {target.name}!")
        target.take_damage(self.power)

3. Combat Logic (game.py)

hero = Hero("Aragorn", 100, 20, "Ranger")
enemy = Monster("Orc", 50, 10)

print("--- BATTLE START ---")
while hero.is_alive() and enemy.is_alive():
    hero.attack(enemy)
    if enemy.is_alive():
        enemy.attack(hero)

if hero.is_alive():
    print(f"{hero.name} is victorious!")
else:
    print("Game Over. The monster won.")

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Module 4 Recap: Exercises and Quiz

Exercise 1: Property Additions

Add a level attribute to the Entity class and create a method level_up() that increases hp and power.

Exercise 2: New Subclass

Create a Mage class that inherits from Hero and overrides the attack() method to use magic damage instead of physical power.

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Module 4 Quiz

1. Which concept emphasizes hiding internal data? A) Inheritance B) Polymorphism C) Encapsulation D) Composition

2. Which keyword is used to access a parent class's method? A) parent B) master C) super D) this

3. In the "is-a" vs. "has-a" rule, which corresponds to Composition? A) Is-a B) Has-a

4. True or False: A class method receives self as the first argument.

5. What is "Method Overriding"? A) Calling a method too many times. B) Replacing a parent class's method with a new version in a child class. C) Deleting a method from a class.

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Quiz Answers

1. C | 2. C | 3. B | 4. False (It receives cls) | 5. B

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Conclusion

You’ve mastered Object-Oriented Programming! This is a massive milestone. Most modern applications are built using these exact principles.

In Module 5: File Handling and Error Management, we’ll learn how to save our game data permanently to your computer and how to prevent our programs from crashing!