Upgrade JDK 8 to JDK 9 and steps to fix your application in Eclipse Oxygen

To install JDK 9 in windows (tested on Windows 10)

1. Download JDK 9 from http://www.oracle.com/technetwork/java/javase/downloads/index.html. Current version when this note created is JDK 9.0.1.
2. Follow installation instruction.
3. In window system environment, set JAVA_HOME to JDK 9
   for example: JAVA_HOME = JAVA_HOME=C:\Java\jdk-9.0.1\
4. In window system environment, set to path to JDK 9 binary folder
   for example Path=...;C:\Java\jdk-9.0.1\bin;...

To Install JDK 9 in Debian Stretch

1. Add Backport repository to /etc/apt/sources.list
   # BACKPORT
   deb http://ftp.de.debian.org/debian stretch-backports main
2. Install JDK 9 straight forward
   # apt-get install openjdk-9-jdk openjdk-9-jdk-headless openjdk-9-jre openjdk-9-jre-headless

Note:

1. You can remove your JDK 8
2. Android Studio 3 and earlier does not work with JDK 9. You may used JDK 8 that bundled in Android Studio 3 (tested on Android Studio 3 in Windows 10).

Your Eclipse Oxygen (version >= 1a) may be find with JDK 9, but you need to migrating your application library from JDK 8 to JDK 9 with these steps (tested on Windows 10):

1. "Package Explorer" right click -> Properties
2. "Java Build Path" -> Library (tab)
3. Remove JRE System Library [JavaSE-1.8]
4. Click "Add Library" botton
5. "Add JRE System Library" -> Next -> "Workspace default JRE (jre-9.0.1)" -> Finish
6. Click Apply botton
7. Click Apply and Close botton 

Reference:

• http://wiki.eclipse.org/Configure_Eclipse_for_Java_9