Get Inner Class Instance status

Use case is something similar to below code. There is a class(Inner_Demo) inside another class(Outer_Demo). Inner_class will be instantiated upon some condition in the outer class private method.

class Outer_Demo {

    public Outer_Demo() {
        test();
    }

   // private method of the outer class
   private void test() {
       Inner_Demo demo;
       if(condition)
           demo = new Inner_Demo();
   }

   // inner class
   class Inner_Demo {

   }
}

main(){
    Outer_Demo outer = new Outer_Demo();

    // Here I need to check is Inner class got instantiated
    // Trying to print the value as below leads to error create 
    // field/constant Inner_Demo in Outer_Demo
    System.out.println(Outer_Demo.Inner_Demo); // outer.Inner_Demo

   /* Storing the created instance to Outer_Demo.Inner_Demo 
   is allowed */
   Outer_Demo.Inner_Demo inst = outer.new Inner_Demo();
   System.out.println(inst);
}

I need to test, Is inner class is Instantiated or not. I got to know that calling the inner class in above way is incorrect.

Reflection might have used if the field demo in the Outer_Demo class's method test is not local/ have class level access. Can anybody help me to understand, Is there any way find inner class status. Any links to subject is helpful. Thanks.