Behavioral Design Patterns Quiz

Q1. What is the primary purpose of the Observer pattern? To encapsulate a request as an object
To allow objects to observe and be notified of changes in other objects
To define a family of algorithms, encapsulate each one, and make them interchangeable
To define the skeleton of an algorithm in a method, deferring some steps to subclasses

Q2. Which behavioral design pattern is used to handle requests by passing them along a chain of handlers? Command
Chain of Responsibility
Mediator
State

Q3. What does the Command pattern allow you to do? Pass requests along a chain of handlers
Encapsulate a request as an object
Define a family of algorithms and make them interchangeable
Alter an object's behavior when its internal state changes

Q4. Which pattern is used to sequentially access the elements of a collection without exposing its underlying representation? Iterator
Observer
Strategy
Visitor

Q5. In the State pattern, what happens when an object's internal state changes? The object's behavior changes as if its class had changed
The object notifies all its observers
The object encapsulates a request as an object
The object passes the request along a chain of handlers

Q6. What is the role of the Mediator pattern in a system? To reduce coupling between objects by having them communicate through a mediator object
To encapsulate a request as an object
To allow objects to observe and be notified of changes in other objects
To define a family of algorithms and make them interchangeable

Q7. Which pattern is used to capture and restore an object's internal state without violating encapsulation? Memento
Command
State
Observer

Q8. When would you use the Strategy pattern instead of the State pattern? When you need to alter an object's behavior when its internal state changes
When you need to define a family of algorithms and make them interchangeable
When you need to handle requests by passing them along a chain of handlers
When you need to allow objects to observe and be notified of changes in other objects

Q9. What is a common use case for the Visitor pattern? To add new operations to existing classes without modifying them
To encapsulate a request as an object
To define the skeleton of an algorithm in a method, deferring some steps to subclasses
To reduce coupling between objects by having them communicate through a mediator object

Q10. Which pattern is particularly useful when you need to perform operations on elements of an object structure without modifying their classes? Visitor
Command
Iterator
Mediator

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