Benefits

• Simplification: Facilitates a simplified interface to a complex subsystem, making it easier to understand and use for clients.
• Encapsulation: Hides the complexities of subsystem components behind a single facade class, promoting information hiding and reducing complexity.
• Decoupling: Reduces dependencies between client code and subsystems, promoting loose coupling and enhancing modularity.
• Promotes Reusability: Encapsulating subsystem functionalities in a facade promotes code reuse across different parts of the application.
• Improves Maintainability: Facilitates easier maintenance and updates by centralizing subsystem interactions and reducing the impact of changes.
• Enhances Testing: Simplifies unit testing by providing a single point of interaction that can be easily mocked or stubbed.
• Adaptable to Legacy Systems: Facilitates the integration of legacy systems by providing a modernized and simplified interface.

Structure

The Facade pattern is structured around several key components that work together to simplify interactions with a complex subsystem. Here's a typical structure of the Facade pattern:

• Facade: This is the core of the pattern. It provides a unified interface to a set of interfaces in a subsystem. The facade knows which subsystem classes are responsible for a request and delegates client requests to appropriate subsystem objects.
• Subsystem Classes/Components: These are various classes or interfaces that make up the subsystem. They contain the actual implementation and functionality that the client wants to use but might find complex to interact with directly.
• Client: This is the code that interacts with the Facade to utilize the functionality provided by the subsystem. The client uses the facade's simplified interface without needing to directly interact with the subsystem classes.