Android Multicast Client - written in Scala

AndroidMulticastActivity.scala

package org.test.android.multicast

import _root_.android.app.Activity
import _root_.android.os.Bundle
import _root_.android.widget.TextView
import _root_.android.app.Dialog
import _root_.android.util.Log
import _root_.android.net.wifi.WifiManager
import _root_.android.content.Context

class AndroidMulticastActivity extends Activity {

  import java.net.{DatagramPacket, InetAddress, MulticastSocket, SocketTimeoutException}
  import java.util.{Timer, TimerTask}
  import java.lang.StringBuilder

  class UdpClient(val address: String, val port: Int, val dataBuffer: StringBuilder) {
    private val socket = new MulticastSocket(port)
    private val group = InetAddress.getByName(address)
    socket.joinGroup(group)
    socket.setSoTimeout(250)
    dataBuffer.append(group.isMulticastAddress().toString)
    private val receiveTimer = new Timer("receiveTimer",true)
    private val receiverTask = new ReceiverTask
    receiveTimer.schedule(receiverTask, 2000)

    private class ReceiverTask extends TimerTask {
      private var finished = false
      override def run = {finished = true}
      def isFinished = finished
    }
    
    def execute: Unit = {
      val msg = "QUERY"
      val data = new DatagramPacket(msg.getBytes(), 0, msg.length(), group, port)
      socket.send(data)
      while(!receiverTask.isFinished){
        receive
      }
    }

    private def receive: Unit = {
      val buffer = Array.ofDim[Byte](1024)
      val receivedPacket = new DatagramPacket(buffer, buffer.length)
      try{
        socket.receive(receivedPacket)
        val message = new String(receivedPacket.getData)
        dataBuffer.append(message)
      }catch{
        case e:SocketTimeoutException => //
      }
    }

  }

  override def onCreate(savedInstanceState:Bundle):Unit = {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.main)
    val text = findViewById(R.id.content).asInstanceOf[TextView]
    val wifiManager = getSystemService(Context.WIFI_SERVICE).asInstanceOf[WifiManager]
    val multicastLock = wifiManager.createMulticastLock("myMulticastLock").asInstanceOf[wifiManager.MulticastLock]
    multicastLock.setReferenceCounted(true)
    multicastLock.acquire
    val dataBuffer = new StringBuilder
    new UdpClient("230.0.0.1",1234,dataBuffer).execute
    multicastLock.release
    text.setText(dataBuffer.toString)
  }
}