Python Design Patterns: Working with Structural Design Patterns

Question : While implementing a decorator, which of the following is true?

A decorator is instantiated with a reference to the object it decorates All decorators implement the same interface

Question : Which of the following best describes the Proxy design pattern?

A placeholder for the real subject to control access to that subject

Question : Which of the following is true in the Façade design pattern?

APIs exposed by the Façade should be simple and easy to use A Façade can have APIs for multiple use cases

Question : If you don't use the decorator pattern to add responsibility dynamically, what might you experience while writing code?

Any new feature will involve major code changes New features added will need to be explicitly combined with all older features while writing code

Question : Which of the following are use cases for the Proxy pattern?

Checking whether client access is authenticated Validating parameters for access to the real subject

Question : Which of the following statement about the Decorator pattern is true?

May involve many objects, each with a different responsibility

Question : Which of the following statements about the Adapter pattern are true?

Presents different views of the object in different contexts Can help newer clients work with legacy components

Question : What is the objective of the flyweight design pattern?

Sharing resources among a large number of lightweight objects

Question : The flyweight design pattern is used in the Python programming language to implement what data type?

Strings

Question : What should you keep in mind when you implement the Facade design pattern?

The Façade should not become the only point of access to the system The Façade should expose a simple interface for complex API calls

Question : Which of the following is true of the Adapter pattern?

Uses a consistent interface across all components

Question : Under what conditions might you choose to implement the Adapter design pattern?

When you want to avoid rewriting your legacy components When you want to present a consistent interface to your clients whether they use new or old compoenents