Framework
HotSpot is the default Java Virtual Machine implementation, providing JIT compilation, garbage collection, and runtime optimization for the OpenJDK platform.
OpenJDK has moved JEP 544, Ahead-of-Time Code Compilation, to Proposed to Target for JDK 28, with review due to close September 28, 2026. Teams that pay for slow Java startup can pencil it into JDK 28 plans, though sizing the gain will take their own measurements.
Reality
Codename One packed small integer keys into adjacent slots in ParparVM, so a lookup for an absent key walked thousands of entries before finding an empty one. The team swapped in CPython's probe recurrence.
Reality
Oracle's JDK 27 release notes put hybrid post-quantum key exchange for TLS 1.3 into the default configuration. The migration now belongs to whoever schedules the runtime upgrade.
Reality
The feature list is fixed until the September 15 ship date. Five items are previews you have to ask for; two are HotSpot defaults that apply whether you read the notes or not.
Reality
Dan Luu puts the drop in human time per optimization at 1000x and up. The one figure that survived a holdout test in his own experiment was 7 percent.
Reality