Interface Realization is a template in a Class Diagram that represents the relationship between a class (or component) and an interface, indicating that the class implements the interface. An interface is a collection of abstract operations (methods or functions) without any implementation details. A class that realizes an interface is contractually obligated to provide an implementation for all the operations defined in the interface.
Interface Realization promotes the concept of separation of concerns by defining the contract (interface) separately from the implementation (class). This allows for greater flexibility and maintainability, as multiple classes can implement the same interface while providing different implementations, and changes to the interface or implementation can be made independently.
Example: In a Class Diagram for a system that processes payments, you might define an interface called “PaymentProcessor” with operations like “authorizePayment()” and “capturePayment()”. Then, you can create different classes such as “CreditCardProcessor” and “PayPalProcessor” that realize the “PaymentProcessor” interface. Each of these classes will have to provide their own implementation of the “authorizePayment()” and “capturePayment()” operations, as defined in the interface. This allows the system to handle various payment methods while maintaining a consistent API for processing payments.