[klodolph]

It sounds like what you really want is a wrapped "instant" class, which contains something more or less equivalent to a Unix timestamp inside it, but prevents you from accidentally interpreting it using the wrong epoch or units. That's what a Postgres timestamp is. Internally, it's a modified Julian date + nanoseconds since midnight UTC, or something like that. But you don't care if you don't work inside the Postgres source.

It is regrettable that APIs make it easy to create datetime objects without timezones, which is why sane people have moved to e.g. Joda Time and the libraries based on it.