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Android app did not receive data from SignalR hub

I already read these topics:
how to use SignalR in Android
Android Client doesn't get data but .net client getting data from SignalR server
I write a simple chat system with Android that works with SignalR.
It is supposed to the clients send messages (by calling SendMessage method on the server) and the server should call the NewMessage method on the clients.
Here is my ChatHub class (simplified) written in C#.
public class ChatHub : Hub
{
// Store the clients connections Id
static readonly List<string> _connectedClients;
public override Task OnConnected()
{
// Keep connections id
// This section works fine and when the android device connects to the server,
// Its connection id will stored.
_connectedClients.Add(Context.ConnectionId)
//... other codes
}
public void SendMessage(string message)
{
foreach (var connectionId in _connectedClients)
{
// according to the logs
// android device connection id exists here
// and it works fine.
Clients.Client(connectionId).NewMessage(message);
}
}
}
When the android client connects to the server, On the OnConnected method, the connection id will be stored in the _connectedClients and it works fine.
In the SendMessage method of the ChatHub class, We have the android device connection id, and I'm sure that the android device is within the list
And here is my Andoird codes:
public class ChatActivity extends AppCompatActivity
{
// private fields
HubConnection connection;
HubProxy hub;
ClientTransport transport;
protected void onCreate(Bundle savedInstanceState) {
Logger logger = new Logger() {
#Override
public void log(String message, LogLevel logLevel) {
Log.e("SignalR", message);
}
};
Platform.loadPlatformComponent(new AndroidPlatformComponent());
connection = new HubConnection("192.168.1.100");
hub = connection.createHubProxy("chatHub"); // case insensitivity
transport = new LongPollingTransport(connection.getLogger());
// no difference when using this:
//transport = new ServerSentEventsTransport(connection.getLogger());
// this event never fired!
hub.subscribe(new Object() {
public void NewMessage(String message)
{
Log.d("<Debug", "new message received in subscribe"); // won't work!
}
}
// this event never fired!
hub.on("NewMessage", new SubscriptionHandler() {
#Override
public void run() {
Log.d("<Debug", "new message received in `on`"); // won't work!
}
});
// connect to the server that works fine.
SignalRFuture<Void> awaitConnection = connection.start(transport);
try {
awaitConnection.get(); // seems useless when using this or not!
}
catch (Exception ex) {
}
// this method works fine.
hub.invoke("sendMessage", "this is a test message to the server")
.done(new Action<Void>() {
#Override
public void run(Void aVoid) throws Exception {
Log.d("<Debug", "message sent."); // Works fine
}
});
}
}
In the above java code, invoking the sendMessage on the server works fine and the server get the messages.
But the only problem is that the hub.on(...) or hub.subscribe(...) events are never be called by the server.
In a simple description, My app can send message, but can not receive message from the others.
Any suggestion will be appreciated.

For the futures this is the way I finally achieved the answer (please first read the question android codes):
public class ChatActivity extends AppCompatActivity
{
// private fields
HubConnection connection;
HubProxy hub;
ClientTransport transport;
protected void onCreate(Bundle savedInstanceState) {
Logger logger = new Logger() {
#Override
public void log(String message, LogLevel logLevel) {
Log.e("SignalR", message);
}
};
Platform.loadPlatformComponent(new AndroidPlatformComponent());
connection = new HubConnection("192.168.1.100");
hub = connection.createHubProxy("chatHub"); // case insensitivity
/* ****new codes here**** */
hub.subscribe(this);
transport = new LongPollingTransport(connection.getLogger());
/* ****new codes here**** */
connection.start(transport);
/* ****new codes here**** */
/* ****seems useless but should be here!**** */
hub.subscribe(new Object() {
#SuppressWarnings("unused")
public void newMessage(final String message, final String messageId, final String chatId,
final String senderUserId, final String fileUrl, final String replyToMessageId) {
}
});
/* ********************** */
/* ****new codes here**** */
/* **** the main method that I fetch data from server**** */
connection.received(new MessageReceivedHandler() {
#Override
public void onMessageReceived(final JsonElement json) {
runOnUiThread(new Runnable() {
public void run() {
JsonObject jsonObject = json.getAsJsonObject();
Log.e("<Debug>", "response = " + jsonObject.toString());
}
});
}
});
/* ********************** */
}
}
!important note:
The priority of the codes is important. this is how I fix my problem in this topic.

