Java's Project Valhalla finally lands a preview in JDK 28

JEP 401 for Value Classes and Objects will integrate into OpenJDK mainline targeting JDK 28, adding over 197,000 lines of code. The feature introduces value objects that lack identity, solving long-standing quirks where Integer and LocalDate comparisons behave inconsistently. Architect Brian Goetz warned it will likely remain preview in the next LTS release.