Just started playing with jdk9 - and kind-of stuck right at the beginning:
I have the same error I find solution from Configure Eclipse for Java 9
Following edit you have to do in eclipse.ini file
And It will solve your problem. Your eclipse.ini file look like following:
--launcher.appendVmargs
-vm
C:\Program Files\Java\jdk-9\bin\javaw.exe
-vmargs
-Dosgi.requiredJavaVersion=1.8
--add-modules=ALL-SYSTEM