Fix to static final

Comment From: sbrannen

Thanks for the PR.

For this particular use case, converting the field to static won't have any noticeable impact since the referenced field is itself a static singleton.

In addition, we typically do not use all caps for collaborators like the comparator here.

In light of the above, I am closing this PR.

Comment From: hyeonisism

Thank you for sharing your ideas. I learned a lot from this PR.