Bluetooth

Programação Java
#1

estou com um problema, estou tentando chama o metodo sendMessagem, já com um valor certo e esta tanto erro.

public class conexao implements CommunicationListener, ConnectionListener {

    private MenuPrinc menuPrinc;
    private CommunicationFactory communicationFactory;
    public Device device;

    conexao(MenuPrinc menuPrinc) {
        this.menuPrinc = menuPrinc;
    }

    public conexao(CommunicationFactory communicationFactory) {
        this.communicationFactory = communicationFactory;
    }

    public void startServer() {
        ServerConfiguration config = new ServerConfiguration(this);
        config.setMaxNumberOfConnections(5);
        communicationFactory.waitClients(config, this);
    }

    public void errorOnConnection(IOException e) {
        System.err.println(e.getMessage());
    }

    public void connectionEstablished(ServerDevice device, RemoteDevice remote) {
        System.out.println(remote.getBluetoothAddress());
        this.device = device;
        device.startListening();
        device.setEnableBroadcast(true);
    }

    public void receiveMessage(byte[] receivedString) {
        String s = new String(receivedString);
        System.out.println("Recebido:"+s);
        this.device.send(("echo: " + s).getBytes());
        System.out.println("Echo enviado...");

    }

   public void sendMessage(String message) {

        this.device.send(message.getBytes());
        System.out.println("Enviado: "+message);
    }

    public void errorOnReceiving(IOException e) {
        System.err.println(e.getMessage());
    }

    public void errorOnSending(IOException e) {
        System.err.println(e.getMessage());
    }


     public void conecta(){

        conexao server = new conexao(new RFCOMMCommunicationFactory());
        server.startServer();
        
     }

}

alguém poderia me ajuda.

Muito Obrigado.

#2