JDK 21

This release will be the Reference Implementation of version 21 of the Java SE Platform, as specified by JSR 396 in the Java Community Process.


The main-line code repository is open for bug fixes, small enhancements, and JEPs as proposed and tracked via the JEP Process.

Early-access binaries under the GPL are available here.


2023/06/08 Rampdown Phase One (fork from main line)
2023/07/20 Rampdown Phase Two
2023/08/10 Initial Release Candidate
2023/08/24 Final Release Candidate
2023/09/19 General Availability


JEPs targeted to JDK 21, so far
404: Generational Shenandoah (Experimental)
430: String Templates (Preview)
431: Sequenced Collections
439: Generational ZGC
440: Record Patterns
441: Pattern Matching for switch
442: Foreign Function & Memory API (Third Preview)
443: Unnamed Patterns and Variables (Preview)
444: Virtual Threads
445: Unnamed Classes and Instance Main Methods (Preview)
448: Vector API (Sixth Incubator)
449: Deprecate the Windows 32-bit x86 Port for Removal
Last update: 2023/5/19 14:48 UTC