As many of you are aware, Oracle released JDK 9 on 21st September, 2017. According to Oracle, this is the biggest release in Java history after JDK 5 & JDK 8.

JDK 9 has lot of interesting new features that will change the way developers code. I would liketo list of some cool, new features in JDK 9 that every developer should be aware of. This is list This list is an overview. For more detailed information, please review the release notes on the JDK 9 web page.

Behind the Scenes Improvements

These are improvements we can leverage just by moving to JDK 9. We need not to recompile our code in order to move – JDK 8 compiled code can run on JDK 9. These are mostly performance and memory usage improvements.

  1. Store Interned Strings in CDS Archives
  2. Compact Strings
  3. Improve Secure Application Performance
  4. Tiered Attribution for javac
  5. javadoc Search

New Functionalities

These are new tools and capabilities in JDK 9:

  1. Jigsaw -Modularize JDK
  2. Enhanced Deprecation
  3. Convenience factory methods for Collections
  4. Platform Logging API and Service
  5. JShell: Java Shell
  6. Compiler for older platform versions
  7. Multi-release jar files

New Standards support

These standards are already implemented by different technology groups. JDK 9 has support for them.

  1. HTTP 2 Client
  2. Unicode 8.0 support
  3. UTF-8 Property files
  4. HTML 5 Javadoc

Housekeeping Features

These features are for setting up future improvement in JDK and reducing some complexity.

  1. Modular Java Application Packaging
  2. New Version-String Scheme
  3. Make G1 the default Garbage Collector
  4. Validate JVM Command Line Flag arguments
  5. Deprecate the Applet API
  6. Process import statements correctly
  7. Encapsulate Most Internal API
  8. Indify String Concatenation
  9. Filter Incoming Serialization data


Note: These are just some important new features in JDK 9, but there are many more. I encourage everyone here to try all these JDK 9 features by installing JDK 9 in their machine.





Last updated: March 22, 2023