java.lang.NoClassDefFoundError: scala/reflect/api/TypeCreator

Question

I'm getting this error message when I run my sbt project in IntelliJ by right clicking "Debug".

/home/johnreed/Applications/jdk1.8.0_73/bin/java -agentlib:jdwp=transport=dt_socket,address=127.0.0.1:34395,suspend=y,server=n -Dfile.encoding=UTF-8 -classpath /home/johnreed/Applications/jdk1.8.0_73/jre/lib/charsets.jar:/home/johnreed/Applications/jdk1.8.0_73/jre/lib/deploy.jar:/home/johnreed/Applications/jdk1.8.0_73/jre/lib/ext/cldrdata.jar:/home/johnreed/Applications/jdk1.8.0_73/jre/lib/ext/dnsns.jar:/home/johnreed/Applications/jdk1.8.0_73/jre/lib/ext/jaccess.jar:/home/johnreed/Applications/jdk1.8.0_73/jre/lib/ext/jfxrt.jar:/home/johnreed/Applications/jdk1.8.0_73/jre/lib/ext/localedata.jar:/home/johnreed/Applications/jdk1.8.0_73/jre/lib/ext/nashorn.jar:/home/johnreed/Applications/jdk1.8.0_73/jre/lib/ext/sunec.jar:/home/johnreed/Applications/jdk1.8.0_73/jre/lib/ext/sunjce_provider.jar:/home/johnreed/Applications/jdk1.8.0_73/jre/lib/ext/sunpkcs11.jar:/home/johnreed/Applications/jdk1.8.0_73/jre/lib/ext/zipfs.jar:/home/johnreed/Applications/jdk1.8.0_73/jre/lib/javaws.jar:/home/johnreed/Applications/jdk1.8.0_73/jre/lib/jce.jar:/home/johnreed/Applications/jdk1.8.0_73/jre/lib/jfr.jar:/home/johnreed/Applications/jdk1.8.0_73/jre/lib/jfxswt.jar:/home/johnreed/Applications/jdk1.8.0_73/jre/lib/jsse.jar:/home/johnreed/Applications/jdk1.8.0_73/jre/lib/management-agent.jar:/home/johnreed/Applications/jdk1.8.0_73/jre/lib/plugin.jar:/home/johnreed/Applications/jdk1.8.0_73/jre/lib/resources.jar:/home/johnreed/Applications/jdk1.8.0_73/jre/lib/rt.jar:/home/johnreed/sbtProjects/UnderstandingScala/target/scala-2.11/classes:/home/johnreed/.ivy2/cache/com.chuusai/shapeless_2.11/bundles/shapeless_2.11-2.3.1.jar:/home/johnreed/.ivy2/cache/org.scala-lang/scala-library/jars/scala-library-2.11.8.jar:/home/johnreed/.ivy2/cache/com.google.code.findbugs/jsr305/jars/jsr305-2.0.1.jar:/home/johnreed/.ivy2/cache/com.google.guava/guava/bundles/guava-16.0.1.jar:/home/johnreed/.ivy2/cache/com.twitter/jsr166e/jars/jsr166e-1.0.0.jar:/home/johnreed/.ivy2/cache/com.twitter/util-collection_2.11/jars/util-collection_2.11-6.34.0.jar:/home/johnreed/.ivy2/cache/com.twitter/util-core_2.11/jars/util-core_2.11-6.34.0.jar:/home/johnreed/.ivy2/cache/com.twitter/util-function_2.11/jars/util-function_2.11-6.34.0.jar:/home/johnreed/.ivy2/cache/commons-collections/commons-collections/jars/commons-collections-3.2.2.jar:/home/johnreed/.ivy2/cache/javax.inject/javax.inject/jars/javax.inject-1.jar:/home/johnreed/.ivy2/cache/org.scala-lang.modules/scala-parser-combinators_2.11/bundles/scala-parser-combinators_2.11-1.0.4.jar:/home/johnreed/.ivy2/cache/org.typelevel/macro-compat_2.11/jars/macro-compat_2.11-1.1.1.jar:/home/johnreed/.ivy2/cache/scala.trace/scala-trace-debug_2.11/jars/scala-trace-debug_2.11-2.2.14.jar:/home/johnreed/Applications/idea-IC-145.258.11/lib/idea_rt.jar pkg.Main
Connected to the target VM, address: '127.0.0.1:34395', transport: 'socket'
Disconnected from the target VM, address: '127.0.0.1:34395', transport: 'socket'
Exception in thread "main" java.lang.NoClassDefFoundError: scala/reflect/api/TypeCreator
    at pkg.Main.main(Main.scala)
Caused by: java.lang.ClassNotFoundException: scala.reflect.api.TypeCreator
    at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
    ... 1 more

Process finished with exit code 1

I only get this error when I run from IntelliJ. When I run it from SBT with sbt run, it works fine. sbt compile works file too. How do I fix this so my project runs as an Application?

* Solution *

Manually add scala-reflect-2.11.8.jar

Answer 1

For me the following worked (without including scala-reflect to classpath):

• Go to run configurations
• Check the box Include dependencies with "Provided" scope

Answer 2

Please try running

sbt package

from the command line first. Then let us know if that fixes the issue.

Update Looked more closely. This is due to scala-reflect.jar not being picked up within intellij. You do have it the build.sbt:

"org.scala-lang" % "scala-reflect" % version % "provided",

Please add that dependency manually to the intellij project. Why IJ did not pick it up is uncertain so this is basically a hack. But with intellij fixes like this are unfortunately sometimes required.