What\'s the Difference Between `extends` and `implements` in Object-Oriented Programming?

Understanding the Distinction between Implements and Extends in Programming

When developing object-oriented code, developers often encounter the concepts of "implements" and "extends." While these terms may seem similar, they serve distinct purposes in programming. This article aims to clarify the differences between "implements" and "extends."

Extends: Extending a Class

The keyword "extends" is used when a subclass is created that inherits the properties and methods of a superclass. This allows the subclass to access and utilize the functionality defined in the superclass.

Implements: Implementing an Interface

On the other hand, "implements" is used to create a class that conforms to an interface. An interface defines a set of methods that a class must implement. Classes that implement an interface must provide implementations for all the abstract methods declared in the interface.

Key Differences

The fundamental difference between "extends" and "implements" lies in their purpose. "Extends" establishes an inheritance relationship between classes, allowing subclasses to extend the functionality of their superclasses. "Implements," on the other hand, defines a contractual relationship between a class and an interface. The class agrees to provide implementations for the methods declared in the interface.

Conclusion

"Implements" and "extends" are essential concepts in object-oriented programming. "Extends" allows developers to create subclasses that inherit from superclasses, while "implements" ensures that classes conform to the requirements defined by interfaces. Understanding these concepts is crucial for building robust and flexible object-oriented applications.

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