scala,jar,build,sbt , Cannot run jar file created from scala file


Cannot run jar file created from scala file

Question:

Tag: scala,jar,build,sbt

This the code that I have written in scala.

object Main extends App {
    println("Hello World from Scala!")
}

This is my build.sbt.

name := "hello-world"
version := "1.0"
scalaVersion := "2.11.5"
mainClass := Some("Main")

This is the command that I have run to create the jar file.

sbt package

Problem : A jar file named hello-world_2.11-1.0.jar has been created at target/scala-2.11. But I cannot run the file. It is giving me an error saying NoClassDefFoundError.

Question : What am I doing wrong? I hope I have made my question clear. If there is some confusion then please ask. Thanks in advance.


Answer:

It also says what class is not found. Most likely you aren't including scala-library.jar. You can run scala target/scala-2.11/hello-world_2.11-1.0.jar if you have Scala 2.11 available from the command line or java -cp <path to scala-library.jar> -jar target/scala-2.11/hello-world_2.11-1.0.jar.


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