This archive contains sample Java code implementing the logic underneath the
CPL <time-switch> tag.

The class edu.columbia.cpl.Recurrence implements a recurrence.  It has
all the accessors necessary for setting the parameters of a recurrence.
There are two support classes, edu.columbia.cpl.Duration (which represents a
duration interval) and edu.columbia.cpl.DayAndPosition (which represents
byday rules like "fourth thursday").

This code is only a rudimentary implementation of the CPL time-switch.  It
is missing some error checking, and does not handle the "bysetpos" parameter,
but is otherwise more-or-less complete.

Known bugs with the code are listed in the file 'BUGS'.

The class TestRecur runs through those examples from RFC 2445 which do not
use "bysetpos".  A few tests are adjusted because of obvious errors in RFC
2445. The output of this file (which I believe to be correct) is in the file
test-output.

Written by Jonathan Lennox <lennox@cs.columbia.edu>.  All comments welcome.

This software bears the following copyright notice and license.  (This is
the standard 3-clause BSD license.)


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