Missing dependency ‘object scala.native in compiler mirror’

Question

I used scala-compiler.jar to compile an embedded Scala program This scala program imports a class written using jni

• The code is as follows

class test{
  def test(ctx: ContractContext): ActionResult = {
    val s = new DllTest
    s.loadLibrary()
    print(s.intMethod(5))
    null
  }
}

DllTest is a jni application

• The error is as follows

error: error while loading Object, Missing dependency 'object scala.native in compiler mirror', required by /modules/java.base/java/lang/Object.class

Failed to initialize compiler: object scala in compiler mirror not found.
** Note that as of 2.8 scala does not assume use of the java classpath.
** For the old behavior pass -usejavacp to scala, or if using a Settings
** object programmatically, settings.usejavacp.value = true.

Anyone knows the reason? And how to solve the problem? Thanks for shedding some lights on it

It works fine in the main function

  def main(args: Array[String]): Unit = {

    //Create system instance
    val s = new DllTest
    s.loadLibrary()
    print(s.intMethod(5))
......

Answer 1

According to

object scala in compiler mirror not found - running Scala compiler programmatically

"scala.runtime in compiler mirror not found" but working when started with -Xbootclasspath/p:scala-library.jar

Why am I getting "object scala.runtime in compiler mirror not found." with scala-maven-plugin when dependency is upgraded?

object scala in compiler mirror not found - running Scala compiler programatically [no sbt - no IDE]

most probably you should try to switch on settings.usejavacp.value = true as written in the error message. How to feed this setting to the compiler depends on how you run it.

See examples how to run the compiler programmatically in

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I'm afraid the code you provided is not self-contained, so can't be used for reproduction. If you still experience issues please prepare MCVE.

Answer 2

Thanks for the answer, I have set the appropriate options in my code

val classCache = mutable.Map[String, Class[_]]()
private val settings = new Settings()
  settings.deprecation.value = true // enable detailed deprecation warnings
  settings.unchecked.value = true // enable detailed unchecked warnings
  settings.outputDirs.setSingleOutput(target)
  settings.usejavacp.value = true
  settings.classpath.append(getSourcePath())

  private val global = new Global(settings)
  private lazy val run = new global.Run
  val classLoader = new AbstractFileClassLoader(target, this.getClass.getClassLoader)

My testing environment is a system that uploads scala code and compiles and runs scala code. So I can't provide mcve. I submitted some scala programs that worked fine without importing jni, but whenever I tried to include jni code in my scala code, I got an error saying that scala.native was not found Here is my program

class DllTest {

  @native def intMethod(n: Int): Int

  def loadLibrary(): Unit = {
    System.load("D:\\Idea\\scala_test\\libtest.dll")
  }
}

It is then imported into the embedded scala code

import rep.DllTest
  def test(ctx: ContractContext): ActionResult = {
    val s = new DllTest
    s.loadLibrary()
    print(s.intMethod(5))
    null
  }

Is scala-compiler.jar unable to compile native methods? Moreover, the imported code works fine in the main system function, but scala-compiler.jar throws an error

After debugging, the code that throws the exception looks like this enter image description here