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.
Resources
- JDK 9.0.4 General-Availability Release
- Java Platform, Standard Edition What’s New in Oracle JDK 9
- Java Platform, Standard Edition Oracle JDK 9 Migration Guide
- WTF, Java 9?!
Significant Changes from Java 8
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