I am trying to run a play framework(2.1) application which is written in Scala but getting some error.
I need to use Play framework 2.1 only.
As per build.sbt file, I am using Scala 2.11.7.
sbt.version=0.13.8 is in project/build.properties.
I have installed Play 2.1.0 and changed my directory to application's root directory and then executed play command.
I got following error:
java.lang.NoClassDefFoundError: scala/StringContext
at sbt.CommandStrings$.<init>(CommandStrings.scala:83)
at sbt.CommandStrings$.<clinit>(CommandStrings.scala)
at sbt.BuiltinCommands$.defaults(Main.scala:202)
at sbt.xMain.run(Main.scala:29)
at xsbt.boot.Launch$.run(Launch.scala:55)
at xsbt.boot.Launch$$anonfun$explicit$1.apply(Launch.scala:45)
at xsbt.boot.Launch$.launch(Launch.scala:69)
at xsbt.boot.Launch$.apply(Launch.scala:16)
at xsbt.boot.Boot$.runImpl(Boot.scala:31)
at xsbt.boot.Boot$.main(Boot.scala:20)
at xsbt.boot.Boot.main(Boot.scala)
Caused by: java.lang.ClassNotFoundException: scala.StringContext
at java.net.URLClassLoader$1.run(URLClassLoader.java:366)
at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
at java.lang.ClassLoader.loadClass(ClassLoader.java:425)
at java.lang.ClassLoader.loadClass(ClassLoader.java:358)
... 11 more
Error during sbt exeenter code herecution: java.lang.NoClassDefFoundError: scala/StringContext
Can someone please tell me what's wrong here?
I am completely new to scala and I just need to run this app at earliest.
I am using 64-bit Cent OS 7(in case someone wants to know about OS).
The easiest way to fix that is to use an older version of SBT. Play 2.1.5 uses 0.12.2 by default, so you can change the file project/build.properties inside your project and use that version:
sbt.version=0.12.2
You can later try newer versions of SBT if you need.
sbt.version=0.12.2 wont work with JDK8 so you might need to downgrade Java.
I used this sbt version and got the following error
eror: error while loading CharSequence, class file '/usr/lib/jvm/java-8-openjdk-amd64/jre/lib/rt.jar(java/lang/CharSequence.class)' is broken for sbt 0.12.2
Related
When right-click running a test class, Eclipse failed with
Caused by: java.lang.NoClassDefFoundError: scala/Product$class
at org.scalatest.time.Days$.<init>(Units.scala:291)
at org.scalatest.time.Days$.<clinit>(Units.scala)
at org.scalatest.time.Span$.<init>(Span.scala:585)
at org.scalatest.time.Span$.<clinit>(Span.scala)
at org.scalatest.tools.Runner$.<init>(Runner.scala:779)
at org.scalatest.tools.Runner$.<clinit>(Runner.scala)
at org.scalatest.tools.Runner.main(Runner.scala)
... 6 more
Caused by: java.lang.ClassNotFoundException: scala.Product$class
at java.net.URLClassLoader.findClass(URLClassLoader.java:382)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
... 13 more
Yet it ran in the command line with sbt test. The libraries have been updated as described in java.lang.NoClassDefFoundError: scala/Product$class.
This happened with the latest Scala IDE (4.7.0-vfinal-2017-09-29T14:34:02Z-Typesafe) with the patmat project from Coursera's scala course.
What is the cause and how can it be fixed?
Requested info
The Java Build Path is
You have a combination of _2.11 libraries and 2.12.3 Scala library, this won't work. It looks like the _2.11 dependendencies come from SBT (judging from the paths).
You need to either change Scala IDE's Scala version (setting correct scala version on scala ide explains how) or set scalaVersion := "2.12.3" in the SBT project and rerun sbt eclipse.
Please use the Scala library version 2.11 as the other Scala based dependencies like scala-xml and scalatest are based on Scala library version 2.11
I have a Gradle project in IntelliJ IDEA 2016.2. Everytime I run the Scala tests in the project, I get the following exception:
Exception in thread "main" java.lang.reflect.InvocationTargetException
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 com.intellij.rt.execution.CommandLineWrapper.main(CommandLineWrapper.java:48)
Caused by: java.lang.ClassNotFoundException: org.jetbrains.plugins.scala.testingSupport.scalaTest.ScalaTestRunner
at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:264)
at com.intellij.rt.execution.application.AppMain.main(AppMain.java:123)
... 5 more
I checked the versions of the dependencies and I have added the Scala SDK to the project module as well. I also added the Scala plugin to the Gradle file and installed the Scala plugin in IntelliJ IDEA. Also, the tests run without an error on my colleague's computer so we have no idea what the error could be.
