Feedback from Java - JSR-310

Stephen Colebourne scolebourne at
Tue Mar 16 16:36:47 UTC 2010

I am the spec lead for JSR-310, the project to enhance time handling
in the Java JDK. I'd like to give some feedback/information to this

JSR-310 supports the possiblity of multiple sources of time zone
information. The data here is considered to be the default. I've
referred to this group as "TZDB" (rather than "Olson" as in some
sources). Let me know if you're unhappy with the "TZDB" name.

File format
The format of the time zone data files (zic.8.txt) could do with some
clarifications/simplifications. (ie. can the document be updated?)

Rule - FROM - "The word minimum (or an abbreviation)" should be
changed to "The word minimum or min". Similarly with maximum. At the
moment, the spec is silent about what happens for the letter "m" which
is a valid abbreviation of "minimum" and "maximum". The spec also
allows oddities like "mini".

Rule - TO - "the word only (or an abbreviation)" - please drop the
abbreviation part. Only the full word is used in the data, never the

Rule - IN - "Names the month in which the rule takes effect. Month
names may be abbreviated.". This should specify that the month names
are English. Currently, only the three letter abbreviation is used.
The spec also allows oddities like "Januar" and ambiguities like "J".
Can the spec be limited to just the 3 letter form?

Rule ON - similar comment for day of week. Again the suppiled files
only use the 3 letter abbreviated form. Can the spec be limited to
just the 3 letter form?

I didn't notice any specific comment about case - is the input case sensitive?


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