I am looking for a Java library that handles conversion to/from GPS Time.
GPS Time has an epoch of 6 January 1980, and does not have leap seconds, so it differs from
JSR-310 has classes TAIInstant and UTCInstant which would help solve this problem (as GPS time scale is a variation of TAI). These are located in the ThreeTen-Extra project.
TAIInstant
UTCInstant