DRAFT PROPOSAL: Provide date and time library from JSR-310
scolebourne at joda.org
Sun Feb 24 11:21:03 PST 2008
Well, it seems I'll be the first to suggest a JSR derived project for
the challenge. Hopefully the JSR/Challenge combo will be acceptable to
any legal people:
The provision of a date and time library suitable for inclusion in OpenJDK
Two of the least liked APIs of the JDK are those of Date and Calendar.
The classes are mutable when they shouldn't be, have unusual performance
characteristics and months where January is zero.
Having previously tackled this issue via Joda-Time  I am now co-spec
lead of JSR-310 Date and Time API. This JSR is developing, using an open
process a new date and time API targetting the Java 7 release.
2. Goals and deliverables
The goal of this project is to provide a complete working Reference
Implementation of JSR-310 as agreed by the JSR-310 working group .
It should be noted that the JSR is unlikely to be complete within the
timeframe of the challenge. As such, the goal for this project is to
complete the RI as required by the working group. Although a commitment
cannot be made here, it is intended that this should be used to publish
the RI for the JCP Early Draft Review milestone.
JSR-310 and this RI project shall cover as a minimum - immutable classes
for timestamps, dates, times, datetimes, timezone, timezone offset,
alternate calendar systems, duration, period, interval, formatting and
3. Previous work
Work on the RI has already started  and continues to guide the
working group. This project represents the continuation of that development.
The Reference Implementation is BSD licensed. It is not proposed to
change that as it is compatible with the GPL license.
The deliverables are:
1) The source code of the Reference Implementation of JSR-310.
2) The source code of any existing JDK classes modified as part of JSR-310.
3) Source code documentation in the form of javadoc suitable for
inclusion in the JDK.
4) Tests with 90%+ test coverage.
It is expected that the deliverables will correspond to the JCP Early
Draft Review stage.
5. Dependencies on Sun
There are no known dependencies on Sun over and above those Sun has
already agreed to with the JSR-310 working group.
Stephen Colebourne has worked with Java since 1997 and in Open Source
since 2000. He is a Member of the Apache Software Foundation, creator
and project lead of Joda-Time , creator of Kijaro  and co-author
of FCM closures. He is currently a hands-on architect at SITA ATS Ltd
building airline e-commerce systems.
More information about the challenge-discuss