Design Pattern—Singleton

public class textSingleton{

public static void main(String[] args) {
Singleton singleton=Singleton.getInstance();
Singleton singleton2=Singleton.getInstance();
Singleton singleton3=Singleton.getInstance();
System.out.println(singleton==singleton2);
System.out.println(singleton2==singleton3);

}
}

class Singleton {

private static Singleton singleton;
private Singleton(){
}

public static Singleton getInstance(){
if(singleton==null){
singleton=new Singleton();
}
return singleton;
}
}