java.sql.Timestamp wrong time parsing

Question

Can someone explain why is it so? Why there is a 24 minutes offset for that time and how to deal with it?

Scala 2.12 and Java 8.

scala> java.sql.Timestamp.valueOf("1900-01-01 00:59:00")
res22: java.sql.Timestamp = 1900-01-01 00:59:00.0

scala> java.sql.Timestamp.valueOf("1900-01-01 01:00:00")
res23: java.sql.Timestamp = 1900-01-01 01:24:00.0

scala> java.sql.Timestamp.valueOf("1900-01-01 01:14:00")
res24: java.sql.Timestamp = 1900-01-01 01:38:00.0

scala> java.sql.Timestamp.valueOf("1900-01-01 01:20:00")
res25: java.sql.Timestamp = 1900-01-01 01:44:00.0

scala> java.sql.Timestamp.valueOf("1900-01-01 01:23:00")
res26: java.sql.Timestamp = 1900-01-01 01:47:00.0

scala> java.sql.Timestamp.valueOf("1900-01-01 01:24:00")
res27: java.sql.Timestamp = 1900-01-01 01:24:00.0

scala> java.sql.Timestamp.valueOf("1900-01-01 01:30:00")
res28: java.sql.Timestamp = 1900-01-01 01:30:00.0

Answer 1

Look at the time zone definition in the IANA time zone database:

# Zone  NAME            GMTOFF  RULES   FORMAT  [UNTIL]
Zone    Europe/Warsaw   1:24:00 -       LMT     1880
                        1:24:00 -       WMT     1915 Aug  5 # Warsaw Mean Time
                        1:00    C-Eur   CE%sT   1918 Sep 16  3:00
                        2:00    Poland  EE%sT   1922 Jun
                        1:00    Poland  CE%sT   1940 Jun 23  2:00
                        1:00    C-Eur   CE%sT   1944 Oct
                        1:00    Poland  CE%sT   1977
                        1:00    W-Eur   CE%sT   1988
                        1:00    EU  CE%sT

In 1900, Poland had a time zone offset of one hour and 24 minutes from UTC, i.e., they were using local mean solar time. That was before standard time zones were introduced on August 5, 1915.

It must be that you feed PostgreSQL a timestamp without time zone, which is interpreted at your local time zone (with an offset of 1:24).

Somebody (scala?) then converts this timestamp back to a timestamp in your local time zone, but erroneously uses an offset of one hour.

I don't know how exactly to fix that, but either use timestamp without time zone throughout or fix the component that thinks the Polish time was offset 1 hour from UTC in 1900.