Found the cause: I have an accentuated letter in my user directory's name and IDEA is always trying to use some file from AppData under that directory. I have already changed the idea.properties file, but it has no effect regarding that file.
A possible workaround is using gradle (or maven/sbt/etc.). In my case, I use gradle, I just add #RunWith(classOf[JUnitRunner]) to the scala class I want to test, then execute gradle's test task.
For me the solution of command line length limitation was crucial. Idea offers about 3 ways of how to overcome too long command. Choose another and check.
It's in run configurations.
Running Specs2 in IntelliJ fails. Running the same tests manually via an SBT task works just fine without any problems.
Message: "Test framework quit unexpectedly"
IntelliJ: v.15.0.5 or 2016.2 EAP (build #IC-162.426.1)
Platform: Scala 2.11.7, SBT 0.13.8, Specs2 2.4.17, Play! 2.3.10
This is a common error response, but it looks like the root cause is different for a lot of other people. I have troubleshoot this issue before and corrected it by adding the following to build.sbt:
fork in Test := false
parallelExecution in Test := false
Now the tests are failing again. I have looked through the revision history of our build.sbt file but I do not notice anything significant that would instigate such a regression and I have no clues.
Upon step-debugging the crash I have found the following root cause:
java.lang.reflect.InvocationTargetException
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:526)
at org.specs2.reflect.Classes$class.createInstanceFor(Classes.scala:154)
at org.specs2.reflect.Classes$.createInstanceFor(Classes.scala:207)
at org.specs2.reflect.Classes$$anonfun$createInstanceOfEither$1.apply(Classes.scala:145)
at org.specs2.reflect.Classes$$anonfun$createInstanceOfEither$1.apply(Classes.scala:145)
at scala.Option.map(Option.scala:146)
at org.specs2.reflect.Classes$class.createInstanceOfEither(Classes.scala:145)
at org.specs2.reflect.Classes$.createInstanceOfEither(Classes.scala:207)
at org.specs2.reflect.Classes$class.org$specs2$reflect$Classes$$createInstanceForConstructor(Classes.scala:118)
at org.specs2.reflect.Classes$$anonfun$4.apply(Classes.scala:98)
at org.specs2.reflect.Classes$$anonfun$4.apply(Classes.scala:98)
at scala.collection.immutable.List.map(List.scala:273)
at org.specs2.reflect.Classes$class.tryToCreateObjectEither(Classes.scala:98)
at org.specs2.reflect.Classes$.tryToCreateObjectEither(Classes.scala:207)
at org.specs2.reflect.Classes$class.tryToCreateObject(Classes.scala:70)
at org.specs2.reflect.Classes$.tryToCreateObject(Classes.scala:207)
at org.specs2.specification.SpecificationStructure$.createSpecificationFromClassOrObject(BaseSpecification.scala:126)
at org.specs2.specification.SpecificationStructure$.createSpecificationOption(BaseSpecification.scala:107)
at org.specs2.specification.SpecificationStructure$.createSpecification(BaseSpecification.scala:95)
at org.specs2.runner.ClassRunner.createSpecification(ClassRunner.scala:60)
at org.specs2.runner.ClassRunner.start(ClassRunner.scala:31)
at org.specs2.runner.NotifierRunner.start(NotifierRunner.scala:25)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.jetbrains.plugins.scala.testingSupport.specs2.JavaSpecs2Runner.runSpecs2_old(JavaSpecs2Runner.java:133)
at org.jetbrains.plugins.scala.testingSupport.specs2.JavaSpecs2Runner.runSingleTest(JavaSpecs2Runner.java:204)
at org.jetbrains.plugins.scala.testingSupport.specs2.JavaSpecs2Runner.main(JavaSpecs2Runner.java:85)
Caused by: java.lang.IncompatibleClassChangeError: Found class scalaz.Tree, but interface was expected
at org.specs2.mutable.SideEffectingCreationPaths$class.$init$(FragmentsBuilder.scala:245)
at org.specs2.mutable.Specification.<init>(Specification.scala:12)
at controllers.VerificationApiSpec.<init>(VerificationApiSpec.scala:26)
... 32 more
scalaz.Tree is a transitive dependency of many other dependencies in my project that request versions including 7.1.1, 7.1.2, 7.1.3, 7.0.6 of scalaz. It's interesting to note that in 7.0.x scalaz.Tree is a trait (interface in Java vernacular) but an abstract class in 7.1.x, so this may constitute the root cause.
Is it possible to resolve this issue given the transitive dependency conflicts with scalaz 7.1.x and 7.0.x which are evidentially incompatible?
