Is there any reason for public methods in a package protected class?

Question

I wonder if it makes any difference if a method is public or package protected in a class that is package protected.

class Example {
  public void test() {}
}

instead of

class Example {
  void test() {}
}

I guess the maximum visibility is given by the class. And a method can only reduce the visibility and increasing the visibility has no effect.

But it's valid syntax, so perhaps I've overseen something?

Answer 1

If we subclass Example to a public class , then code outside the package can access test() method using the subclass instance if it is public .

Example:

package A;
class Example {
   public void test() {}
}

package A;
public class SubExample extends Example {
}

package B;
import A.SubExample;
class OutsidePackage {
  public void some method(SubExample e){
    // Had test been defined with default access in class Example
    // the below line would be a compilation error.
    e.test();
  }
}

Answer 2

If Example implemented an interface of some kind you'd have to make them public, because you can't reduce access in that case. All interface methods are, by default, public.

Answer 3

As written, it does nothing. If it's a subclass or interface implementation, then it may be implementing or overriding methods that are declared public elsewhere.