Why is subtracting these two times (in 1927) giving a strange result?

Question

If I run the following program, which parses two date strings referencing times 1 second apart and compares them:

public static void main(String[] args) throw         


        

Answer 1

You've encountered a local time discontinuity:

When local standard time was about to reach Sunday, 1. January 1928, 00:00:00 clocks were turned backward 0:05:52 hours to Saturday, 31. December 1927, 23:54:08 local standard time instead

This is not particularly strange and has happened pretty much everywhere at one time or another as timezones were switched or changed due to political or administrative actions.