Specs2 2.4.17 uses Scalaz 7.1.0. Some other dependency in your build is probably dragging a Scalaz 7.2.x dependency. I suggest that you update your specs2 version to 3.8.4 which will bring a more recent version of Scalaz in scope.
Problem:
IntelliJ is not letting me import a play framework project. It just displays errors when I try to open project using SBT.
Its really simple what I want to do, but I haven't used any of these tools and I'm a bit lost at how to fix this.
I just want to create a Play framework project, and edit it in IntelliJ as shown on multiple tutorials on youtube.
Below I have provided some info about how I have tried to make it work to "help you help me".
I really hope there is some easy solution that I fail to see!
Background info:
I have downloaded and installed IntelliJ 14.1.5 Community Edition and the latest avtivator from Play Framework - Activator 1.3.6 and Play 2.4.3
Note: I also downloaded the latest java jdk, 1.8.0_65 and added both java and activator to path - I'm using Windows 8. I have also downloaded the latest plugin of Scala inside IntelliJ
Then I opened cmd and typed "activator ui" and opened browser at localhost:8888 as instructed in tutorials. I managed to create a "play-java-intro" project. So far, so good.
After this I have tried a few different approaches.
NOTE: I have clicked "Invalidate cache / restart" each time I try something new
First try
I tried to Open project after I had created the project through activator. I selected root directory of the project and selected SDK jdk 1.7 (have tried with 1.8 aswell).
I got the error
Error while importing SBT project: ... at
sbt.MainLoop$$anonfun$runWithNewLog$1.apply(MainLoop.scala:70) at sbt.MainLoop$$anonfun$runWithNewLog$1.apply(MainLoop.scala:65) at sbt.Using.apply(Using.scala:24) at sbt.MainLoop$.runWithNewLog(MainLoop.scala:65) at sbt.MainLoop$.runAndClearLast(MainLoop.scala:48) at sbt.MainLoop$.runLoggedLoop(MainLoop.scala:32) at sbt.MainLoop$.runLogged(MainLoop.scala:24) at sbt.StandardMain$.runManaged(Main.scala:53) at sbt.xMain.run(Main.scala:28) at xsbt.boot.Launch$$anonfun$run$1.apply(Launch.scala:109) at xsbt.boot.Launch$.withContextLoader(Launch.scala:129) at xsbt.boot.Launch$.run(Launch.scala:109) at xsbt.boot.Launch$$anonfun$apply$1.apply(Launch.scala:36) at xsbt.boot.Launch$.launch(Launch.scala:117) at xsbt.boot.Launch$.apply(Launch.scala:19) at xsbt.boot.Boot$.runImpl(Boot.scala:44) at xsbt.boot.Boot$.main(Boot.scala:20) at xsbt.boot.Boot.main(Boot.scala) [error] java.lang.UnsupportedClassVersionError: com/typesafe/config/ConfigException : Unsupported major.minor version 52.0 [error] Use 'last' for the full log.
Inside the log file:
[info] Loading project definition from C:\play-java-intro\project
[info] Set current project to play-java-intro (in build file:/C:/play-java-intro/)
java.lang.UnsupportedClassVersionError: com/typesafe/config/ConfigException : Unsupported major.minor version 52.0
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:800)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:449)
at java.net.URLClassLoader.access$100(URLClassLoader.java:71)
at java.net.URLClassLoader$1.run(URLClassLoader.java:361)
at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
at java.lang.ClassLoader.loadClass(ClassLoader.java:425)
at java.lang.ClassLoader.loadClass(ClassLoader.java:358)
at com.typesafe.sbt.web.SbtWeb$$anonfun$com$typesafe$sbt$web$SbtWeb$$load$1.apply(SbtWeb.scala:535)
at com.typesafe.sbt.web.SbtWeb$$anonfun$com$typesafe$sbt$web$SbtWeb$$load$1.apply(SbtWeb.scala:535)
at scala.Option.fold(Option.scala:157)
at com.typesafe.sbt.web.SbtWeb$.com$typesafe$sbt$web$SbtWeb$$load(SbtWeb.scala:549)
at com.typesafe.sbt.web.SbtWeb$$anonfun$globalSettings$1$$anonfun$apply$1.apply(SbtWeb.scala:143)
at com.typesafe.sbt.web.SbtWeb$$anonfun$globalSettings$1$$anonfun$apply$1.apply(SbtWeb.scala:143)
at scala.Function1$$anonfun$andThen$1.apply(Function1.scala:55)
at sbt.Project$.setProject(Project.scala:319)
at sbt.BuiltinCommands$.doLoadProject(Main.scala:484)
