java - Target is not a JDK root. System library was not found. Eclipse Oxygen 4.7 + Java9 error

Question

I'm trying to test JDK9 (jdk-9-ea+147 version) with Eclipse Oxygen IDE.

I've installed jdk along with jre. From Eclipse Market Place I've installed Java9 Beta extension:

The problem is, when I'm trying to add new installed jre from Eclipse I get following error:

Interesting thing is that this error doesn't occur with installations of previous JDK versions:

Does anyone encounter simillar problem with Eclipse Oxygen? Any feedback is appreciated.

Answer 1

I've just successfully tested JDK9 with Eclipse Oxygen IDE following the approach you detailed.

Here are the details of my installation (under Windows 10):

• I downloaded and installed Java jdk-9+181 from http://jdk.java.net/9/

• I downloaded and installed Eclipse Oxygen from https://www.eclipse.org/downloads/download.php?file=/oomph/epp/oxygen/R/eclipse-inst-win64.exe

• I started Eclipse and attempted to add JRE9 (Windows -> Preferences -> Java -> Installed JREs -> Add...)

• I got the error reported in the OP ("Target is not a JDK root...").

• I then installed Java 9 Support (BETA) for Oxygen as detailed here: https://marketplace.eclipse.org/content/java-9-support-beta-oxygen

• I restarted Eclipse and tried to add JRE 9 again. This time it worked fine:

• Also, see https://wiki.eclipse.org/Java9/Examples for further details.