Ubuntu – Unrecognized option: –version Error: Could not create the Java Virtual Machine. Error: A fatal exception has occurred. Program will exit

Ok so sbt had errors since the build file had references to the system environemnt [system.getenv("JAVA_HOME")) in java and in sbt it was scala.sys.env("JAVA_HOME") and similarly to JAVAFX_HOME]

It is common to use JAVA_HOME system variable so this is added in linux by adding the location of java installation to the /etc/environment file. Mine was JAVA_HOME="/usr/lib/jvm/java-8-openjdk-amd64". Remember to not use CLASSPATH in the environment file since it hinder the running of java files.

/etc/environment:

...
JAVA_HOME="/usr/lib/jvm/java-8-openjdk-amd64"
JAVAFX_HOME="/usr/share/java/openjfx"  

Remember to reboot after setting new environment variables.

Also note that update-alternatives should be done both to java and javac. And the

java --version 

does not work since in java 8 it is just

java -version

Also in sbt you can use this line to to add

 unmanagedJars in Compile += Attributed.blank(
   file(System.getenv("JAVA_HOME") + "/jre/lib/jfxrt.jar"))

to set current jfxrt (javaFX) file wherever that is (modify accordingly)