public Binary toBinary() {
    ByteBuffer buf = ByteBuffer.allocate(12);
    buf.order(ByteOrder.LITTLE_ENDIAN);
    buf.putLong(timeOfDayNanos);
    buf.putInt(julianDay);
    buf.flip();
    return Binary.fromByteBuffer(buf);
  }
Provides a wrapper representing a parquet-timestamp, with methods to
convert to and from binary.
ql/src/java/org/apache/hadoop/hive/ql/io/parquet/timestamp/NanoTime.java