Java 9 Download [verified] 64-bit Windows 10 -

Yes. Oracle’s archive is free for development and personal use. For commercial use, check Oracle’s licensing – but since Java 9 is EOL, most organizations avoid it.

java -version

Yes. Use full paths or change JAVA_HOME and PATH when switching. Better yet, use a version manager like jEnv (Linux/macOS) or a batch script for Windows. java 9 download 64-bit windows 10