I experienced this as well on Xubuntu 20.04 where I had JDK 11 installed. I found this and was able to install JDK 8 and switch to it: https://linuxconfig.org/how-to-install-java-on-ubuntu-20-04-lts-focal-fossa-linux
sbt runs and code compiles now On Monday, November 4, 2019 at 3:03:49 PM UTC-5, Gabe Lafontant wrote: > > I think I _know_ what the source of my issue is but want to ask if anyone > else has seen this problem. Prior to purchasing the book, I had installed > scala on my local machine. My JDK version is 11 and the scala version I > have installed is 2.12.7. I followed the steps in the wiki: > > ``` > $ chmod a+x ./sbt > $ ./sbt > ``` > > When I execute the last command I receive the NullPointerException. I > think this is due to my machine have JDK 11 installed and I should > uninstall it and revert to JDK 8. I think the version of Scala in the book > is not supported by the JDK version I have. My analysis is based on these > findings: > > https://docs.scala-lang.org/overviews/jdk-compatibility/overview.html > https://github.com/ProjectSidewalk/SidewalkWebpage/issues/1346 > > https://stackoverflow.com/questions/32152431/sbt-gives-java-lang-nullpointerexception-when-trying-to-run-simple-hello-exam > > Once I got back to an older version of the JDK I think I should be fine. > Does that make sense? > -- You received this message because you are subscribed to the Google Groups "scala-functional" group. To unsubscribe from this group and stop receiving emails from it, send an email to scala-functional+unsubscr...@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msgid/scala-functional/69bcd325-40ca-4e3f-afce-ea096a9be810%40googlegroups.com.