How to declare dependency on native .so library for tests?

问题

I have a production application in Akka that I start with the following option:

-Djava.library.path="./native/"

(with native directory containing a library libsigar-amd64-linux.so) and everything is fine.

When I type sbt test I'm facing the following error:

[executorTest-akka.actor.default-dispatcher-13] DEBUG Sigar  - no libsigar-amd64-linux.so in java.library.path
org.hyperic.sigar.SigarException: no libsigar-amd64-linux.so in java.library.path

I tried to modify build.sbt with:

libraryDependencies in Test ++= file("native/libsigar-amd64-linux.so")

but it didn't help.

回答1:

JVM will only load libraries from the java.library.path. The libraryDependencies is for declaring managed dependencies (as e.g. jars).

> help libraryDependencies
Declares managed dependencies.

What you need is to specify the aforementioned java.library.path for your tests. You have two choices.

One you can run tests in a forked JVM, add following lines to your build.sbt

javaOptions in Test += s"""-Djava.library.path=${baseDirectory.value / ".native"}"""

fork in Test := true

Second you can run sbt using (note this will override the java.library.path for the whole process), which in case you're not forking tests, will be visible in tests

sbt -Djava.library.path=./native

回答2:

If you run with forked tests you need to pass the -Djava.library.path to the jvm that runs the tests, you can do that in your sbt-config with something like this:

javaOptions in Test += "-Djava.library.path=\"./native/\"" 

If you do not run with forked tests, the tests is run inside the sbt-jvm and you need to pass -Djava.library.path to that jvm, using the SBT_OPTS environment variable for example.

来源：https://stackoverflow.com/questions/24385458/how-to-declare-dependency-on-native-so-library-for-tests