Question

Edit: Answered – error was method wasn’t static

I’m used the Singleton Design Pattern

 public class Singleton {
   private static final Singleton INSTANCE = new Singleton();

   // Private constructor prevents instantiation from other classes
   private Singleton() {}

   public static Singleton getInstance() {
      return INSTANCE;
   }
 }

My question is how do I create an object of class Singleton in another class?

I’ve tried:

Singleton singleton = new Singleton(); 
// error - constructor is private
Singleton singleton = Singleton.getInstance();
// error - non-static method cannot be referenced from a static context

What is the correct code?

Thanks,
Spencer

Answer 1

Singleton singleton = Singleton.getInstance();

is the correct way. Make sure your getInstance() method is indeed static.

Since your Singleton implementation is far from being safe – your object can be instantiated via reflection, you may want to create a singleton based on enum