Add XMPPConnection.addAsyncPacketListener(PacketListener, PacketFilter)

and use this method in packet listeners that previously used Async.go().

smack-core/src/main/java/org/jivesoftware/smack/AbstractXMPPConnection.java

@@ -131,6 +131,8 @@ public abstract class AbstractXMPPConnection implements XMPPConnection {
     private final Map<PacketListener, ListenerWrapper> recvListeners =
             new HashMap<PacketListener, ListenerWrapper>();
 
+    private final Map<PacketListener, ListenerWrapper> asyncRecvListeners = new HashMap<>();
+
     /**
      * List of PacketListeners that will be notified when a new packet was sent.
      */
@@ -741,6 +743,24 @@ public abstract class AbstractXMPPConnection implements XMPPConnection {
         }
     }
 
+    @Override
+    public void addAsyncPacketListener(PacketListener packetListener, PacketFilter packetFilter) {
+        if (packetListener == null) {
+            throw new NullPointerException("Packet listener is null.");
+        }
+        ListenerWrapper wrapper = new ListenerWrapper(packetListener, packetFilter);
+        synchronized (asyncRecvListeners) {
+            asyncRecvListeners.put(packetListener, wrapper);
+        }
+    }
+
+    @Override
+    public boolean removeAsyncPacketListener(PacketListener packetListener) {
+        synchronized (asyncRecvListeners) {
+            return asyncRecvListeners.remove(packetListener) != null;
+        }
+    }
+
     @Override
     public void addPacketSendingListener(PacketListener packetListener, PacketFilter packetFilter) {
         if (packetListener == null) {
@@ -937,14 +957,39 @@ public abstract class AbstractXMPPConnection implements XMPPConnection {
      *
      * @param packet the packet to notify the PacketCollectors and receive listeners about.
      */
-    protected void invokePacketCollectorsAndNotifyRecvListeners(Packet packet) {
+    protected void invokePacketCollectorsAndNotifyRecvListeners(final Packet packet) {
+        // First handle the async recv listeners. Note that this code is very similar to what follows a few lines below,
+        // the only difference is that asyncRecvListeners is used here and that the packet listeners are started in
+        // their own thread.
+        Collection<PacketListener> listenersToNotify = new LinkedList<PacketListener>();
+        synchronized (asyncRecvListeners) {
+            for (ListenerWrapper listenerWrapper : asyncRecvListeners.values()) {
+                if (listenerWrapper.filterMatches(packet)) {
+                    listenersToNotify.add(listenerWrapper.getListener());
+                }
+            }
+        }
+
+        for (final PacketListener listener : listenersToNotify) {
+            asyncGo(new Runnable() {
+                @Override
+                public void run() {
+                    try {
+                        listener.processPacket(packet);
+                    } catch (Exception e) {
+                        LOGGER.log(Level.SEVERE, "Exception in async packet listener", e);
+                    }
+                }
+            });
+        }
+
         // Loop through all collectors and notify the appropriate ones.
         for (PacketCollector collector: collectors) {
             collector.processPacket(packet);
         }
 
         // Notify the receive listeners interested in the packet
-        List<PacketListener> listenersToNotify = new LinkedList<PacketListener>();
+        listenersToNotify = new LinkedList<PacketListener>();
         synchronized (recvListeners) {
             for (ListenerWrapper listenerWrapper : recvListeners.values()) {
                 if (listenerWrapper.filterMatches(packet)) {

smack-core/src/main/java/org/jivesoftware/smack/XMPPConnection.java

@@ -266,6 +266,29 @@ public interface XMPPConnection {
      */
     public boolean removePacketListener(PacketListener packetListener);
 
+    /**
+     * Registers an <b>asynchronous</b> packet listener with this connection. A packet listener will be invoked only
+     * when an incoming packet is received. A packet filter determines which packets will be delivered to the listener.
+     * If the same packet listener is added again with a different filter, only the new filter will be used.
+     * <p>
+     * Unlike {@link #addPacketListener(PacketListener, PacketFilter)} packet listeners added with this method will be
+     * invoked asynchronously in their own thread. Use this method if the order of the packet listeners must not depend
+     * on the order how the stanzas where received.
+     * </p>
+     * 
+     * @param packetListener the packet listener to notify of new received packets.
+     * @param packetFilter the packet filter to use.
+     */
+    public void addAsyncPacketListener(PacketListener packetListener, PacketFilter packetFilter);
+
+    /**
+     * Removes an <b>asynchronous</b> packet listener for received packets from this connection.
+     * 
+     * @param packetListener the packet listener to remove.
+     * @return true if the packet listener was removed
+     */
+    public boolean removeAsyncPacketListener(PacketListener packetListener);
+
     /**
      * Registers a packet listener with this connection. The listener will be
      * notified of every packet that this connection sends. A packet filter determines

smack-extensions/src/main/java/org/jivesoftware/smackx/filetransfer/FileTransferManager.java

