I use Scala 2.10.0RC1 and sbt 0.12.1.
What causes and how can I fix this runtime error (runs fine on 2.9.2)?
The exact error message is:
java.lang.NoSuchMethodError: scala.Predef$ArrowAssoc$.extension$$minus$greater(Ljava/lang/Object;Ljava/lang/Object;)Lscala/Tuple2;
You're running the code with the wrong Scala version. This can have several causes:
misconfiguration of the project with sbt – search for 2.9.2 in config files
stale cache used by sbt – sbt reboot
something else?
If you meticulously check all your sbt configuration files for 2.9.2 and then wipe out all caches, things should run better. Dependencies usually have a version number in the name of the jar file, so running a find on your system will likely point you to the ones you missed.
Related
I am using intellij 14 with scala 2.11.6 installed using home brew and symlink using
ln -s /usr/local/Cellar/scala/2.11.6/libexec/src /usr/local/Cellar/scala/2.11.6/src
ln -s /usr/local/Cellar/scala/2.11.6/libexec/lib /usr/local/Cellar/scala/2.11.6/lib
mkdir -p /usr/local/Cellar/scala/2.11.6/doc/scala-devel-docs
ln -s /usr/local/Cellar/scala/2.11.6/share/doc/scala /usr/local/Cellar/scala/2.11.6/doc/scala-devel-docs/api
I tried running a simple hello world but run into the following issue.
Error:scalac: Multiple 'scala-library*.jar' files (scala-library.jar, scala-library.jar, scala-library.jar) in Scala compiler classpath in Scala SDK scala-sdk-2.11.6
Edit:
So I check the compiler class path on global libraries and apparently there are multiple scal-library.jar
file:///usr/local/Cellar/scala/2.11.6/idea/lib/scala-library.jar
file:///usr/local/Cellar/scala/2.11.6/lib/scala-library.jar
file:///usr/local/Cellar/scala/2.11.6/libexec/lib/scala-library.jar
Does anyone know why?
Maybe you have used
/usr/local/Cellar/scala/2.11.6/
as the path for Scala SDK?
When you install scala with homebrew that path will contain not only the scala libraries, but also a symlink with the relevant libraries for intellij. So if you use the top-level install directory intellij will find the libraries twice.
Instead you should use
/usr/local/Cellar/scala/2.11.6/idea/lib
I had the same issue than you experimented and the solution, actually very easy, was actually erasing the .idea folder from the project, the problem is that the configuration inside of this folder (containing the set ups for example for the test, VCS, the runs, etc) gets corrupted with double entries (probably cos you update your Scala version), once you do this and reopen the project in Intellij the IDEA will generate a fresh new configuration for you.
This worked for me.
I'm using Idea 2019.2.2 and Windows 10.
In the folder .idea/libraries/ I had two files: sbt__org_scala_lang_scala_library_2_13_0_jar.xml and sbt__org_scala_lang_scala_library_2_13_0_jar2.xml.
I deleted the second file.
Then I opend the first one and there were duplicate lines:
<root url="file://$USER_HOME$/AppData/Local/Coursier/cache/v1/https/repo1.maven.org/maven2/jline/jline/2.14.6/jline-2.14.6.jar" />
<root url="file://$USER_HOME$/AppData/Local/Coursier/cache/v1/https/repo1.maven.org/maven2/org/scala-lang/scala-compiler/2.13.0/scala-compiler-2.13.0.jar" />
<root url="file://$USER_HOME$/AppData/Local/Coursier/cache/v1/https/repo1.maven.org/maven2/org/scala-lang/scala-compiler/2.13.0/scala-compiler-2.13.0.jar" />
<root url="file://$USER_HOME$/AppData/Local/Coursier/cache/v1/https/repo1.maven.org/maven2/org/scala-lang/scala-library/2.13.0/scala-library-2.13.0.jar" />
<root url="file://$USER_HOME$/AppData/Local/Coursier/cache/v1/https/repo1.maven.org/maven2/org/scala-lang/scala-library/2.13.0/scala-library-2.13.0.jar" />
<root url="file://$USER_HOME$/AppData/Local/Coursier/cache/v1/https/repo1.maven.org/maven2/org/scala-lang/scala-reflect/2.13.0/scala-reflect-2.13.0.jar" />
So I deleted duplicates and errors disappeared.
Hope this will help someone else.
I also ran into that error. The fix I found was to remove the duplicate scala-library in the .iml file generated by intellij.
Basically I located the relevant .iml file by grepping the scala version, and found that two scala-library in that file. I removed the scala 2.11 version, and then it works.
Remove the following line in build.sbt:
...
scalaVersion := "2.13.0"
...
Try rebuilding and running it again
2019 update... I'm running Ubuntu Linux and IntelliJ community 2019.1 with sbt 2.13.1 and got the exact same error. I also found that if I built directly from sbt with "runMain package.MyClass" it worked, so I knew it must be an IntelliJ problem, not a "real" problem.
Anyway, I found the file .idea/libraries/sbt.. lots of crazy long name ... scala_library_2_13_1_jar.xml.
