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scalagradleplayframeworklagom

Lagom with Gradle - java.lang.NoClassDefFoundError: scala/Function1$class

I am trying to run a Lagom service using Gradle - this might not seem to be a good idea, but I decided to give it a try for learning purposes.

You can browse the repository here: https://github.com/ashofthephoenix/lagom-gradle-helloworld

When I cd into hello-impl and execute gradle -t runPlayBinary in the console - the service works.

When I run the same command from the project level directory, it gives me this stack trace:

java.lang.NoClassDefFoundError: scala/Function1$class
    at play.docs.Memoise.<init>(DocumentationHandler.scala:118)
    at play.docs.DocumentationHandler.<init>(DocumentationHandler.scala:26)
    at play.docs.DocumentationHandler.<init>(DocumentationHandler.scala:22)
    at play.docs.BuildDocHandlerFactory.fromJar(BuildDocHandlerFactory.java:88)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.gradle.play.internal.run.DefaultVersionedPlayRunAdapter.getBuildDocHandler(DefaultVersionedPlayRunAdapter.java:140)
    at org.gradle.play.internal.run.PlayWorkerServer.startServer(PlayWorkerServer.java:91)
    at org.gradle.play.internal.run.PlayWorkerServer.start(PlayWorkerServer.java:76)
    at org.gradle.play.internal.run.PlayWorkerServer.execute(PlayWorkerServer.java:60)
    at org.gradle.play.internal.run.PlayWorkerServer.execute(PlayWorkerServer.java:36)
    at org.gradle.process.internal.worker.child.ActionExecutionWorker.execute(ActionExecutionWorker.java:83)
    at org.gradle.process.internal.worker.child.ActionExecutionWorker.execute(ActionExecutionWorker.java:35)
    at org.gradle.process.internal.worker.child.SystemApplicationClassLoaderWorker.call(SystemApplicationClassLoaderWorker.java:119)
    at org.gradle.process.internal.worker.child.SystemApplicationClassLoaderWorker.call(SystemApplicationClassLoaderWorker.java:64)
    at worker.org.gradle.process.internal.worker.GradleWorkerMain.run(GradleWorkerMain.java:62)
    at worker.org.gradle.process.internal.worker.GradleWorkerMain.main(GradleWorkerMain.java:67)
Caused by: java.lang.ClassNotFoundException: scala.Function1$class
    at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
    ... 19 more

Could somebody tell me what is the problem here?

Thank you.

Solution

  • Lagom provides sbt and Maven plugins to allow them to launch multiple services, inject configuration into each, and allow them to discover each other using a service locator.

    To do the same in Gradle would require writing a similar Gradle plugin. No such thing exists currently. Gradle's Play support has only been designed to work with traditional Play projects that contain a single application.

    There is an open feature request to add official Gradle support to Lagom (https://github.com/lagom/lagom/issues/146).