You does not provider parameters in your client-side which should be same as your side-site. The code should be below:
hub.on("NewMessage", new SubscriptionHandler1<String>() {
#Override
public void run(String message) {
Log.d("<Debug", "new message received in `on`");
}
},String.class); //do not forget say the String class in the end

smack presence listener in multi user chat

smack presence listener in multi user chat not getting called. Used Smack Api to login and then added roster.addRosterListener(mRoasterListener); but could not get any success to listen when presence of other user of the chat room changes. I tried following code to get the presence listener to work :
connection.login(loginUser, passwordUser);
MultiUserChatManager manager =
MultiUserChatManager.getInstanceFor(connection);
muc = manager.getMultiUserChat(roomID + "#" +context.getString(R.string.group_chat_id));
Log.d("Join User: ", "Already Created");
muc.join(Utilities.getUserPhoneNo(context));
muc.addMessageListener(mGroupMessageListener);
Roster roster = Roster.getInstanceFor(connection);//luna
roster.addRosterListener(mRoasterListener);//roasterListener
Log.d("Joined User Phone: ", " " + Utilities.getUserPhoneNo(context));
and this class to listen for presence change...
public class RoasterListener implements RosterListener{
public RoasterListener(Context context){
}
#Override
public void entriesAdded(Collection<String> collection) {
}
#Override
public void entriesUpdated(Collection<String> collection) {
}
#Override
public void entriesDeleted(Collection<String> collection) {
}
#Override
public void presenceChanged(Presence presence) {
System.out.println("Presence changed: " + presence.getFrom() + " " + presence);
}
}
I tried many links available by stackoverflow but could not get any success.
Please Help!

For Multi User Chat you don't have to use Roster, because it's normal to meet people you don't have in Roster.
To know who is in a muc, first ask for occupants:
muc.join(user,password);
List<String> occupantsAtJoinTime = muc.getOccupants();
for (String occupant : occupantsAtJoinTime)
{
System.out.println("occupant: "+occupant);
//actions
}
then, to keep Occupants list updated, register a DefaultParticipantStatusListener to your muc and define that Listner:
muc.addParticipantStatusListener(new CustomParticipantStatusListner());
definied as (there are many methods to implement if you need):
public class CustomParticipantStatusListner extends DefaultParticipantStatusListener
{
public void joined(String participant)
{
System.out.println(participant + "just joined MUC");
//actions (add occupantsRightNow)
}
public void left(String participant)
{
System.out.println(participant + " just left MUC");
//actions (remove occupantsRightNow)
}
}
All this with smack 4.1.7

It's about the Manage role modifications in Multi User Chat.
This example shows how to grant voice to a visitor and listen for the notification events:
// User1 creates a room
muc = new MultiUserChat(conn1, "myroom#conference.jabber.org");
muc.create("testbot");
// User1 (which is the room owner) configures the room as a moderated room
Form form = muc.getConfigurationForm();
Form answerForm = form.createAnswerForm();
answerForm.setAnswer("muc#roomconfig_moderatedroom", "1");
muc.sendConfigurationForm(answerForm);
// User2 joins the new room (as a visitor)
MultiUserChat muc2 = new MultiUserChat(conn2, "myroom#conference.jabber.org");
muc2.join("testbot2");
// User2 will listen for his own "voice" notification events
muc2.addUserStatusListener(new DefaultUserStatusListener() {
public void voiceGranted() {
super.voiceGranted();
...
}
public void voiceRevoked() {
super.voiceRevoked();
...
}
});
// User3 joins the new room (as a visitor)
MultiUserChat muc3 = new MultiUserChat(conn3, "myroom#conference.jabber.org");
muc3.join("testbot3");
// User3 will lister for other occupants "voice" notification events
muc3.addParticipantStatusListener(new DefaultParticipantStatusListener() {
public void voiceGranted(String participant) {
super.voiceGranted(participant);
...
}
public void voiceRevoked(String participant) {
super.voiceRevoked(participant);
...
}
});
// The room's owner grants voice to user2
muc.grantVoice("testbot2");
Details can be refered in http://web.mit.edu/svalente/lib/smack_3_0_4/documentation/extensions/muc.html .

