Abstract Classes in Java: Explanation & Practice

Problem summary

Create an abstract Shape class with abstract area() method, implemented by Circle.

Starter code

// Create abstract Shape with:
// - abstract double area()

// Create Circle extending Shape:
// - double radius
// - implement area()

public class Main {
    public static void main(String[] args) {
        // Create circle radius 5, print area
    }
}

Expected output and test cases

• Circle area

  Area: 78.54

Hints

1. Abstract methods have no body
2. Abstract class cannot be instantiated
3. Child must implement all abstract methods

Related Inheritance exercises

• Practice Method Overriding in Java
• Practice Using Super Keyword in Java
• Practice Implementing Interface in Java

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