Abstract methods in Typescript - Mini Project: Build & Apply

Using Abstract Methods in TypeScript

📖 Scenario: Imagine you are creating a simple system for different types of vehicles. Each vehicle must have a method to describe how it moves, but the exact way depends on the vehicle type.

🎯 Goal: You will build an abstract class Vehicle with an abstract method move(). Then, you will create two classes Car and Bicycle that extend Vehicle and provide their own move() method.

📋 What You'll Learn

Create an abstract class called Vehicle with an abstract method move() that returns a string.

Create a class called Car that extends Vehicle and implements the move() method returning the string 'The car drives on the road.'.

Create a class called Bicycle that extends Vehicle and implements the move() method returning the string 'The bicycle pedals along the path.'.

Create instances of Car and Bicycle and store them in variables myCar and myBike respectively.

Print the results of calling move() on both myCar and myBike.

💡 Why This Matters

🌍 Real World

Abstract methods are used in software design to define a common interface for different types of objects, like vehicles, animals, or shapes, ensuring they all have certain behaviors.

💼 Career

Understanding abstract classes and methods is important for designing clean, maintainable code in many programming jobs, especially when working with object-oriented languages like TypeScript.

1

Create the abstract class Vehicle with an abstract method move

Create an abstract class called Vehicle with an abstract method move() that returns a string.

Typescript

# Your code here
// Create abstract class Vehicle with abstract method move()

Need a hint?

Use the abstract keyword before the class and the method. The method should have no body.

2

Create classes Car and Bicycle that extend Vehicle and implement move

Create a class called Car that extends Vehicle and implements the move() method returning the string 'The car drives on the road.'. Also create a class called Bicycle that extends Vehicle and implements the move() method returning the string 'The bicycle pedals along the path.'.

Typescript

abstract class Vehicle {
    abstract move(): string;
}

// Your code here
// Create class Car extends Vehicle with move() returning 'The car drives on the road.'
// Create class Bicycle extends Vehicle with move() returning 'The bicycle pedals along the path.'

Need a hint?

Remember to use extends Vehicle and implement the move() method with the exact return strings.

3

Create instances of Car and Bicycle

Create an instance of Car called myCar and an instance of Bicycle called myBike.

Typescript

abstract class Vehicle {
    abstract move(): string;
}

class Car extends Vehicle {
    move(): string {
        return 'The car drives on the road.';
    }
}

class Bicycle extends Vehicle {
    move(): string {
        return 'The bicycle pedals along the path.';
    }
}

// Your code here
// Create myCar as new Car()
// Create myBike as new Bicycle()

Need a hint?

Use const to create the instances with the exact variable names myCar and myBike.

4

Print the results of calling move() on myCar and myBike

Write two console.log statements to print the results of calling move() on myCar and myBike.

Typescript

abstract class Vehicle {
    abstract move(): string;
}

class Car extends Vehicle {
    move(): string {
        return 'The car drives on the road.';
    }
}

class Bicycle extends Vehicle {
    move(): string {
        return 'The bicycle pedals along the path.';
    }
}

const myCar = new Car();
const myBike = new Bicycle();

// Your code here
// Print myCar.move()
// Print myBike.move()

Need a hint?

Use console.log(myCar.move()) and console.log(myBike.move()) to print the messages.