Which of these is a common real-world analogy used to explain the Decorator Pattern?
Adding toppings to a base coffee or ice cream.
A chain of objects processing a request sequentially.
A factory producing different types of objects.
A tree structure representing hierarchical relationships.
In Python, a common way to implement a Singleton is by using:
Multiple inheritance
Decorators
Interfaces
Abstract classes
In the context of the Decorator Pattern, what is the relationship between the 'ConcreteComponent' and 'Decorator'?
There is no direct relationship between them.
Both the Decorator and ConcreteComponent implement the same interface.
The ConcreteComponent inherits from the Decorator.
The Decorator inherits from the ConcreteComponent.
Which of these is NOT a benefit of using design patterns?
Increased code duplication
Enhanced code maintainability
Facilitated code reuse
Improved code readability
What is a key benefit of using the Strategy Pattern?
Enhanced security by restricting access to algorithms.
Improved code readability and maintainability by separating algorithm logic.
Elimination of conditional statements.
Reduced object creation overhead.
How does the Strategy Pattern promote the Open/Closed Principle?
It prevents modification of existing strategies, ensuring their integrity.
It promotes code reuse by allowing strategies to be shared across multiple contexts.
It allows adding new strategies without modifying the existing Context class.
It reduces the need for inheritance, making the codebase more flexible.
When might the Adapter Pattern be a suitable solution?
When you want to define a template for creating objects.
When you want to decouple your code from a specific third-party library.
When you need to create a new class with similar functionality to an existing one.
When you need to represent a hierarchical relationship between objects.
How does the Decorator Pattern differ from traditional inheritance for extending functionality?
Inheritance allows for dynamic extension at runtime, while Decorator does not.
Decorator modifies the original class, while inheritance creates new subclasses.
Decorator provides more flexibility by allowing the combination of multiple functionalities at runtime.
Inheritance is generally preferred over Decorator due to its simplicity.
What is the primary intent of the Observer pattern?
To define a one-to-many dependency between objects so that when one object changes state, all its dependents are notified and updated automatically.
To provide a way to access the elements of an aggregate object sequentially without exposing its underlying representation.
To ensure a class has only one instance.
To define a family of algorithms, encapsulate each one, and make them interchangeable.
What is the role of an interface in implementing the Observer pattern?
Both B and C
It specifies the methods that concrete observers must implement.
It is not necessary to use interfaces in the Observer pattern.
It defines the methods that the subject uses to notify observers.