The tools.jar is changed in the Java9 SDK because module system.
Activity
andxu commentedon Apr 25, 2018
Jdt.ls already supports jdk 9/10
testforstephen commentedon May 23, 2018
The issue still exists at debug.core. It's about tools.jar dependency.
testforstephen commentedon May 23, 2018
Closed with PR #178