Firstly, join a chat room:
public MultiUserChat joinMultiUserChat(String user, String roomsName,
String password) {
if (getConnection() == null)
return null;
try {
MultiUserChat muc = new MultiUserChat(getConnection(), roomsName
+ "#conference." + getConnection().getServiceName());
DiscussionHistory history = new DiscussionHistory();
history.setMaxChars(0);
// history.setSince(new Date());
muc.join(user, password, history,
SmackConfiguration.getPacketReplyTimeout());
Log.i("MultiUserChat", "Chat room【"+roomsName+"】joined........");
return muc;
} catch (XMPPException e) {
e.printStackTrace();
Log.i("MultiUserChat", "Chat room【"+roomsName+"】failed........");
return null;
}
}
Then, use MultiChatUser to send Message:
try {
multiUserChat.sendMessage(message);
} catch (XMPPException e) {
e.printStackTrace();
}
Add a Listener:
import org.jivesoftware.smack.PacketListener;
import org.jivesoftware.smack.packet.Message;
import org.jivesoftware.smack.packet.Packet;
public class TaxiMultiListener implements PacketListener {
#Override
public void processPacket(Packet packet) {
Message message = (Message) packet;
String body = message.getBody();
}
}
Finally, call the Listener using MultiUserChat:
multiUserChat.addMessageListener(new TaxiMultiListener());

Play2.5 Java WebSockets

Play 2.5 Highlights states
Better control over WebSocket frames
The Play 2.5 WebSocket API gives you direct control over WebSocket frames. You can now send and receive binary, text, ping, pong and close frames. If you don’t want to worry about this level of detail, Play will still automatically convert your JSON or XML data into the right kind of frame.
However
https://www.playframework.com/documentation/2.5.x/JavaWebSockets has examples around LegacyWebSocket which is deprecated
What is the recommended API/pattern for Java WebSockets? Is using
LegacyWebSocket the only option for java websockets?
Are there any examples using new Message types ping/pong to implement a heartbeat?

