Recall & Review
beginner
What is the main purpose of the Observer pattern?
The Observer pattern lets one object (called the subject) notify many other objects (called observers) automatically when its state changes. It helps keep objects updated without tight coupling.
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beginner
How does the Strategy pattern help in software design?
The Strategy pattern allows selecting an algorithm’s behavior at runtime by defining a family of algorithms and making them interchangeable. It helps change how something works without changing the code that uses it.
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beginner
Explain the Command pattern in simple terms.
The Command pattern turns a request or action into an object. This lets you store, queue, or undo actions easily by treating commands as objects.
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intermediate
Which behavioral pattern helps in decoupling the sender of a request from its receiver by using objects to represent actions?
The Command pattern helps decouple the sender and receiver by encapsulating requests as objects, allowing flexible command management like undo, queue, or logging.
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intermediate
Why is the Observer pattern useful in user interface design?
Because it allows UI elements to automatically update when the data they display changes, without the UI needing to constantly check for updates. This keeps the interface responsive and consistent.
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Which pattern allows an object to notify multiple other objects about changes?
✗ Incorrect
The Observer pattern is designed to notify multiple observers when the subject changes.
What does the Strategy pattern primarily help with?
✗ Incorrect
Strategy pattern allows selecting and changing algorithms dynamically.
Which pattern encapsulates a request as an object to support undo operations?
✗ Incorrect
The Command pattern encapsulates requests as objects, enabling undo and other features.
In the Observer pattern, what are the objects that receive updates called?
✗ Incorrect
Observers are the objects that get notified when the subject changes.
Which pattern would you use to switch between different ways of performing a task without changing the task's code?
✗ Incorrect
Strategy pattern allows changing the algorithm or behavior without modifying the client code.
Describe the Observer pattern and give a real-life example where it might be used.
Think about how a news app updates you when new articles arrive.
You got /5 concepts.
Explain how the Command pattern can help implement undo functionality in software.
Consider how a text editor remembers your actions to undo them.
You got /4 concepts.