Object-Oriented Programming · Question 25 · Medium
Which design pattern ensures that a class has only one instance and provides a global point of access to it?
- Factory Method
- Singleton
- Observer
- Decorator
Answer and explanation
Answer: B. Singleton
Explanation: Singleton uses a private constructor and a static accessor that always returns the same instance. Factory Method creates objects, Observer notifies dependents of changes, and Decorator adds behaviour by wrapping.
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