I've used it on Java 8 projects. The VS Code Java extension reads regular Eclipse projects (.project, .classpath) and offers intellisense like completions, red squiggles etc. But that's basically it. I think there is also support for Mavens poms. What's lacking is the general refactorings, generating boilerplate (hashCode, setters, getters). It's too little for real work but it's surprisingly good so I'll keep evaluating it from time to time.
Microsoft employee here. Thank you for trying! Actually some basic features such as getters, setters, renaming are already supported for Java in VS Code with Red Hat's language server. We'd also like to learn which features are most important for Java developers, please provide feedbacks to us through https://gitter.im/Microsoft/vscode-java-debug or submit https://github.com/Microsoft/vscode-java-debug/issues for whatever you believe is missing.
> Actually some basic features such as getters, setters
Do you mean generating getters and setters based on fields? Because I can't find this option (tried searching for "getter", "java", "generate", no luck) and I've got Red Hat LS installed (alongside the entire Microsoft's Java Extension Pack).
Thanks for you hard work! Language Server Protocol is a hidden gem of VS Code, the most important feature in my opinion.