ClassNot found exception in helloworld program in scala - scala

I am new to IntelliJ and scala and I am writing a helloworld program in sbt. But I am getting below error message :
(https://i.stack.imgur.com/SwL9Y.png)

Check if you have defined a JDK and Scala SDK in your Module Settings (F4)
enter image description here
Can you tell me what I am missing here

Related

Compilation error in the Scala/Play example application for Heroku using Intellij

I am trying to compile the scala/Play framework example application on my local machine, but I am getting compilation errors when trying to compile using the SBT console in IntelliJ:
error: scala.reflect.internal.MissingRequirementError: object java.lang.Object in compiler mirror not found.
I also got this message in the event log related to different SBT versions:
14:48 Started sbt shell with sbt version 0.13.18 instead of 0.13.11 configured by project.
Update sbt version
Disable version override
Any suggestions on how to fix this?
For the first error
error: scala.reflect.internal.MissingRequirementError: object java.lang.Object in compiler mirror not found.
You might want to try and ensure that you are using a compatible java version. Like #cbley suggested, try making you are using version 8 of the JDK.
For the second error
14:48 Started sbt shell with sbt version 0.13.18 instead of 0.13.11 configured by project.
Update sbt version
Disable version override
Its just suggesting you update the version of sbt (which is most likely declared in your build.properties file in a folder called project. You can just search for it by double tapping shift in IntelliJ. But you are safe to ignore it if you cloned some example repository as well.
check

Cannot sync scala project in IntelliJ IDEA Community 2019.2.4

Scala newbie here: I am attempting to get started with Scala using Windows 10 (Pro 10.0.18362 Build 18362) Hyper-v Quick Create of Ubuntu (18.04.3 LTS). I installed the JRE and JDK (11.0.4). I installed IntelliJ IDEA 2019.2.4. I added the Plugin for Scala (plugin 2019.2.37). I have left the SBT Executor 1.2.1 disabled for now: it was enabled earlier but it does not seem to affect the results. I tried to create the HelloWorld application (see below). I added the Scala Framework to the Project and, after encountering the error below, the Mavin framework (adding Mavin did not help.) After correcting the error in bulid.sbt it looks like this:
import com.sun.tools.javac.resources.version
name := "HelloWorld"
version := "0.1"
scalaVersion := "2.13.1"
I create a Scala worksheet by right-click on scala folder and selecting Scala Worksheet:
object Hello extends App {
println("Hello, World!")
}
I get a pop-up saying Maven project needs to be imported. This succeeds quickly. I get a second one saying sbt project needs to be imported. This fails:
sbt.librarymanagement.ResolveException: Error downloading org.scala-sbt:zinc-compile-core_2.12:1.3.1
and this error accompanies it:
not found: https://repo.scala-sbt.org/scalasbt/sbt-plugin-releases/org.scala-sbt/util-position_2.12/1.3.2/ivys/ivy.xml
The first ResolveException appears to be about a part of Mavin, but that should be present. This error message is followed by many other "not found" errors, but I assume they all stem from the above errors or are related. I cannot seem to find a solution: most of the information and examples on IntelliJ IDEA Scala on the web are several years (editions) out of date.
It appears Maven apps are to be deployed to Apache Spark. Not my intention, but in the Mavin panel I can successfully clean, validate and compile.
When I Run the Hello.sc app, I get this:
/snap/intellij-idea-community/185/jbr/bin/java -javaagent:/snap/intellij-idea-community/185/lib/idea_rt.jar=37033:/snap/intellij-idea-community/185/bin -Dfile.encoding=UTF-8 -classpath /home/perfwise/ideaProjects/HelloWorld/target/classes:/home/perfwise/.ivy2/cache/org.scala-lang/scala-library/jars/scala-library-2.13.1.jar:/home/perfwise/.ivy2/cache/org.scala-lang/scala-reflect/jars/scala-reflect-2.13.1.jar:/home/perfwise/.ivy2/cache/org.scala-lang/scala-library/srcs/scala-library-2.13.1-sources.jar:/home/perfwise/.ivy2/cache/org.scala-lang/scala-reflect/srcs/scala-reflect-2.13.1-sources.jar Hello
Error: Could not find or load main class Hello
Caused by: java.lang.ClassNotFoundException: Hello
Process finished with exit code 1
I would have expected this to work. Any pointers will be much appreciated.

Running Scala under Eclipse

I'm very new to Scala and I tried to run Scala project under Eclipse. I used sbt to create one, then ran sbteclipse to prepare it for Eclipse and imported it successfully. However when I try to run it I get
Error: Unable to initialize main class Main
Caused by: java.lang.NoClassDefFoundError: scala/Function0
error. Scala, sbt and Java are installed, because when I try to run the same project via console, using sbt, it works. What am I missing?
Thanks for any help!
It looks like the classpath of your Eclipse project is incomplete: it's missing the Scala library. Can you double check in Project Settings that the scala library is present?
If all you want to do is try a simple program, an simpler solution is to create a New Scala Project using the Eclipse wizard.

intellij scala plugin won't compile after package rename

I'm using intellij 14.0.2 build#ic-139.659 and scala plugin 1.2.1
Im working on a basic project for a while and everything went well until i rename a package name.
Since then im getting this error and i cant compile and run the program
Error:(10, 8) not found: object Repo
import Repo._
^
When i'm generating the same code to eclipse it compile and run well.
Is that a bug or i`m doing something wrong ?
thanks,
miki

Bad class file error when using Scala 2.8.x (2.8.0 and 2.8.1) in Javafx 1.x (1.2 and 1.3.1)

When trying to import scala.Option in a javafx script, I get the following javafxc error:
cannot access scala.Option.$anonfun$orNull$1
bad class file: scala/Option$$anonfun$orNull$1.class(scala:Option$$anonfun$orNull$1.class)
undeclared type variable: A1
Please remove or make sure it appears in the correct subdirectory of the classpath.
import scala.Option;
I am using Scala 2.8.1, Javafxc 1.3.1_b101, JVM 1.6.0_21-b06, OS Ubuntu 10.10. The same code was working in Scala 2.7.7 .
Later edit:
The same error is reported in case I import scala.immutable.Seq/List/Traversable/Iterable . I have tried the imports in a default Netbeans 6.9.1 JavaFX project which has in the classpath only scala-library.jar.
It reminded me first of #4067, but this one looks quite different.
I would suggest that you try to reproduce the error with 2.8.1 or 2.9 trunk, maybe it is fixed?