Java Reflection, creating object of private class from different package

Question

I have a private class (Deque) that I need to create an object of, from another class outside of the package (package com.example)

package com.example;

final class Deque {

    public Deque() {}

}

Using reflection, how would I go about creating an object of Type com.example.Deque, from a class that is not inside the package com.example?

Answer 1

It is tricky and usually not recommended to do so, but you can create and object of Deque outside the package. I am not aware if you can have a proper reference of the type Deque to it though.

package com.demo;

final class NotADeque {

    public NotADeque() {}

    public static void main(String[] args) throws ClassNotFoundException, 
        NoSuchMethodException, IllegalAccessException, InvocationTargetException, 
        InstantiationException {
      Class<?> c = Class.forName("com.example.Deque");
      Constructor<?> constructor = c.getDeclaredConstructor();
      constructor.setAccessible(true);//Make the constructor accessible.

      Object o = constructor.newInstance();
      System.out.println(o);
    }
}

This will create an instance of Deque, but with an Object reference to it. Also look at the amount of checked exceptions that might be thrown while doing this, this is a very flimsy approach. For more details check this question