How is a singleton class created?

Question

Accepted Answer

A singleton class ensures a single instance throughout the application, providing a global point of access to that instance.

Private Constructor: The constructor of the singleton class is made private to prevent instantiation from outside the class.
Static Instance: A static variable holds the single instance of the class, ensuring that it is created only once.
Public Method: A public static method (often named getInstance) provides access to the instance, creating it if it doesn't exist.
Thread Safety: To ensure thread safety, synchronization can be used in the getInstance method, or a double-checked locking mechanism can be implemented.
Lazy Initialization: The instance is created only when it is needed, which can save resources if the instance is never used.

Accepted Answer

public class Singleton {
    private static Singleton instance;

private Singleton() {
    }

public static synchronized Singleton getInstance() {
        if (instance == null) {
            instance = new Singleton();
        }
        return instance;
    }
}

How is a singleton class created?

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