Changes in Java 9

Java 9 was releaseed 2017-09-21. It is not an LTS release and was obsoleted at the release of Java 10 on 2018-03-20.

Schedule

2016/05/26		Feature Complete
2016/12/22		Feature Extension Complete
2017/01/05		Rampdown Start
2017/02/09		All Tests Run
2017/02/16		Zero Bug Bounce
2017/03/16		Rampdown Phase Two
2017/06/22		Initial Release Candidate
2017/07/06		Final Release Candidate
2017/09/21		General Availability

Significant Changes from Java 8

• JEP 200: Introduced the modular JDK.
• JEP 243: Java-Level JVM Compiler Interface
  • First prototyped in Java 8, this is the foundation for things like Graal: language compilers written in Java that target the JVM at runtime. It's an experimental feature in Java 9, and the actual API is changed in Java 11.
• Removed javac support for --source/--target 5/1.5.
• Static convenience factory methods for collections, with new immutable implementations.

References about schedule:

• Lesson from JDK Release Milestones (updated on 2019/02/17)