There are several issues which deal with border rendering. The first one was JDK-8279614, it dealt with EtchedBorder.

The next one is JDK-8015739. It uses the same approach. Now that two borders are fixed, it is time to refactor the approach to avoid duplicate code.

I propose adding a utility method to SwingUtilities3:

1. Reset the transform;
2. Call the passed interface* to render the unscaled border;
3. Restore the transform.

It will unify border rendering. Other border types will use the utility method.

* The method which renders the border with unscaled Graphics could be a private method in the calling class, method reference could be passed to the utility method.