at sbt.BuiltinCommands$$anonfun$loadProjectImpl$2.apply(Main.scala:475)
at sbt.BuiltinCommands$$anonfun$loadProjectImpl$2.apply(Main.scala:475)
at sbt.Command$$anonfun$applyEffect$1$$anonfun$apply$2.apply(Command.scala:58)
at sbt.Command$$anonfun$applyEffect$1$$anonfun$apply$2.apply(Command.scala:58)
at sbt.Command$$anonfun$applyEffect$2$$anonfun$apply$3.apply(Command.scala:60)
at sbt.Command$$anonfun$applyEffect$2$$anonfun$apply$3.apply(Command.scala:60)
at sbt.Command$.process(Command.scala:92)
at sbt.MainLoop$$anonfun$1$$anonfun$apply$1.apply(MainLoop.scala:98)
at sbt.MainLoop$$anonfun$1$$anonfun$apply$1.apply(MainLoop.scala:98)
at sbt.State$$anon$1.process(State.scala:184)
at sbt.MainLoop$$anonfun$1.apply(MainLoop.scala:98)
at sbt.MainLoop$$anonfun$1.apply(MainLoop.scala:98)
at sbt.ErrorHandling$.wideConvert(ErrorHandling.scala:17)
at sbt.MainLoop$.next(MainLoop.scala:98)
at sbt.MainLoop$.run(MainLoop.scala:91)
at sbt.MainLoop$$anonfun$runWithNewLog$1.apply(MainLoop.scala:70)
at sbt.MainLoop$$anonfun$runWithNewLog$1.apply(MainLoop.scala:65)
at sbt.Using.apply(Using.scala:24)
at sbt.MainLoop$.runWithNewLog(MainLoop.scala:65)
at sbt.MainLoop$.runAndClearLast(MainLoop.scala:48)
at sbt.MainLoop$.runLoggedLoop(MainLoop.scala:32)
at sbt.MainLoop$.runLogged(MainLoop.scala:24)
at sbt.StandardMain$.runManaged(Main.scala:53)
at sbt.xMain.run(Main.scala:28)
at xsbt.boot.Launch$$anonfun$run$1.apply(Launch.scala:109)
at xsbt.boot.Launch$.withContextLoader(Launch.scala:129)
at xsbt.boot.Launch$.run(Launch.scala:109)
at xsbt.boot.Launch$$anonfun$apply$1.apply(Launch.scala:36)
at xsbt.boot.Launch$.launch(Launch.scala:117)
at xsbt.boot.Launch$.apply(Launch.scala:19)
at xsbt.boot.Boot$.runImpl(Boot.scala:44)
at xsbt.boot.Boot$.main(Boot.scala:20)
at xsbt.boot.Boot.main(Boot.scala)
[error] java.lang.UnsupportedClassVersionError: com/typesafe/config/ConfigException : Unsupported major.minor version 52.0
[error] Use 'last' for the full log.
I have tried to search what this means, but the answers I find on google wont apply to my problem.
I have tried to select and deselect all of the options within SBT - Use auto-import, Download sources and docs etc.. But still the same error message.
Second try
Similar to first try, but I clicked "Create IntelliJ project" inside activator at localhost:8888 and then tried to import the project the same method as First try.
Third try
Open project and select the root directory, and I managed to import the project somewhat, but its moved project files to "project backup" and I got lots of warnings saying its based on a outdated version. Didn't quite understand this.
Fourth try
Create project from existing sources after creating the project at activator, and I got the project imported without warnings.
But when I open Application.java (or any other file for that matter), everything inside that file gets red underlined with a error saying similar to "Cannot resolve symbol 'Result'" and I cant compile anything.
I have tried to open modules and click + and add Scala as a module, but it doesn't seem to make any difference.
I really hope there is someone out there that can help me as this should be a fairly easy thing to install IntelliJ + Play framework.
The issue is that even if IntelliJ is set to use JDK8, the SBT process is using JDK7 (you can confirm that looking at it with a tool like JVisualVM). Not sure what their logic is to pick up SBT's JVM, but you can force it when you import the projet:
This solved it for me with this version of Idea:
From the documentation: https://www.playframework.com/documentation/2.4.x/Highlights24
Play 2.4 now requires JDK 8
So you definitely must use only JDK 8.
Unsupported major.minor version 52.0
Means that you try to open project that was compiled with JDK 8 but your settings in IDE is JDK 7 (or less)
My proposition - check twice if you really use JDK8 in the intelliJ
I'm unable to figure out what is wrong with this program? I'm using an older verison of scala (2.7) because its compatible with certain libraries i'm using
Here is a simple program i'm attempting to run.
