/ Design Patterns / Creational patterns / Singleton

Singleton Design Pattern in Java

Thread safe Singleton

public final class Singleton {
    private static volatile Singleton instance;

    private Singleton() {}

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

Code examples

Java Singleton in Java Singleton in Java
C++ Singleton in C++: Before and after Singleton in C++
PHP Singleton in PHP
Delphi Singleton in Delphi
Python Singleton in Python