Better build instructions w.r.t Java version

[damienstanton]

The current build doc is confusing, in that it says "Java 8+ should be installed".

Most developers (myself included) will take this to mean that any version 8+ will work, yet Java 11 fails with known issues. This PR corrects the language to make it clear that the user needs Java 8, and no other later version actually works yet.

[fwcd]

Thanks for adding this note.

To provide some background on this: The build instructions were written before we considered Java 11 support in the hope that the project remains compatible with future versions, which apparently was not the case.

[mcraveiro]

Hi, thanks for a great project. I have a question in terms of Java 11 support: is it the case that the language server cannot parse Java 11 projects or just that it cannot be built using Java 11? I ask because I have Java 11 installed and occasionally it seems the language server is working OK, but then it starts spewing a lot of errors whereas command line gradle is happy to compile it.

I've downloaded and installed binaries from the latest release in GitHub.

Thanks for your time.

Marco

[mcraveiro]

Actually, I suspect my problems are not related to the Java version. I've opened a ticket to describe the problem (#126) and I'll move the discussion there. Thanks very much.

[damienstanton]

@mcraveiro I can only speak to the context of my ticket, which had to do with building KLS, not necessarily usage in JDK 11-based Kotlin projects.

[mcraveiro]

Yep, I believe you are spot on @damienstanton - the limitations related to the building of KLS do not appear to be related to the usage in JDK 11-based projects. I am using Java 11 for my projects and I get the same behaviour as when using Java 8.