In it, there was an XML block , and in that block, two entries were duplicated:
I first noticed the scala-library one, and after deleting that, the error report came up about the scala-compiler duplicate too.
After deleting both duplicates, my build is now working.
To fix the problem go to project structure in intellij and go to global libraries
It should be like this
After that remove all the scala SDKs by hitting the - mark
Next, click the + and choose your Scala SDK version to add
After that please make sure to apply the changes and re-run the program
You have JAR files from multiple versions of scala-library.jar. In order to make the error go away you will have to delete the duplicates. To figure out which version you want to keep, you can view the manifest file inside each JAR:
META-INF/MANIFEST.MF
Inside the manifest file you should see something like this:
Manifest-Version: 1.0
Class-Path:
Implementation-Title: Scala-Library
Implementation-Version: 2.11.4
The error is happening because IntelliJ cannot figure out which version of a given Scala class to use.
Delete multiple versions of scala-library in sbt, leaving one.
Having similar symptoms, but on a Ubuntu machine, not using brew:
I am using /usr/share/sbt/bin/sbt-launch.jar as launcher. To fix the mentioned problem, I've had to purge the directories 1) project, 2) target and 3) .idea of the relevant Scala projects, doing sbt refresh in IntelliJ (View - Tool Windows -> sbt, hit the Reimport all sbt projects icon), and rebuild all modules afterwards.
As a last step, when the error occurs further, switch over to Ubuntu shell / terminal, and do a sbt clean compile in the problematic project folder. Fix the compile issues if some are occuring. If this does not help, change scalaVersion in build.sbt e.g. from 2.12.9 to 2.12.8 (the error occurs more often with 2.12.9), remove scalaOrganization definition (but keep organization). Repeat the sbt refresh of IntelliJ. OMG.
This worked for me:
In IDEA
Preferences -> Plugins -> Scala -> Update
Restart IDEA
I'm using Typesafe Activator 1.3.2 on Windows 8.
Whenever I try to start activator using activator command, I am getting the following error:
C:\path>activator
Getting Scala 2.11.5 (for activator-launcher)...
:: retrieving :: org.scala-sbt#boot-scala
confs: [default]
0 artifacts copied, 6 already retrieved (0kB/15ms)
Error: Could not retrieve Scala 2.11.5: missing scala.Option, scala.tools.nsc.Global
Can any one help me on this issue?
Deleting ~/.sbt/boot fixes this issue.
I'm pretty sure the following directories have been corrupted and should be removed in that order:
~/.ivy2
~/.sbt
You may also want to rename them first before deleting (in case deleting them does not help and could be restored easily rather than downloading the whole Internet again).
I'm not on Windows and can't tell you exactly what ~ is resolved to on Windows 8 - it's the home directory of the logged-in user, and unless I'm mistaken it was something like %userprofile%.
Uninstall and Install
1) Scala plugin in intelliJ
2) SBT plugin in intelliJ
Restart the intelliJ and run the apps agian.
The below solution has worked for me.
NOTE: Below answer is specific to IntelliJ. But trying the same approach in Eclipse or other IDEs will also work.
In most cases your project JDK is not compatible with Scala or sbt version, try to change the Scala Compile Server SDK.
Press Ctrl+Alt+S to open Settings/Preferences dialog.
From the options on the left, select Build, Execution, Deployment | Compiler | Scala | Scala Compiler Server.
In the JVM SDK field specify the appropriate SDK.
I recommend that you switch to Java 8 SDK since the Scala version 2.12, and sbt versions 1.10 and later are not compatible with older Java SDK versions.
Deleting below two folders fixed the intelliJ error for me
rm -rf ~/.ivy2
cd ~/.sbt
rm -rf boot
I'm currently reading the Play for Scala: Covers Play 2 book by Peter Hilton (publisher: Manning) , and trying to stick to the versions they've outlined in the book (Play version 2.1.1).
I downloaded the new IntelliJ IDEA 14 CE app and installed it. I'm currently importing the project, and it's failing because it wants a version of sbt that is 0.12.4 or greater.
This issue occurred in 13 the other day, but I haven't had time to resolve it, so please, no recommendations to go back to 13 :)
Here is the meat of the issue:
When I type sbt --version on the CLI, it prints sbt launcher version 0.13.6. I have a "greater" version, but it appears that IDEA doesn't recognize this.
In an effort to specify my own SBT launcher JAR, I pointed my custom launcher (in IDEAs global settings) to the one in /usr/local/Cellar/sbt/0.13.6/libexec/sbt-launch.jar, but the build also failed with the same error.
As you may have guessed at this point, I have used Homebrew to install and manage Scala and sbt. When I first started working with Scala back in February, I remember having to make a few small tweaks in my settings to get IDEA to find Scala, but my version of IDEA 14 is totally fresh -- I did not import any previous settings. I downloaded the Scala and sbt plugins and they appear to be properly configured after a cursory look and creation of a new test project.
Here is what I'm failing to understand:
First, and most obvious, why would an sbt version that meets the supposed requirement (0.12.4+) fail with version 0.13.*?
Second, is the bundled sbt with IDEA also greater than this version? Is there possibly an sbt flag somewhere in my system that's pointing it to an earlier version? A side note, I have a few versions of sbt in my "Cellar", but all are greater than 0.13.
