Dates
Direct conversions of dates between COM and Java are executed in the native library. These provide faithful translations without getting into the complications of time zones and locales.
COM
Stored internally in GMT as double, as days since Dec 30, 1899, with time-of-day as the fractional part
Java
Stored internally in GMT as 64-bit integer millisecond offsets from the UNIX epoch
Ingres provides the usual PDO methods for checking and setting the Ingres Blank Date and Ingres Date-Without-Time values.