On Mon, 8 Sep 2025 02:27:10 GMT, Shaojin Wen <s...@openjdk.org> wrote:
>> This PR introduces a new efficient API for appending two-digit integers to >> StringBuilders and refactors DateTimeHelper to leverage this new >> functionality. >> >> Changes include: >> >> 1. New `appendPair` method for efficient two-digit integer formatting >> (00-99): >> - Added `AbstractStringBuilder.appendPair(int i)` with core implementation >> - Added `JavaLangAccess.appendPair(StringBuilder, int)` for internal >> access >> - Added `System.JavaLangAccessImpl.appendPair(StringBuilder, int)` bridge >> - Added `DecimalDigits.appendPair(StringBuilder, int)` public static >> utility method >> - Enhanced Javadoc documentation for all new methods >> >> 2. Refactored `DateTimeHelper` to use the new `DecimalDigits.appendPair`: >> - Updated `DateTimeHelper.formatTo` methods for `LocalDate` and >> `LocalTime` >> - Replaced manual formatting logic with the new efficient two-digit >> appending >> - Improved code clarity and consistency in date/time formatting >> >> These changes improve code clarity and performance when formatting two-digit >> numbers, particularly in date/time formatting scenarios. > > Shaojin Wen has updated the pull request with a new target base due to a > merge or a rebase. The pull request now contains six commits: > > - Merge remote-tracking branch 'upstream/master' into appendPair_202508 > > # Conflicts: > # src/java.base/share/classes/jdk/internal/access/JavaLangAccess.java > - Add DecimalDigitsTest to verify appendPair method with LATIN1 and UTF16 > encoding > - Use DecimalDigits.appendPair for formatting in time classes > > This change modifies the toString() methods in MonthDay, YearMonth, > ZoneOffset, and ChronoLocalDateImpl to use DecimalDigits.appendPair for > formatting two-digit numbers. This provides a more efficient and consistent > way to format these values. > > Also added a comment in ChronoLocalDateImpl.toString() to explain why > get() is used instead of getLong() for performance reasons, as the values are > guaranteed to be within the int range for all chronologies. > > Co-authored-by: Qwen-Coder <qwen-co...@alibabacloud.com> > - Optimize year formatting in DateTimeHelper by reducing modulo operation > > Co-authored-by: Qwen-Coder <qwen-co...@alibabacloud.com> > > Refactored the year formatting logic to use subtraction instead of modulo > for calculating the lower two digits, which can be slightly more efficient. > Added a comment to clarify the safety of the input range for > DecimalDigits.appendPair. > - Refactor DateTimeHelper to use DecimalDigits.appendPair for date/time > formatting\n\nThis change updates DateTimeHelper.formatTo methods for > LocalDate and LocalTime\nto use the new DecimalDigits.appendPair method for > formatting month, day, hour,\nminute, and second components. This improves > code clarity and leverages the\nnewly introduced efficient two-digit integer > appending functionality. > > Co-authored-by: Qwen-Coder <qwen-co...@alibabacloud.com> > - Introduce appendPair method for efficient two-digit integer > appending\n\nThis change adds a new internal API to efficiently append > two-digit integers\n(00-99) to a StringBuilder. It includes:\n- > AbstractStringBuilder.appendPair(int i): The core implementation.\n- > JavaLangAccess.appendPair(StringBuilder, int): For internal access.\n- > System.JavaLangAccessImpl.appendPair(StringBuilder, int): Bridge to > AbstractStringBuilder.\n- DecimalDigits.appendPair(StringBuilder, int): > Public static utility method.\n\nImproved Javadoc comments for clarity and > consistency across all new methods. > > Co-authored-by: Qwen-Coder <qwen-co...@alibabacloud.com> If we have string templates in the future, do you think we can replace this with custom string template processors instead to accomplish the same performance (no redundant width checks)? test/jdk/jdk/internal/util/DecimalDigitsTest.java line 33: > 31: /* > 32: * @test > 33: * @bug 0000000 Suggestion: * @bug 8366224 ------------- PR Review: https://git.openjdk.org/jdk/pull/26911#pullrequestreview-3222746717 PR Review Comment: https://git.openjdk.org/jdk/pull/26911#discussion_r2347762729