@@ -26,7 +26,6 @@ import org.jivesoftware.smack.filter.PacketTypeFilter;
 import org.jivesoftware.smack.packet.IQ;
 import org.jivesoftware.smack.packet.Packet;
 import org.jivesoftware.smack.packet.XMPPError;
-import org.jivesoftware.smack.util.Async;
 import org.jivesoftware.smackx.si.packet.StreamInitiation;
 import org.jxmpp.util.XmppStringUtils;
 
@@ -74,22 +73,13 @@ public class FileTransferManager extends Manager {
 		super(connection);
 		this.fileTransferNegotiator = FileTransferNegotiator
 				.getInstanceFor(connection);
-        connection.addPacketListener(new PacketListener() {
+        connection.addAsyncPacketListener(new PacketListener() {
             public void processPacket(Packet packet) {
                 StreamInitiation si = (StreamInitiation) packet;
                 final FileTransferRequest request = new FileTransferRequest(FileTransferManager.this, si);
                 for (final FileTransferListener listener : listeners) {
-                    // Those listeners need to be called asynchronously, in
-                    // order to not block further processing of incoming
-                    // stanzas. They also may send further requests, whose
-                    // responses are not processed if we do not call them
-                    // asynchronously.
-                    Async.go(new Runnable() {
-                        public void run() {
                             listener.fileTransferRequest(request);
                 }
-                    });
-                }
             }
         }, new AndFilter(new PacketTypeFilter(StreamInitiation.class), IQTypeFilter.SET));
 	}

smack-extensions/src/main/java/org/jivesoftware/smackx/muc/MultiUserChatManager.java

@@ -43,7 +43,6 @@ import org.jivesoftware.smack.filter.NotFilter;
 import org.jivesoftware.smack.filter.PacketTypeFilter;
 import org.jivesoftware.smack.packet.Message;
 import org.jivesoftware.smack.packet.Packet;
-import org.jivesoftware.smack.util.Async;
 import org.jivesoftware.smackx.disco.AbstractNodeInformationProvider;
 import org.jivesoftware.smackx.disco.ServiceDiscoveryManager;
 import org.jivesoftware.smackx.disco.packet.DiscoverInfo;
@@ -114,13 +113,11 @@ public class MultiUserChatManager extends Manager {
      */
     private final Map<String, WeakReference<MultiUserChat>> multiUserChats = new HashMap<String, WeakReference<MultiUserChat>>();
 
-    private final PacketListener invitationPacketListener;
-
     private MultiUserChatManager(XMPPConnection connection) {
         super(connection);
         // Listens for all messages that include a MUCUser extension and fire the invitation
         // listeners if the message includes an invitation.
-        invitationPacketListener = new PacketListener() {
+        PacketListener invitationPacketListener = new PacketListener() {
             public void processPacket(Packet packet) {
                 final Message message = (Message) packet;
                 // Get the MUCUser extension
@@ -130,18 +127,13 @@ public class MultiUserChatManager extends Manager {
                     // Fire event for invitation listeners
                     final MultiUserChat muc = getMultiUserChat(packet.getFrom());
                     for (final InvitationListener listener : invitationsListeners) {
-                        Async.go(new Runnable() {
-                            @Override
-                            public void run() {
                         listener.invitationReceived(connection(), muc, mucUser.getInvite().getFrom(),
                                         mucUser.getInvite().getReason(), mucUser.getPassword(), message);
                     }
-                        });
-                    }
                 }
             }
         };
-        connection.addPacketListener(invitationPacketListener, INVITATION_FILTER);
+        connection.addAsyncPacketListener(invitationPacketListener, INVITATION_FILTER);
     }
 
     /**