When Should You Choose Abstract Classes Over Interfaces?

Understanding the Distinction between Abstract Classes and Interfaces

In object-oriented programming, abstract classes and interfaces serve distinct purposes. Let's explore when it's appropriate to use each:

When to Use Interfaces:

Interfaces are ideal for scenarios where you want to enforce a specific contract or behavior without providing an implementation. They declare a set of methods and properties that a class must implement if it implements the interface. This is particularly useful when you need flexibility in runtime interactions and collaboration between different objects.

When to Use Abstract Classes:

Abstract classes, on the other hand, can provide both abstract methods (methods without implementation) and concrete methods (methods with implementation). Classes that extend abstract classes must implement all abstract methods, but they can inherit and use the implementation of concrete methods provided by the abstract class.

Differences and Key Considerations:

• Number of Parent Classes: A class can extend only one parent class (whether abstract or not), but it can implement multiple interfaces.
• Default Implementation: Abstract classes can provide default implementations for methods, while interfaces cannot. This offers more flexibility and code reusability.
• Usage Scenarios: Use interfaces when you want to define a specific contract that other classes must follow. Use abstract classes when you want to extend functionality and provide a partial implementation that other classes can inherit from.

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