IamLizu

    public static synchronized Singleton getInstance() {
        // checks if instance already created
        if (Instance == null) {
            // if not create an instance
            Instance = new Singleton();
        }
        // return the created instance on all subsequent calls
        return Instance;
    }

IamLizu

public class Singleton {
    // holds created instance of the singleton class
    private static Singleton Instance = new Singleton();
    
    // private constructor
    private Singleton () {}
    
    public static Singleton getInstance() {
        // return the created instance on all subsequent calls
        return Instance;

IamLizu

public class Singleton {

    private volatile static Singleton Instance();
    
    private Singleton () {}
    
    public static Singleton getInstance() {
        if (Instance == null) {
            synchronized (Singleton.class) {
                if (Instance == null) {