What are the best practices for achieving loose coupling in software design?

What are the best practices for achieving loose coupling in software design?

Loose coupling is a design principle that promotes reducing dependencies between components. Here are some best practices:

1. Use interfaces to define contracts between components.
2. Implement dependency injection to manage dependencies.
3. Favor composition over inheritance.
4. Keep components focused on a single responsibility.
5. Use events or messaging for communication between components.

Can you explain dependency injection?

Dependency injection is a design pattern that allows a class to receive its dependencies from an external source rather than creating them internally. This promotes loose coupling and makes testing easier.

What are some examples of using interfaces?

Interfaces can be used to define a contract for classes. For example, if you have a PaymentProcessor interface, different classes like CreditCardProcessor and PayPalProcessor can implement this interface, allowing you to switch payment methods easily.

How does composition differ from inheritance?

Composition involves building complex types by combining simpler ones, while inheritance creates a new class based on an existing class. Composition is often preferred for loose coupling as it allows for more flexible designs.