How to implement Singleton Design Pattern in Java using Double Checked Locking Idiom?

To implement the Singleton Design Pattern in Java using Double Checked Locking Idiom, you can follow these steps:

1. Declare a private static volatile instance variable of the class.
2. Create a private constructor for the class to prevent direct instantiation.
3. Create a public static method that returns the instance of the class.
4. Check if the instance variable is null, and if it is, synchronize the code block and check again inside the synchronized block.
5. If the instance variable is still null, create a new instance of the class and assign it to the instance variable.
6. Return the instance variable.

Here's an example implementation of the Singleton Design Pattern in Java using Double Checked Locking Idiom:

"Singleton Design Pattern", "Double Checked Locking Idiom", "Java", "Software Design Patterns", "Object Oriented Programming"

java
public class Singleton {
    private static volatile Singleton instance;
    
    private Singleton() {
        // Private constructor to prevent direct instantiation
    }
    
    public static Singleton getInstance() {
        if (instance == null) {
            synchronized (Singleton.class) {
                if (instance == null) {
                    instance = new Singleton();
                }
            }
        }
        
        return instance;
    }
}