访问子类中的私有超类字段

Question

I know that private fields in a superclass are not inherited by the subclass but my assignment requires me to access a private field from a subclass. There is a getter method for it by problem comes from referencing the private variable directly in one of the subclasses methods:

protected void userPicksUp(Player player) {
    System.out.println("What would you like to pick up?");
    Scanner keyboard = new Scanner(System.in);
    String itemToPickUp = keyboard.nextLine();
    if (Utilities.isItemInContainer(itemToPickUp, getRoomObjects())) {
        player.addToInventory(itemToPickUp);
        roomObjects = Utilities.removeFromList(itemToPickUp, getRoomObjects());
    } else {
        System.out.println("That item is not in the room");
    }
}

I can't figure out how to access roomObjects from the superclass for this subclass method. I cannot make any new fields for this assignment. I have also used super() for the subclass' constructor and roomObjects came with that so I don't really understand why I can't access it if it is part of my subclass' constructor?

Answer 1

If I understand correctly, there is a private field in your superclass that you cannot access as it is not available due to inheritance, or even association.

Utilities.isItemInContainer(itemToPickUp, getRoomObjects() I think here, the functionality that requires you to access that private field should not belong in this class, or utility class. It should belong to your superclass where you pass the itemToPickUp. You can indirectly call it from utility class to make it clean.

A private method is so, so the value does not go outside the class, so you need to write methods around it, exposing bits of functionality as per requirement. This is encapsulation. Your data is hidden, a private field for a reason.