I always use SimpleDateFormat to print dates so I've never used printf for them. Consider these two pieces of code. Which is easier to read? I think the second is by a landslide. (This is an example from the link you gave - I just made the SimpleDateFormat example.)
As far as the exam, the most common printf flags are on it. The objectives lists which flags you need to know. None of which are date/time flags.
Thanks for responding, I have a basic understading of 't' plus anycombination, however there are many conversions character like the following:
'R' Time formatted for the 24-hour clock as "%tH:%tM"
'T' Time formatted for the 24-hour clock as "%tH:%tM:%tS".
'r' Time formatted for the 12-hour clock as "%tI:%tM:%tS %Tp". The location of the morning or afternoon marker ('%Tp') may be locale-dependent.
'D' Date formatted as "%tm/%td/%ty".
'F' ISO 8601 complete date formatted as "%tY-%tm-%td".
'c' Date and time formatted as "%ta %tb %td %tT %tZ %tY", e.g. "Sun Jul 20 16:17:00 EDT 1969".
which I have not been able to see examples of.
I really hope that they won't be in the exam.. otherwise would be a memery checking test.