When does static inner class get loaded into the JVM memory?

Question

I was playing around some static inner class.

    package com.tutorial; 
    public class MyUpperClass {
        private MyUpperClass () {

        }
        private static class MyStaticInnerClass{
                    private static final MyUpperClass muc = new MyUpperClass ();
        }
        public static MyUpperClass getInstance() {
            return MyStaticInnerClass.muc;
        }
    }

Now, My question is, when does MystaticInnerClass get loaded into the JVM memory?
At the time of, when MyUpperClass get loaded or getInstance() get called?

Comments

When the class gets loaded is just an implementation detail; you want to know when the class is initialized. It will get initialized only when it is first needed, and that is when you call getInstance(). I hope it will clarify the doubt :)