RTP Manager can't support multicast

Question

I want to transmitt voice from one to many using multicast address. I put "230.0.0.1" with port 2222.
I worked with this code (I show just on createTransmitter and stopStreaming method).
private String createTransmitter() {
     InetAddress ipAddr;
     SendStream sendStream;
     SourceDescription srcDesList[];
     String ipAddr = "230.0.0.1";
     int portBase = 2222;
     try {
            rtpMgrs = RTPManager.newInstance();
            ipAddr = InetAddress.getByName(ipAddress);
               localAddr = new SessionAddress(InetAddress.getLocalHost(), portBase);
               destAddr = new SessionAddres(ipAddr, portBase);
            rtpMgrs.initialize(localAddr);
            rtpMgrs.addTarget(destAddr);
            System.err.println("Created RTP session: " + ipAddress + " " + portBase);
            sendStream = rtpMgrs.createSendStream(dataOutput, 0);
            sendStream.start();
        } catch (Exception  e) {
            e.printStackTrace();
            return e.getMessage();
     return null;
public void stopStreaming() {
     synchronized (this) {
         if (processor != null) {
                try {
                    processor.stop();
                    processor.close();
                    processor = null;
                    rtpMgrs.removeTarget(destAddr, "destination disconnect");
                    rtpMgrs.removeTarget(localAddr, "local disconnect");
                    rtpMgrs.removeTargets("disconnect all");
                    rtpMgrs.dispose();
                } catch (InvalidSessionAddressException ex) {
                    Logger.getLogger(AudioTransmitter.class.getName()).log(Level.SEVERE, null, ex);
}I can using this, just once (start and stop then). When I'm going in second, I've got the error message that say
"javax.media.rtp.InvalidSessionAddressException: Can't open local data port: 22224"
I debug this, and found that the problem when I initialize RTP Manager. I have noticed that initialized() method just call once. But, I have stopped the stream, and make RTPManager removeTargets and dispose. Show where is the problem?
Edited by: 831279 on Apr 12, 2011 6:21 PM

Answer 1

Update :
I've tried work with AVTransmit2.java. It has same problem. Cannot open local port when meet second chance.
        String deviceName = "javasound://0";
        String ipDest = "224.112.112.112";
        String port = "22222";
     AVTransmit2 at = new AVTransmit2(new MediaLocator(deviceName),
                              ipDest, port, null);
     // Start the transmission
     String result = at.start();
     if (result != null) {
         System.err.println("Error : " + result);
         System.exit(0);
     System.err.println("Start transmission for 60 seconds...");
     try {
         Thread.currentThread().sleep(10000);
     } catch (InterruptedException ie) {
     // Stop the transmission
     at.stop();
        at = new AVTransmit2(new MediaLocator(deviceName), ipDest, port, null);
     result = at.start();
     if (result != null) {
         System.err.println("Error : " + result);
         System.exit(0);
     System.err.println("Start transmission for 60 seconds...");
     try {
         Thread.currentThread().sleep(60000);
     } catch (InterruptedException ie) {
     at.stop();
     System.err.println("...transmission ended.");
     System.exit(0);
result :
Track 0 is set to transmit as:
dvi/rtp, 8000.0 Hz, 4-bit, Mono
Created RTP session: 224.112.112.112 22222
Start transmission for 60 seconds...
Track 0 is set to transmit as:
dvi/rtp, 8000.0 Hz, 4-bit, Mono
Error : Can't open local data port: 22222
So, how to fix this? Thx for advance..