The official documentation on this is disappointingly very sparse. Perhaps in Play 2.6 we'll see an update to this. However, I will provide an example below on how to configure a chat websocket in Play 2.5, just to help out those in need.
Setup
AController.java
#Inject
private Materializer materializer;
private ActorRef chatSocketRouter;
#Inject
public AController(#Named("chatSocketRouter") ActorRef chatInjectedActor) {
this.chatSocketRouter = chatInjectedActor;
}
// Make a chat websocket for a user
public WebSocket chatSocket() {
return WebSocket.Json.acceptOrResult(request -> {
String authToken = getAuthToken();
// Checking of token
if (authToken == null) {
return forbiddenResult("No [authToken] supplied.");
}
// Could we find the token in the database?
final AuthToken token = AuthToken.findByToken(authToken);
if (token == null) {
return forbiddenResult("Could not find [authToken] in DB. Login again.");
}
User user = token.getUser();
if (user == null) {
return forbiddenResult("You are not logged in to view this stream.");
}
Long userId = user.getId();
// Create a function to be run when we initialise a flow.
// A flow basically links actors together.
AbstractFunction1<ActorRef, Props> getWebSocketActor = new AbstractFunction1<ActorRef, Props>() {
#Override
public Props apply(ActorRef connectionProperties) {
// We use the ActorRef provided in the param above to make some properties.
// An ActorRef is a fancy word for thread reference.
// The WebSocketActor manages the web socket connection for one user.
// WebSocketActor.props() means "make one thread (from the WebSocketActor) and return the properties on how to reference it".
// The resulting Props basically state how to construct that thread.
Props properties = ChatSocketActor.props(connectionProperties, chatSocketRouter, userId);
// We can have many connections per user. So we need many ActorRefs (threads) per user. As you can see from the code below, we do exactly that. We have an object called
// chatSocketRouter which holds a Map of userIds -> connectionsThreads and we "tell"
// it a lightweight object (UserMessage) that is made up of this connecting user's ID and the connection.
// As stated above, Props are basically a way of describing an Actor, or dumbed-down, a thread.
// In this line, we are using the Props above to
// reference the ActorRef we've just created above
ActorRef anotherUserDevice = actorSystem.actorOf(properties);
// Create a lightweight object...
UserMessage routeThisUser = new UserMessage(userId, anotherUserDevice);
// ... to tell the thread that has our Map that we have a new connection
// from a user.
chatSocketRouter.tell(routeThisUser, ActorRef.noSender());
// We return the properties to the thread that will be managing this user's connection
return properties;
}
};
final Flow<JsonNode, JsonNode, ?> jsonNodeFlow =
ActorFlow.<JsonNode, JsonNode>actorRef(getWebSocketActor,
100,
OverflowStrategy.dropTail(),
actorSystem,
materializer).asJava();
final F.Either<Result, Flow<JsonNode, JsonNode, ?>> right = F.Either.Right(jsonNodeFlow);
return CompletableFuture.completedFuture(right);
});
}
// Return this whenever we want to reject a
// user from connecting to a websocket
private CompletionStage<F.Either<Result, Flow<JsonNode, JsonNode, ?>>> forbiddenResult(String msg) {
final Result forbidden = Results.forbidden(msg);
final F.Either<Result, Flow<JsonNode, JsonNode, ?>> left = F.Either.Left(forbidden);
return CompletableFuture.completedFuture(left);
}
ChatSocketActor.java
public class ChatSocketActor extends UntypedActor {
private final ActorRef out;
private final Long userId;
private ActorRef chatSocketRouter;
public ChatSocketActor(ActorRef out, ActorRef chatSocketRouter, Long userId) {
this.out = out;
this.userId = userId;
this.chatSocketRouter = chatSocketRouter;
}
public static Props props(ActorRef out, ActorRef chatSocketRouter, Long userId) {
return Props.create(ChatSocketActor.class, out, chatSocketRouter, userId);
}
// Add methods here handling each chat connection...
}
ChatSocketRouter.java
public class ChatSocketRouter extends UntypedActor {
public ChatSocketRouter() {}
// Stores userIds to websockets
private final HashMap<Long, List<ActorRef>> senders = new HashMap<>();
private void addSender(Long userId, ActorRef actorRef){
if (senders.containsKey(userId)) {
final List<ActorRef> actors = senders.get(userId);
actors.add(actorRef);
senders.replace(userId, actors);
} else {
List<ActorRef> l = new ArrayList<>();
l.add(actorRef);
senders.put(userId, l);
}
}
private void removeSender(ActorRef actorRef){
for (List<ActorRef> refs : senders.values()) {
refs.remove(actorRef);
}
}
#Override
public void onReceive(Object message) throws Exception {
ActorRef sender = getSender();
// Handle messages sent to this 'router' here
if (message instanceof UserMessage) {
UserMessage userMessage = (UserMessage) message;
addSender(userMessage.userId, userMessage.actorRef);
// Watch sender so we can detect when they die.
getContext().watch(sender);
} else if (message instanceof Terminated) {
// One of our watched senders has died.
removeSender(sender);
} else {
unhandled(message);
}
}
}
Example
Now whenever you want to send a client with a websocket connection a message you can do something like:
ChatSenderController.java
private ActorRef chatSocketRouter;
#Inject
public ChatSenderController(#Named("chatSocketRouter") ActorRef chatInjectedActor) {
this.chatSocketRouter = chatInjectedActor;
}
public static void sendMessage(Long sendToId) {
// E.g. send the chat router a message that says hi
chatSocketRouter.tell(new Message(sendToId, "Hi"));
}
ChatSocketRouter.java
#Override
public void onReceive(Object message) throws Exception {
// ...
if (message instanceof Message) {
Message messageToSend = (Message) message;
// Loop through the list above and send the message to
// each connection. For example...
for (ActorRef wsConnection : senders.get(messageToSend.getSendToId())) {
// Send "Hi" to each of the other client's
// connected sessions
wsConnection.tell(messageToSend.getMessage());
}
}
// ...
}
Again, I wrote the above to help out those in need. After scouring the web I could not find a reasonable and simple example. There is an open issue for this exact topic. There are also some examples online but none of them were easy to follow. Akka has some great documentation but mixing it in with Play was a tough mental task.
Please help improve this answer if you see anything that is amiss.

