FileIO.scala

import java.nio.file._
import java.nio.file.attribute._

object FileIO {
  def deleteDirectories(dir: Path): Unit = {
    Files.walkFileTree(dir, new SimpleFileVisitor[Path] {
      override def visitFile(file: Path, attrs: BasicFileAttributes): FileVisitResult = {
        Files.delete(file)
        FileVisitResult.CONTINUE
      }

      override def postVisitDirectory(dir: Path, exc: IOException): FileVisitResult = {
        Files.delete(dir)
        FileVisitResult.CONTINUE
      }
    })
    Files.deleteIfExists(dir)
  }
}