JDK-8160302 addressed a startup regression in java.util.regex.Pattern/CharPredicates by moving eagerly created lambda predicates into methods and switches to only create the lambda expression lazily when used, but the mechanical transformation applied to turn constants into methods/switches is a bit of an eye-sore.

Evaluate cleaner/nicer ways of writing this code in a way that doesn't re-introduce eagerness during startup - or re-evaluate the
change when/if lambda initialization can improve to the point where the eagerness in this case would have negligible startup effect.

[~mcimadamore] suggested: "I believe an enum could do quite well in this particular situation - when we revisit the code in 10, and lead to a more 'declarative' version of the same code. For example, each enum constant could have strings for storing posix/unix predicates, and a method that returns your lazy method reference. That should clean up the code quite a bit."