I know this isn't "the way it's supposed to work", but still: If you have two DateTime objects, what's a good way to subtract them? Convert them to Date objects?
DateTime start = new DateTime();
System.out.println(start + " - doing some stuff");
// do stuff
DateTime end = new DateTime();
Period diff = // end - start ???
System.out.println(end + " - doing some stuff took diff seconds");
Period diff = new Period(start, end);
ReadableInstant is an interface implemented by
DateTime, as well as other classes.)