General clean-ups

General clean-ups

Automated refactors:
* use List::sort instead of Collections::sort
* use foreach loops
* use switch statements instead of if/else if constructs
* use contains() instead of comparing indexOf()
* use Collection::removeIf instead of looping explicitly
* use Optional::ifPresent where possible
* use Map::computeIfAbsent instead of conditional puts
* use try with resources

Change-Id: I1f6c2986abb0f151bb4ff1bc262b1c1ae11c523f
Signed-off-by: Stephen Kitt <skitt@redhat.com>