Scala InputStream for Memory Mapped File

MemoryMapInputStream.scala

// Just an example of some code I ended up not using, but which is kinda neat.

object Utils {

  def linesFromFile(file: File) = {
    io.Source.fromInputStream(getMemoryMappedFileInputStream(file)).getLines
  }

  def getMemoryMappedFileInputStream(file: File): InputStream = {
    val channel: FileChannel = new FileInputStream(file).getChannel()
    var buffer: ByteBuffer = channel.map(FileChannel.MapMode.READ_ONLY, 0, channel.size().toInt)
    getMemoryMappedInputStream(buffer)
  }

  private def getMemoryMappedInputStream(buffer: ByteBuffer) =
    new InputStream() {
      override def read(): Int =
        if (buffer.hasRemaining()) buffer.get else -1

      override def read(bytes: Array[Byte], off: Int, len: Int): Int = {
        if (buffer.hasRemaining()) {
          val length = scala.math.min(len, buffer.remaining())
          buffer.get(bytes, off, length)
          length
        } else {
          -1
        }
      }
    }
}