JDK 21

This release is the Reference Implementation of version 21of the Java SE Platform, as specified byJSR 396 in the Java Community Process.

JDK 21 reachedGeneralAvailability on 19 September 2023. Production-readybinaries under the GPL areavailable from Oracle; binaries fromother vendors will follow shortly.

The features and schedule of this release were proposed andtracked via theJEP Process, as amended by theJEP 2.0proposal. The release was produced using theJDK Release Process (JEP 3).

Features

430:	String Templates (Preview)
431:	Sequenced Collections
439:	Generational ZGC
440:	Record Patterns
441:	Pattern Matching for switch
442:	Foreign Function & Memory API (ThirdPreview)
443:	Unnamed Patterns and Variables(Preview)
444:	Virtual Threads
445:	Unnamed Classes and Instance Main Methods(Preview)
446:	Scoped Values (Preview)
448:	Vector API (Sixth Incubator)
449:	Deprecate the Windows 32-bit x86 Port forRemoval
451:	Prepare to Disallow the Dynamic Loading ofAgents
452:	Key Encapsulation Mechanism API
453:	Structured Concurrency (Preview)

JDK 21 will be a long-term support (LTS) release from mostvendors. For a complete list of the JEPs integrated since theprevious LTS release, JDK 17, please seehere.

Schedule

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