On Tue, 14 Oct 2025 23:26:00 GMT, Shaojin Wen <[email protected]> wrote:
> This PR refactors the Double.toHexString method to improve its performance by > eliminating the use of StringBuilder and regex operations. The new > implementation uses a direct byte array approach to construct the hex string > representation, which avoids the overhead of StringBuilder operations and > regex pattern matching. > > Existing tests in `java/lang/Double/ToHexString.java`. src/java.base/share/classes/java/lang/Double.java line 726: > 724: long signifBits = (Double.doubleToLongBits(d) > 725: & DoubleConsts.SIGNIF_BIT_MASK) | > 726: 0x1000000000000000L; As a small syntax improvement, I think using underscores between groups of four digits would help how the count is correct (that syntax was legal when this code was written. Something like 0x1000_0000_0000_0000L ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/27811#discussion_r2443794548
