how to return dates in java/enumerable convention?

[Jess Balint]

I'm returning string objects from my enumerable, but getting an exception
when trying to use the MONTH function which compiles to:


org.apache.calcite.avatica.util.DateTimeUtils.unixDateExtract(org.apache.calcite.avatica.util.TimeUnitRange.MONTH,
org.apache.calcite.runtime.SqlFunctions.toInt(current[1]))};

current[1] is a string here and an exception is thrown. are dates expected
to be java.util.Date objects? Is there documentation on this?

Thanks.

Jess