Accessing private fields within a class

Question

I've encountered one interesting thing to me relating to the basics of Java. Here's the code:

class Whoa {
  private int n;

  private void d() {
    Whoa whoa = new Whoa();
    whoa.n = 1;
  }
}

Why the field n of object whoa is accessible? I mean, OK, we're in the class. But whoa is the separate object, I thought we have access only to the fields of a current object. Although I admit that if we have a method that takes a Whoa parameter:

private void b(Whoa w) {
  w.n = 20;
}

we'll definitely have access to n. It's all quite confusing. Could anyone clarify this please?

Yes, the access is on the class level, not on the object level. — Kayaman, Sep 24 '13 at 10:43
I admit it is a little odd that one Whoa can access the private members of **another** Whoa, but that is just the definition of private — Richard Tingle, Sep 24 '13 at 10:43
@Sikorski Thanks, I guess the duplicate is chosen right but in my example the private members are accessed directly by the object reference, not within a public method. — iozee, Sep 24 '13 at 10:52

score 6 · Accepted Answer · answered Sep 24 '13 at 10:43

The point of Java's access modifiers is protecting the internals of a class from code foreign to it. Since all instances of the same class share the same internal code, there would be little use in enforcing access restriction between them.

This the rationale of Java's class-level encapsulation.

score 0 · Answer 2 · answered Sep 24 '13 at 10:43

0

As long as your are in the same class,you can access the private variables

answered Sep 24 '13 at 10:43

SpringLearner

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score 0 · Answer 3 · answered Sep 24 '13 at 10:44

0

For every new instance of the Object 'Whoa' that you create there will be an instance of 'n'. That 'n' can only be accessed from the instance of 'Whoa' (hence private)

answered Sep 24 '13 at 10:44

msam

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Accessing private fields within a class

3 Answers3