Alljoyn framework - Java - Signals . BUS_NO_SUCH_INTERFACE

It's a quite specific question but after days stuck in the same place and not getting any response in the Alljoyn forum, I decided to post it here. Maybe someone worked with this framework.
I am doing a project and I need the use of the signal mechanish that Alljoyn framework provides. However, I do need the signals inside a session and the example provides in the api core is sessionless.
In my case I need the service (server) to raise a signal and the client to receive it, but I am getting this error. Following the api samples, I managed to create a simple app that exchange messages through the methods defined in the interface, so I know that the communication is working. In this case, the service waits until the client connects and the send the signal. The client joins the session and right after register the signal and I am getting the BUS_NO_SUCH_INTERFACE error. I tried also to register after and before sending the signal, same problem. I think that for some reason the client does not find the bussignalhandler but I don't know why. I also put it in an external class and it didn't work.
I'm following the example in the core api guide:
https://allseenalliance.org/developers/develop/api-guide/core/android
This is the part where the service register and emit the signal:
SignalEmitter emitter = new SignalEmitter(mySignalInterface, joinerName,
sessionId,
SignalEmitter.GlobalBroadcast.Off);
myInterface = emitter.getInterface(SampleInterface.class);
// Emitting signals myInterface.buttonClicked(1);
myInterface.playerPosition(12, 1, -24);
However, in that example, I can't see a definition for myInterface. and I know it is not a mistake and they meant mySignalInterface because the method getInterface asks for an interface object and mySignalInterface is a class which implements that interface.
I put here the example I created and I'll upload the files in case someone wants to try them.
#BusInterface(name = "org.alljoyn.bus.samples.simple.SimpleInterface")
public interface SimpleInterface {
#BusMethod
String Ping(String inStr) throws BusException;
#BusSignal
public void playerPosition(int x, int y, int z) throws BusException;
}
Service:
Class inside the service to implement the signal and method
class SimpleService implements SimpleInterface, BusObject {
public String Ping(String inStr) {
mHandler.sendMessage(mHandler.obtainMessage(MESSAGE_PING, inStr));
return inStr;
}
public void playerPosition(int x, int y, int z) { /* no implementation needed here*/}
}
Here part of the code that makes the connection in the service:
case CONNECT: {
org.alljoyn.bus.alljoyn.DaemonInit.PrepareDaemon(getApplicationContext());
mBus = new BusAttachment(getPackageName(), BusAttachment.RemoteMessage.Receive);
mBus.registerBusListener(new BusListener());
Status status = mBus.registerBusObject(mSimpleService, "/SimpleService");
if (status != Status.OK) {...}
status = mBus.connect();
logStatus("BusAttachment.connect()", status);
if (status != Status.OK) {...}
int flag = 0;
status = mBus.requestName(SERVICE_NAME, flag);
logStatus(String.format("BusAttachment.requestName(%s, 0x%08x)", SERVICE_NAME, flag), status);
if (status == Status.OK) {
status = mBus.advertiseName(SERVICE_NAME, SessionOpts.TRANSPORT_ANY);
logStatus(String.format("BusAttachement.advertiseName(%s)", SERVICE_NAME), status);
if (status != Status.OK) {...}
}
Mutable.ShortValue contactPort = new Mutable.ShortValue(CONTACT_PORT);
SessionOpts sessionOpts = new SessionOpts();
sessionOpts.traffic = SessionOpts.TRAFFIC_MESSAGES;
sessionOpts.isMultipoint = false;
sessionOpts.proximity = SessionOpts.PROXIMITY_ANY;
sessionOpts.transports = SessionOpts.TRANSPORT_ANY + SessionOpts.TRANSPORT_WFD;
status = mBus.bindSessionPort(contactPort, sessionOpts, new SessionPortListener() {
#Override
public boolean acceptSessionJoiner(short sessionPort, String joiner, SessionOpts sessionOpts) {
return sessionPort == CONTACT_PORT;
}
#Override
public void sessionJoined(short port, int id, String s) {
