Online Java Compiler

public class ClassicSingleton { private int a = 0; static int b = 0; private static ClassicSingleton instance = null; private ClassicSingleton() { a++; System.out.println("a:"+a); System.out.println("ClassicSingleton() called"); } public static ClassicSingleton getInstance() { b++; System.out.println("b:"+b); instance = new ClassicSingleton(); return instance; } public static void main(String[] args) { ClassicSingleton tmp = ClassicSingleton.getInstance( ); ClassicSingleton tmp2 = ClassicSingleton.getInstance( ); ClassicSingleton tmp3 = ClassicSingleton.getInstance( ); } }