Now that Gradle 4.4.1 is coming to Ubuntu 18.04 LTS, this bug is getting much more relevant as it isn't fixed yet.
Luckily after installing the proposed updates, I was able to revert to Java8 by using
sudo update-java-alternatives -s java-1.8.0-openjdk-amd64
and the WARNING message spamming goes away.
Now that Gradle 4.4.1 is coming to Ubuntu 18.04 LTS, this bug is getting much more relevant as it isn't fixed yet.
Luckily after installing the proposed updates, I was able to revert to Java8 by using
sudo update- java-alternativ es -s java-1. 8.0-openjdk- amd64
and the WARNING message spamming goes away.