Pattern Design Design Pattern 2

Question 1

Which design pattern ensures that adding new product families to a system requires no changes to existing client code?

Accepted Answer

Abstract Factory

Answer

Abstract Factory provides an interface for creating families of related objects, so new families can be introduced without altering client code.

Question 2

In the Decorator pattern, what is the key structural requirement that allows decorators to be stacked?

Accepted Answer

Decorators implement the same interface as the component they wrap

Answer

Decorators implement the same interface as the wrapped component, enabling them to be composed in any order and depth.

Question 3

Which pattern separates an algorithm's skeleton from its specific steps so subclasses can override individual steps?

Accepted Answer

Template Method

Answer

Template Method defines the overall algorithm structure in a base class while deferring specific steps to subclasses.

Question 4

A system needs to convert XML data into JSON format without changing either the XML reader or the JSON writer. Which pattern best applies?

Accepted Answer

Adapter

Answer

The Adapter pattern translates one interface into another, allowing incompatible interfaces like an XML reader and JSON writer to work together.

Question 5

What distinguishes the Flyweight pattern from simple object caching?

Accepted Answer

Flyweight separates intrinsic (shared) state from extrinsic (contextual) state

Answer

Flyweight explicitly splits state into intrinsic shared state (stored in the flyweight) and extrinsic state (passed by the caller) to minimize memory.

Pattern Design Practice Test

Pattern Design Practice Test

Pattern Design Design Pattern 2