write a program to create singleton class?

package javaprgms;

public class Singleton {

            static Singleton obj;

            private  Singleton(){

            }

            public static Singleton getInstance(){

                        if(obj!=null){

                                    return  obj;

                        }

                        else{

                                    obj=new Singleton();

                                    return obj;

                        }

            }

            public static void main(String[] args) {

                        Singleton obj=Singleton.getInstance();

                        Singleton obj1=Singleton.getInstance();

                        if(obj==obj1){

                                    System.out.println("indhu");

                        }

                        else{

                                    System.out.println("Sindhu");

                        }

                        System.out.println(obj==obj1);

            }

}

Output:

indhu

true