sessionId = id; joinerName = s; sessionEstablished = true;
}
});
logStatus(String.format("BusAttachment.bindSessionPort(%d, %s)",
contactPort.value, sessionOpts.toString()), status);
if (status != Status.OK) {...}
try {
while (!sessionEstablished) {
Thread.sleep(10);
}
SignalEmitter emitter = new SignalEmitter(mSimpleService, joinerName, sessionId, SignalEmitter.GlobalBroadcast.Off);
SimpleInterface myInterface = emitter.getInterface(SimpleInterface.class);
myInterface.playerPosition(12,1,1);
}
catch (BusException ex) {... }
}
Client:
/*On create of the activity which has a button and a text view to send text to the server */
mEditText.setOnEditorActionListener(new TextView.OnEditorActionListener() {
public boolean onEditorAction(TextView view, int actionId, KeyEvent event) {
if (actionId == EditorInfo.IME_NULL
&& event.getAction() == KeyEvent.ACTION_UP) {
/* Call the remote object's Ping method. */
Message msg = mBusHandler.obtainMessage(BusHandler.PING,
view.getText().toString());
mBusHandler.sendMessage(msg);
}
return true;
}
});
private static final String SERVICE_NAME = "org.alljoyn.bus.samples.simple";
private static final short CONTACT_PORT=42;
private BusAttachment mBus;
private ProxyBusObject mProxyObj;
private SimpleInterface mSimpleInterface;
case CONNECT: {
org.alljoyn.bus.alljoyn.DaemonInit.PrepareDaemon(getApplicationContext());
mBus = new BusAttachment(getPackageName(), BusAttachment.RemoteMessage.Receive);
mBus.registerBusListener(new BusListener() {
#Override
public void foundAdvertisedName(String name, short transport, String namePrefix) {
if(!mIsConnected) {
Message msg = obtainMessage(JOIN_SESSION);
msg.arg1 = transport;
msg.obj = name;
sendMessage(msg);
}
}
});
Status status = mBus.connect();
logStatus("BusAttachment.connect()", status);
if (Status.OK != status) {...}
status = mBus.findAdvertisedName(SERVICE_NAME);
logStatus(String.format("BusAttachement.findAdvertisedName(%s)", SERVICE_NAME), status);
if (Status.OK != status) {...}
break;
}
case (JOIN_SESSION): {
if (mIsStoppingDiscovery) {
break;
}
short contactPort = CONTACT_PORT;
SessionOpts sessionOpts = new SessionOpts();
sessionOpts.transports = (short)msg.arg1;
Mutable.IntegerValue sessionId = new Mutable.IntegerValue();
Status status = mBus.joinSession((String) msg.obj, contactPort, sessionId, sessionOpts, new SessionListener() {
#Override
public void sessionLost(int sessionId, int reason) {
mIsConnected = false;
logInfo(String.format("MyBusListener.sessionLost(sessionId = %d, reason = %d)", sessionId,reason));
mHandler.sendEmptyMessage(MESSAGE_START_PROGRESS_DIALOG);
}
});
if (status == Status.OK) {
mProxyObj = mBus.getProxyBusObject(SERVICE_NAME,
"/SimpleService",
sessionId.value,
new Class<?>[] { SimpleInterface.class });
mSimpleInterface = mProxyObj.getInterface(SimpleInterface.class);
mSessionId = sessionId.value;
mIsConnected = true;
mHandler.sendEmptyMessage(MESSAGE_STOP_PROGRESS_DIALOG);
}
break;
status = mBus.registerSignalHandlers(this);
if (status != Status.OK) {...}
}
case PING: {
try {
if (mSimpleInterface != null) {
sendUiMessage(MESSAGE_PING, msg.obj);
String reply = mSimpleInterface.Ping((String) msg.obj);
sendUiMessage(MESSAGE_PING_REPLY, reply);
} catch {...}
}
...here some more code...
#BusSignalHandler(iface="org.alljoyn.bus.samples.simple.SimpleInterface", signal="playerPosition")
public void playerPosition(int x, int y, int z) {
sendUiMessage(MESSAGE_POST_TOAST, "Signal captured");
}
In this example, I have my client which has a textview where I can add text and send a ping to the server. This is working if I get rid of the registering signal part. I tried to do it as the api core says, with the Thread.sleep but doesn't work either.
Here I add the code of both of my applications (client & server) based on the samples that are in the alljoyn api.
https://github.com/JavierT/Alljoyn_signal_sample
Please let me know if you have some doubts, it was hard to put all the information in one post.
Thank you in advance.

