SaferExceptions3.scala

package progscala3.rounding.saferexceptions
import java.io.{IOException, File}
import scala.annotation.experimental
import language.experimental.saferExceptions

@experimental
object SaferExceptionsNested:
  def main(fileNames: Array[String]): Unit =
    fileNames.foreach { fileName =>
      try
        val file = wrapper(fileName)
        val path = file.getCanonicalPath()
        val size = file.length()
        println(s"file $fileName ($path) has $size bytes.")
      catch
        case ioe: IOException => println(s"file $fileName: IOException caught: ${ioe.getMessage}")
    }

  def wrapper(fileName: String): File throws IOException = openExistingFile(fileName)

  def openExistingFile(fileName: String): File throws IOException =
    val file = new File(fileName)
    if file.exists() == false then throw new IOException(s"$fileName doesn't exist!")
    file