How can you create a Singleton class in Java?

Question

Accepted Answer

A Singleton class in Java ensures that only one instance of the class is created and provides a global point of access to it.

Use a private static instance variable to hold the single instance of the class.
Make the constructor private to prevent instantiation from outside the class.
Provide a public static method to access the single instance, creating it if necessary.

Accepted Answer

how this Singleton class works:

1. The constructor is made private to prevent other classes from creating instances of Singleton directly.

2. The instance variable is declared as private static, which ensures that there is only one instance of the Singleton class throughout the program's lifetime.

3. The getInstance() method is used to access the single instance of the class. If the instance doesn't exist, it's created the first time this method is called. This is known as lazy initialization.

4. Other methods and fields can be added to the Singleton class as needed.

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