I think this should solve your problem
Alljoyn BusSignalHandler
either of the following may be used to annotate a signal handler:
#BusSignalHandler(iface = "org.sample.MyInterface", signal = "MySignal")
public void handleSignal(String str)
{
}
#BusSignalHandler(iface = "org.myapp.IMyInterface", signal = "EmitMySignal")
public void handleSignal(String str)
{
}
The first example may be used succesfully when IMyInterface is known to the BusAttachment via a previous call to BusAttachment.registerBusObject(BusObject, String) or BusAttachment.getProxyBusObject(String, String, int, Class[]).
The second example may be used succesfully when IMyInterface is unknown to the BusAttachment.
using the second example should solve your problem.
Also, in your Client program as per the link provided above,
#BusSignalHandler(iface="org.alljoyn.bus.samples.simple.SimpleInterface", signal="playerPosition")
should be replaced with
#BusSignalHandler(iface="org.alljoyn.bus.samples.simpleclient.SimpleInterface", signal="playerPosition")

When you call registerSignalHandlers you must pass an object that implements the interface SimpleInterface and the method playerPosition will be called in that object when you receives a signal.
I believe (I've read the code quickly, I hope I'm not wrong) that you pass your BusHandler object, which does not implements SimpleInterface.

Please change :
private static final String SERVICE_NAME = "org.alljoyn.bus.samples.simple";
to
"org.alljoyn.bus.samples.simple.SimpleInterface" as you have interface name ,
both should be same . as when the Get method of BusObject is called the interface names does not match.

How Can I create,send and receive iq packets using smack(java)

I am connected to server(Xmpp)
but unable to send and receive packets at my psi client
Here is snippet of my code
POSClientIQ posclientiq = new POSClientIQ();
posclientiq.connectXMPPServer();
posclientiq.processMessage();
}
public void processMessage()
{ try{
final IQ iq1 = new IQ() {
public String getChildElementXML() {
return "<iq type='get' from ='sam'><query xmlns='jabber:iq:roster'></query></iq>";
}
};
iq1.setType(IQ.Type.GET);
// PacketCollector collector = connection.createPacketCollector(new PacketIDFilter(iq1.getPacketID()));
connection.sendPacket(iq1);
System.out.println("Message send");

The getChildElementXML() returns the tag. If you are using Smack then you don't need to write your own IQ implementation unless it is a custom query. For your case, to query the roster use RosterPacket.

If you have a custom query and you would like to use your IQ implementation then:
final IQ iq = new IQ() {
public String getChildElementXML() {
return "<query xmlns='http://jabber.org/protocol/disco#info'/>"; // here is your query
//this returns "<iq type='get' from='User#YourServer/Resource' id='info1'> <query xmlns='http://jabber.org/protocol/disco#info'/></iq>";
}};
// set the type
iq.setType(IQ.Type.GET);
// send the request
connection.sendPacket(iq);
As you can see you have here your custom query and you use Smack to set the rest of your IQ e.g. setting the type. Please note that Smack fills the "from" for you based on the JID your are logged into.

//To retrieve archive msges from server..
MyCustomIQ iq = new MyCustomIQ();
iq.setType(IQ.Type.set);
mConnection.sendIqWithResponseCallback(iq, new PacketListener() {
#Override
public void processPacket(Packet packet) throws SmackException.NotConnectedException {
Log.i("Send IQ with Response", "****** message " + packet);
}
}, new ExceptionCallback() {
#Override
public void processException(Exception exception) {
exception.printStackTrace();
Log.i("IO archjieve Exception",""+ exception.getMessage());
}
}, 5000);
mConnection.sendPacket(new Presence(Presence.Type.available));
PacketTypeFilter filter=new PacketTypeFilter(org.jivesoftware.smack.packet.Message.class);
PacketListener myListener=new PacketListener(){
public void processPacket(Packet packet){
if(((Message) packet).getType().equals(Message.Type.chat))
{
((Message) packet).getBody();
}
else if(((Message) packet).getType().equals(Message.Type.normal))
{
DefaultPacketExtension pacExten=PacketUtil.packetExtensionfromCollection(packet.getExtensions(), "result", "urn:xmpp:mam:0");
String strMsg=pacExten.getValue("body");
}
}
}
;
mConnection.addPacketListener(myListener, filter);
//My Custom IQ
class MyCustomIQ extends IQ {
String token;
protected MyCustomIQ() {
super("query","urn:xmpp:mam:0");
}
#Override
protected IQChildElementXmlStringBuilder getIQChildElementBuilder(IQChildElementXmlStringBuilder xml) {
// String queryId = prefix + Long.toString(new AtomicLong().incrementAndGet());
xml.attribute("queryid",queryId);
xml.rightAngleBracket();
return xml;
}
}
//You may get the response in PacketListerener sometimes so put debug in that also