private static String createPostgresTimeZone() {
    String tz = TimeZone.getDefault().getID();
    if (tz.length() <= 3 || !tz.startsWith("GMT")) {
      return tz;
    }
    char sign = tz.charAt(3);
    String start;
    switch (sign) {
      case '+':
        start = "GMT-";
        break;
      case '-':
        start = "GMT+";
        break;
      default:
        // unknown type
        return tz;
    }

    return start + tz.substring(4);
  }
private static String createPostgresTimeZone ( ) { String tz = TimeZone . getDefault ( ) . getID ( ) ; if ( tz . length ( ) <= 3 || ! tz . startsWith ( "GMT" ) ) { return tz ; } char sign = tz . charAt ( 3 ) ; String start ; switch ( sign ) { case '+' : start = "GMT-" ; break ; case '-' : start = "GMT+" ; break ; default : return tz ; } return start + tz . substring ( 4 ) ; }
Convert Java time zone to postgres time zone. All others stay the same except that GMT+nn
changes to GMT-nn and vise versa.

@return The current JVM time zone in postgresql format.