$ jshell
|  Welcome to JShell -- Version 11
|  For an introduction type: /help intro

jshell> import java.text.SimpleDateFormat

jshell> import java.util.Locale

jshell> SimpleDateFormat uk = new SimpleDateFormat("EEE, dd. MMM. yyyy", Locale.UK)
uk ==> java.text.SimpleDateFormat@babedab4

jshell> SimpleDateFormat de = new SimpleDateFormat("EEE, dd. MMM. yyyy", Locale.GERMANY)
de ==> java.text.SimpleDateFormat@babedab4

jshell> import java.util.TimeZone

jshell> uk.setTimeZone(TimeZone.getTimeZone("GMT"))

jshell> de.setTimeZone(TimeZone.getTimeZone("GMT"))

jshell> import java.util.Date

jshell> Date d = new Date(10000000)
d ==> Thu Jan 01 03:46:40 CET 1970

jshell> uk.format(d)
$10 ==> "Thu, 01. Jan. 1970"

jshell> de.format(d)
$11 ==> "Do., 01. Jan.. 1970"

jshell> SimpleDateFormat us = new SimpleDateFormat("EEE, dd. MMM. yyyy", Locale.US)
us ==> java.text.SimpleDateFormat@babedab4

jshell> us.format(d)
$13 ==> "Thu, 01. Jan. 1970"

jshell> SimpleDateFormat fr = new SimpleDateFormat("EEE, dd. MMM. yyy", Locale.FRANCE)
fr ==> java.text.SimpleDateFormat@ab2f7265

jshell> fr.format(d)
$15 ==> "jeu., 01. janv.. 1970"