On Tue, 5 Aug 2025 01:42:53 GMT, Shaojin Wen <[email protected]> wrote:
> The DateTimeFormatterBuilder::FIELD_MAP previously used a Map<Character, > TemporalField> for mapping pattern characters to TemporalField > instances. This PR refactors that implementation to use a switch expression > instead, which eliminates the need to hold a Map in > memory. > > The switch expression approach offers these advantages: > - No memory overhead for maintaining a HashMap structure > - More direct character-to-field mapping without hash computation > - Better code readability and maintainability > > This change maintains the same functionality while improving the memory > efficiency of pattern character lookup in > DateTimeFormatterBuilder by eliminating the static Map that was previously > used for character-to-field mapping. > > * before > <img width="2018" height="1016" alt="image" > src="https://github.com/user-attachments/assets/57d4c513-55c7-472e-95a8-9f7a4b47662d"; > /> This pull request has now been integrated. Changeset: 2c7f7380 Author: Shaojin Wen <[email protected]> URL: https://git.openjdk.org/jdk/commit/2c7f7380ea828e5ec928e1cb05b13806646ecb3d Stats: 49 lines in 1 file changed: 7 ins; 0 del; 42 mod 8368825: Use switch expression for DateTimeFormatterBuilder pattern character lookup Reviewed-by: rriggs, naoto, scolebourne ------------- PR: https://git.openjdk.org/jdk/pull/26634
