I can access a protected field outside of class in java

Question

Ok so I thought the point of having protected fields was so that the variable was accessible by only the subclass and the class having the protected fields. Making objects of either the subclass or the superclass should not grant access to these fields. If I am correct, how come code like this is compiling correctly?

//superclass
public class SuperClass{
    protected int x = 5;

}

//main class with main method
public class MainClass{        
     public static void main(String[] args) {

         SuperClass a = new SuperClass();

         a.x = 8;       

         System.out.println(a.a);


      }
}

This will print out 8, which means I modified a protected variable outside of the classes which have them...

did you mean System.out.println(a.x); ? – Gonen I Sep 24 '14 at 00:20 — Gonen I, Sep 24 '14 at 00:20

score 3 · Answer 1 · answered Sep 24 '14 at 00:20

protected variables and methods are accessible from other classes of the same package as well as subclasses of the current class.

private variables and method are only accessible from within the current class.

If there is no modifier (none of protected, private or public), then by default the variable is accessible from any classes within the same package but not from subclasses.

see here for the official documentation

SLaks · Answer 2 · 2014-09-24T00:23:19.027

1

protected members in Java are also visible to other classes in the package.

Move your main() method to a different package and you'll get an error.

edited Sep 24 '14 at 00:23

answered Sep 24 '14 at 00:15

SLaks

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(It's a field not a method, but some thing ;)) – MadProgrammer Sep 24 '14 at 00:15

score -2 · Answer 3 · answered Sep 24 '14 at 00:20

I thought the point of having protected fields was so that the variable was accessible by only the subclass and the class having the protected fields.

You thought wrongly.

Making objects of either the subclass or the superclass should not grant access to these fields.

It does. NB You are now contradicting your own thought here. Your thought includes the subclass, and now you're trying to exclude it.

If I am correct

You aren't.

I can access a protected field outside of class in java

3 Answers3