Singleton

The Singleton design pattern ensures that only one instance of a class is created and provides a global point of access to it. It is useful in scenarios where there should be a single, shared instance of a class that needs to be accessed globally throughout the application. The Singleton pattern restricts the instantiation of a class to a single object and provides a way to retrieve that instance.

Example in Python:

# Usage

singleton_instance = Singleton.get_instance()

Explanation:

In the above example, the Singleton class ensures that only one instance is created by checking if the instance attribute is None before creating a new instance. The getinstance() method provides the global access point to retrieve the Singleton instance. Once the instance is created, subsequent calls to get_instance() will return the same instance.

Benefits:

• Provides a global access point to a single instance.

• Guarantees that only one instance of the class is created.

• Avoids unnecessary instantiation and reduces memory usage.

Drawbacks:

• Can introduce global state, making it harder to test and maintain.

• Can hinder flexibility and extensibility in some cases.