nuprocess.sc

import $ivy.`com.zaxxer:nuprocess:2.0.0`, com.zaxxer.nuprocess._

import scala.collection.JavaConverters._
import java.nio.ByteBuffer
import scala.concurrent.{Future, Promise}

class ProcessHandler extends NuAbstractProcessHandler {
   private var nuProcess: NuProcess = null

   override def onStart(nuProcess: NuProcess): Unit = {
      this.nuProcess = nuProcess
   }
   
   override def onStdout(buffer: ByteBuffer, closed: Boolean): Unit = {
      if (!closed) {
         val bytes = new Array[Byte](buffer.remaining())
         buffer.get(bytes);
         Console.println(new String(bytes));
         nuProcess.closeStdin(true);
      }
   }
}

val pb = new NuProcessBuilder(List("/bin/cat").asJava)
pb.setProcessListener(new ProcessHandler)
val process = pb.start()

process.writeStdin(ByteBuffer.wrap("Hello World!".getBytes("UTF-8")))
process.waitFor(0, java.util.concurrent.TimeUnit.SECONDS)