Passing JVM args through sbt

Question

I'm trying to add a 3rd party jar to my java library path. If I invoke sbt with -Djava.library.path=a-3rd-party-lib.jar, then it works for the first invocation of run-main MyClass inside sbt, but thereafter the 3rd party code complains that the jar is not in the java library path. I have also tried adding javaOptions += "-Djava.library.path=a-3rd-party-lib.jar" to my build.sbt file, but this hasn't worked (even for the first run). Qualifying this command as javaOptions in (Test,run) += "-Djava.library.path=a-3rd-party-lib.jar" (as seen in the docs) hasn't worked either.

Am I doing something wrong, or is this a strange bug?

FYI I'm using sbt 0.13.0

Answer 1

javaOptions only takes effect if you fork run and sbt does not fork by default. See the Forking documentation for details, but forking is enabled for run and runMain with:

fork in run := true