ashr123 commented on code in PR #3789: URL: https://github.com/apache/logging-log4j2/pull/3789#discussion_r2194921907
########## log4j-core/src/main/java/org/apache/logging/log4j/core/pattern/DatePatternConverter.java: ########## @@ -109,84 +109,11 @@ private static String readPattern(@Nullable final String[] options) { * @since 2.25.0 */ static String decodeNamedPattern(final String pattern) { - - // If legacy formatters are enabled, we need to produce output aimed for `FixedDateFormat` and `FastDateFormat`. - // Otherwise, we need to produce output aimed for `DateTimeFormatter`. - // In conclusion, we need to check if legacy formatters enabled and apply following transformations. - // - // | Microseconds | Nanoseconds | Time-zone - // ------------------------------+--------------+-------------+----------- - // Legacy formatter directive | nnnnnn | nnnnnnnnn | X, XX, XXX - // `DateTimeFormatter` directive | SSSSSS | SSSSSSSSS | x, xx, xxx - // - // Enabling legacy formatters mean that user requests the pattern to be formatted using deprecated - // `FixedDateFormat` and `FastDateFormat`. - // These two have, let's not say _bogus_, but an _interesting_ way of handling certain pattern directives: - // - // - They say they adhere to `SimpleDateFormat` specification, but use `n` directive. - // `n` is neither defined by `SimpleDateFormat`, nor `SimpleDateFormat` supports sub-millisecond precisions. - // `n` is probably manually introduced by Log4j to support sub-millisecond precisions. - // - // - `n` denotes nano-of-second for `DateTimeFormatter`. - // In Java 17, `n` and `N` (nano-of-day) always output nanosecond precision. - // This is independent of how many times they occur consequently. - // Yet legacy formatters use repeated `n` to denote sub-milliseconds precision of certain length. - // This doesn't work for `DateTimeFormatter`, which needs - // - // - `SSSSSS` for 6-digit microsecond precision - // - `SSSSSSSSS` for 9-digit nanosecond precision - // - // - Legacy formatters use `X`, `XX,` and `XXX` to choose between `+00`, `+0000`, or `+00:00`. - // This is the correct behaviour for `SimpleDateFormat`. - // Though `X` in `DateTimeFormatter` produces `Z` for zero-offset. - // To avoid the `Z` output, one needs to use `x` with `DateTimeFormatter`. - final boolean compat = InstantPatternFormatter.LEGACY_FORMATTERS_ENABLED; - - switch (pattern) { - case "ABSOLUTE": - return "HH:mm:ss,SSS"; - case "ABSOLUTE_MICROS": - return "HH:mm:ss," + (compat ? "nnnnnn" : "SSSSSS"); - case "ABSOLUTE_NANOS": - return "HH:mm:ss," + (compat ? "nnnnnnnnn" : "SSSSSSSSS"); - case "ABSOLUTE_PERIOD": - return "HH:mm:ss.SSS"; - case "COMPACT": - return "yyyyMMddHHmmssSSS"; - case "DATE": - return "dd MMM yyyy HH:mm:ss,SSS"; - case "DATE_PERIOD": - return "dd MMM yyyy HH:mm:ss.SSS"; - case "DEFAULT": - return "yyyy-MM-dd HH:mm:ss,SSS"; - case "DEFAULT_MICROS": - return "yyyy-MM-dd HH:mm:ss," + (compat ? "nnnnnn" : "SSSSSS"); - case "DEFAULT_NANOS": - return "yyyy-MM-dd HH:mm:ss," + (compat ? "nnnnnnnnn" : "SSSSSSSSS"); - case "DEFAULT_PERIOD": - return "yyyy-MM-dd HH:mm:ss.SSS"; - case "ISO8601_BASIC": - return "yyyyMMdd'T'HHmmss,SSS"; - case "ISO8601_BASIC_PERIOD": - return "yyyyMMdd'T'HHmmss.SSS"; - case "ISO8601": - return "yyyy-MM-dd'T'HH:mm:ss,SSS"; - case "ISO8601_OFFSET_DATE_TIME_HH": - return "yyyy-MM-dd'T'HH:mm:ss,SSS" + (compat ? "X" : "x"); - case "ISO8601_OFFSET_DATE_TIME_HHMM": - return "yyyy-MM-dd'T'HH:mm:ss,SSS" + (compat ? "XX" : "xx"); - case "ISO8601_OFFSET_DATE_TIME_HHCMM": - return "yyyy-MM-dd'T'HH:mm:ss,SSS" + (compat ? "XXX" : "xxx"); - case "ISO8601_PERIOD": - return "yyyy-MM-dd'T'HH:mm:ss.SSS"; - case "ISO8601_PERIOD_MICROS": - return "yyyy-MM-dd'T'HH:mm:ss." + (compat ? "nnnnnn" : "SSSSSS"); - case "US_MONTH_DAY_YEAR2_TIME": - return "dd/MM/yy HH:mm:ss.SSS"; - case "US_MONTH_DAY_YEAR4_TIME": - return "dd/MM/yyyy HH:mm:ss.SSS"; + try { + return NamedDatePattern.valueOf(pattern).getPattern(); + } catch (IllegalArgumentException ignored) { + return pattern; } Review Comment: @ppkarwasz I agree with you completely, I'll in case of `InstantPatternFormatter.LEGACY_FORMATTERS_ENABLED` is `true`, I'll use `FixedDateFormat.FixedFormat#getPattern`, is that ok? Of course, `NamedInstantPattern` will contain only the non-legacy patterns -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: notifications-unsubscr...@logging.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org