The program runs fine using scalac and scala commands.
However on IntelliJ 14+ -> when i create a new project -> select the compiler (scala 2.7) and try to run the above program i get this error below
object SimpleClass {
def main(args: Array[String]) {
println("This is a simple Class")
}
}
Error output.
Why does intelliJ throw the ClassNotFoundException? I've saved the program as SimpleClass.scala
/usr/lib/jvm/java-7-openjdk-i386/bin/java -Didea.launcher.port=7532 -Didea.launcher.bin.path=/home/tejesh/Downloads/idea-IC-141.1532.4/bin -Dfile.encoding=UTF-8 -classpath /usr/lib/jvm/java-7-openjdk-i386/jre/lib/javazic.jar:/usr/lib/jvm/java-7-openjdk-i386/jre/lib/management-agent.jar:/usr/lib/jvm/java-7-openjdk-i386/jre/lib/resources.jar:/usr/lib/jvm/java-7-openjdk-i386/jre/lib/rhino.jar:/usr/lib/jvm/java-7-openjdk-i386/jre/lib/charsets.jar:/usr/lib/jvm/java-7-openjdk-i386/jre/lib/jce.jar:/usr/lib/jvm/java-7-openjdk-i386/jre/lib/jsse.jar:/usr/lib/jvm/java-7-openjdk-i386/jre/lib/rt.jar:/usr/lib/jvm/java-7-openjdk-i386/jre/lib/compilefontconfig.jar:/usr/lib/jvm/java-7-openjdk-i386/jre/lib/ext/localedata.jar:/usr/lib/jvm/java-7-openjdk-i386/jre/lib/ext/zipfs.jar:/usr/lib/jvm/java-7-openjdk-i386/jre/lib/ext/sunpkcs11.jar:/usr/lib/jvm/java-7-openjdk-i386/jre/lib/ext/dnsns.jar:/usr/lib/jvm/java-7-openjdk-i386/jre/lib/ext/java-atk-wrapper.jar:/usr/lib/jvm/java-7-openjdk-i386/jre/lib/ext/sunjce_provider.jar:/usr/lib/jvm/java-7-openjdk-i386/jre/lib/ext/icedtea-sound.jar:/usr/local/share/scala-2.7.3/lib/scala-swing.jar:/usr/local/share/scala-2.7.3/lib/scala-library.jar:/home/tejesh/Downloads/idea-IC-141.1532.4/lib/idea_rt.jar com.intellij.rt.execution.application.AppMain SimpleClass
Exception in thread "main" java.lang.ClassNotFoundException: SimpleClass
at java.net.URLClassLoader$1.run(URLClassLoader.java:366)
at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
at java.lang.ClassLoader.loadClass(ClassLoader.java:425)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308)
at java.lang.ClassLoader.loadClass(ClassLoader.java:358)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:191)
at com.intellij.rt.execution.application.AppMain.main(AppMain.java:122)
I've added the folder containing the SimpleClass as under sources
This is the full program here
Recent Scala for IntelliJ IDEA is based on sbt. Apparently Scala 2.7.3 is not supported any longer in this configuration. If you set up a project, IntelliJ will offer you (when you select "Download" for the SDK) no version older than Scala 2.8.0. If you manually select 2.7.3, the following happens when you try to compile:
Error:scalac: Error: org.jetbrains.jps.incremental.scala.remote.ServerException
Error compiling sbt component 'compiler-interface-2.7.3.final-52.0'
at sbt.compiler.AnalyzingCompiler$$anonfun$compileSources$1$$anonfun$apply$2.apply(AnalyzingCompiler.scala:145)
at sbt.compiler.AnalyzingCompiler$$anonfun$compileSources$1$$anonfun$apply$2.apply(AnalyzingCompiler.scala:142)
at sbt.IO$.withTemporaryDirectory(IO.scala:285)
at sbt.compiler.AnalyzingCompiler$$anonfun$compileSources$1.apply(AnalyzingCompiler.scala:142)
at
...
The next step is Scala 2.8.2, for which you get:
Error:scalac: Parameter '-nobootcp' is not recognised by Scalac.
It seems the oldest Scala that works with the current IntelliJ is 2.9.0. (You have to use Java 7 and not Java 8 for this!)
The solution would be to downgrade IntelliJ IDEA to an old version that still supports Scala 2.7.3 (perhaps IDEA 11?), or to simply set up the project with Scala 2.9.3, but compile instead manually (or using sbt from the terminal) against 2.7.3.
If you have the source to the library that requires 2.7.3, perhaps the best option is to try to compile the library with contemporary versions of Scala (at least 2.9.0).