Many thanks for your help!
I had a look at the code samples from Manning's website, and the project/build.properties files for each project specify sbt.version=0.12.2. My guess is that the Intellij Scala plugin only supports SBT 0.12.4, and cannot import you project which is configured to use an older version (hence why it recommends that you "update your project definition").
You should try using sbt.version=0.12.4 in the project/build.properties file.
Generally speaking, keep in mind that when an SBT version is specified in project/build.properties, the SBT launcher downloads the specified version and uses it to build the project. In your case, that means that the SBT 0.13.6 launcher will download SBT 0.12.2 and use that version to build the project.
I have SBT and Scala installed and things work well.
Now I have an IntellIJ IDEA project, which works otherwise OK except that dependencies which are downloaded into /Users/MyName/.ivy2/cache/ are not understood.
I tried setting the cache path as a source folder:
but still things don't work out:
As you can see, org.eclipse is in red color meaning it can't find it. It must be inside that .jar file I showed on the left.
I just want to update/download dependencies using SBT, and then get the compilation to work in IntelliJ IDEA with those dependencies.
Use the sbt-idea plugin for SBT. Then you can run "gen-idea" from the sbt command line and it will generate the metadata files used by IDEA. These files contain the locations of jars as SBT uses them so that IDEA will know where the dependencies are, just like SBT.
I successfully implemented and ran several Scala tutorials in Eclipse using the Scala plugin. Then suddenly I tried to compile and run an example, and this error came up:
Exception in thread "main" java.lang.NoClassDefFoundError: hello/HelloWorld
Caused by: java.lang.ClassNotFoundException: hello.HelloWorld
at java.net.URLClassLoader$1.run(URLClassLoader.java:200)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
at java.lang.ClassLoader.loadClass(ClassLoader.java:315)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:330)
at java.lang.ClassLoader.loadClass(ClassLoader.java:250)
at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:398)
After this point I could no longer run any Scala programs in Eclipse. I tried cleaning and rebuilding my project, closing and reopening my project, and closing and reopening Eclipse.
Eclipse version number 3.5.2 and Scala plugin 2.8.0
Here is the original code:
package hello
object HelloWorld {
def main(args: Array[String]){
println("hello world")
}
}
If you see this when you attempt to run as a Scala application then the most likely explanation is that your project didn't compile and no class files were generated. Please check whether or not that's the case: look in your project's output folder for hello/HelloWorld.class.
If your project didn't compile that could either be because there's an error which you've missed (and if this error isn't being reported in the Problems view that could be a bug, in which case please open a ticket on Trac) or because you've turned off automatic builds and not done a manual build of your project.
I had the same problem. Project doesn't compile but there are no errors highlighted and AFAIK the code is OK. It seems to be a problem with the Run Configurations.
Solution 1: Delete the existing Run Configuration for your object and create a new one
Solution 2: Create a new object and cut / paste all your code into that file
When running "clean" does not un-hose Eclipse, I next try saving my work, exiting Eclipse, and re-starting. That usually gets things going again, but not always. A few times I've had to update the Scala plugin with a more recent version (I'm using the latest nightly), to get things working again. I doubt that this worked because the new plugin happened to fix the bug, but rather expect that loading the new plugin gives the whole Eclipse-Scala
system a "total reset" that gets it unhosed.
I was getting this problem in a project that combined .java & .scala files.
The solution for me was:
Remove all .java files
Edit the scala code as needed so it compiles without them.
Add the .java files back in.
Edit the scala code back.
The other solutions given here didn't work for me. I tried: clean project, restarting Eclipse, closing-&-opening the project, creating a new .scala file. No joy.
I'm using Eclipse 3.7 (latest stable), Scala IDE 2.0.0 and Scala 2.9 on Ubuntu Linux 11.10.
The symptoms in my case were:
My project was working, but then it stopped compiling for no apparent reason. The IDE didn't show any compilation errors for .scala files, but there were no .class files in the output directory & I got a NoClassDefError if I tried to run anything.
If I created a deliberate error in a .scala file, that did get picked up as a compilation error.
The .java files were registering errors due to the missing scala classes.
I suppose there's probably a boot-strapping bug somewhere in the IDE plugin for .java/.scala mixes. I've done hybrid projects with this setup without problems, so it's only triggered in some situations. I don't know what the trigger is, but once triggered, there's no nice solution.
I had moved my one and only class/object/application to a package, but had not added the package declaration.
sbt compiled and ran fine; eclipse would not
Adding the package declaration at the top of the file fixed it.
Scala 2.8.3 plugin; no compile error
I encountered this error too but after doing the suggestions here (cleaning, deleting Run Configuration etc), I realized that I set the workspace wrongly that is why the class is not being found.
An indication that this is a problem is when the same error occurs when you try to compile a java project.
I encountered this error (compilation worked in sbt but failed in eclipse) when I created a new package object called "common". Deleting the package object in eclipse caused the compile error to go away. There was nothing in it.
I was using sbt-eclipse to build the eclipse project. I'm using scala eclipse 3.0.0-vfinal-20130326-1146-Typesafe.