Eclipse 2018-09 with OpenJDK 11 on Windows 10

Question

I just installed the OpenJDK version of the JDK 11 General-Availability Release on Windows 10. I tried to install it as a JRE in the just-released Eclipse 2018-09 (4.9.0), and a message appared in the Eclipse dialog saying:

You selected a JRE that this version of Eclipse JDT does not yet support fully. Some of the features may not work as expected.

What is the problem?

• Does Eclipse 2018-09 not fully support JDK 11?
• Or is it that Eclipse doesn't fully support OpenJDK 11 but supports the Oracle JDK 11?
• What "features" specifically can I expect to "not work as expected"?

Update: From an Internet search, I found some code that seems to indicate that Eclipse has an internal list of known Java versions, and it gives the above message if the new JDK version has a higher version than the known Java versions. (That's how I interpret the code.) Really? Eclipse launched a new 2018-09 version, just days before JDK 11 was released, without updating its list of known Java versions to include Java 11??

Maybe someone has a more authoritative answer.

Answer 1

Eclipse 2018-09 doesn't support JDK 11 out of the box, but the official plugin for JDK 11 has now been released on the market place:

https://marketplace.eclipse.org/content/java-11-support-eclipse-2018-09-49

Here is the release announcement: https://www.eclipse.org/lists/jdt-dev/msg01049.html

OracleJDK and OpenJDK are supported in the same way (Other JDKs like OpenJ9 should work, too)

If a new JDK release is not supported, you cannot use its new language features and you may not be able to use it all for development because of class format changes. Launching is likely to work.