001/**
002 *
003 * Copyright 2003-2007 Jive Software. 2020-2022 Florian Schmaus
004 *
005 * Licensed under the Apache License, Version 2.0 (the "License");
006 * you may not use this file except in compliance with the License.
007 * You may obtain a copy of the License at
008 *
009 *     http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017
018package org.jivesoftware.smackx.muc;
019
020import java.util.ArrayList;
021import java.util.Collection;
022import java.util.List;
023import java.util.Map;
024import java.util.Set;
025import java.util.concurrent.ConcurrentHashMap;
026import java.util.concurrent.CopyOnWriteArrayList;
027import java.util.concurrent.CopyOnWriteArraySet;
028import java.util.concurrent.atomic.AtomicInteger;
029import java.util.logging.Level;
030import java.util.logging.Logger;
031
032import org.jivesoftware.smack.MessageListener;
033import org.jivesoftware.smack.PresenceListener;
034import org.jivesoftware.smack.SmackException;
035import org.jivesoftware.smack.SmackException.NoResponseException;
036import org.jivesoftware.smack.SmackException.NotConnectedException;
037import org.jivesoftware.smack.StanzaCollector;
038import org.jivesoftware.smack.StanzaListener;
039import org.jivesoftware.smack.XMPPConnection;
040import org.jivesoftware.smack.XMPPException;
041import org.jivesoftware.smack.XMPPException.XMPPErrorException;
042import org.jivesoftware.smack.chat.ChatMessageListener;
043import org.jivesoftware.smack.filter.AndFilter;
044import org.jivesoftware.smack.filter.FromMatchesFilter;
045import org.jivesoftware.smack.filter.MessageTypeFilter;
046import org.jivesoftware.smack.filter.MessageWithBodiesFilter;
047import org.jivesoftware.smack.filter.MessageWithSubjectFilter;
048import org.jivesoftware.smack.filter.MessageWithThreadFilter;
049import org.jivesoftware.smack.filter.NotFilter;
050import org.jivesoftware.smack.filter.OrFilter;
051import org.jivesoftware.smack.filter.PossibleFromTypeFilter;
052import org.jivesoftware.smack.filter.PresenceTypeFilter;
053import org.jivesoftware.smack.filter.StanzaExtensionFilter;
054import org.jivesoftware.smack.filter.StanzaFilter;
055import org.jivesoftware.smack.filter.StanzaIdFilter;
056import org.jivesoftware.smack.filter.StanzaTypeFilter;
057import org.jivesoftware.smack.filter.ToMatchesFilter;
058import org.jivesoftware.smack.packet.IQ;
059import org.jivesoftware.smack.packet.Message;
060import org.jivesoftware.smack.packet.MessageBuilder;
061import org.jivesoftware.smack.packet.MessageView;
062import org.jivesoftware.smack.packet.Presence;
063import org.jivesoftware.smack.packet.PresenceBuilder;
064import org.jivesoftware.smack.packet.Stanza;
065import org.jivesoftware.smack.util.Consumer;
066import org.jivesoftware.smack.util.Objects;
067
068import org.jivesoftware.smackx.disco.ServiceDiscoveryManager;
069import org.jivesoftware.smackx.disco.packet.DiscoverInfo;
070import org.jivesoftware.smackx.iqregister.packet.Registration;
071import org.jivesoftware.smackx.muc.MultiUserChatException.MissingMucCreationAcknowledgeException;
072import org.jivesoftware.smackx.muc.MultiUserChatException.MucAlreadyJoinedException;
073import org.jivesoftware.smackx.muc.MultiUserChatException.MucNotJoinedException;
074import org.jivesoftware.smackx.muc.MultiUserChatException.NotAMucServiceException;
075import org.jivesoftware.smackx.muc.filter.MUCUserStatusCodeFilter;
076import org.jivesoftware.smackx.muc.packet.Destroy;
077import org.jivesoftware.smackx.muc.packet.MUCAdmin;
078import org.jivesoftware.smackx.muc.packet.MUCInitialPresence;
079import org.jivesoftware.smackx.muc.packet.MUCItem;
080import org.jivesoftware.smackx.muc.packet.MUCOwner;
081import org.jivesoftware.smackx.muc.packet.MUCUser;
082import org.jivesoftware.smackx.muc.packet.MUCUser.Status;
083import org.jivesoftware.smackx.xdata.FormField;
084import org.jivesoftware.smackx.xdata.TextSingleFormField;
085import org.jivesoftware.smackx.xdata.form.FillableForm;
086import org.jivesoftware.smackx.xdata.form.Form;
087import org.jivesoftware.smackx.xdata.packet.DataForm;
088
089import org.jxmpp.jid.DomainBareJid;
090import org.jxmpp.jid.EntityBareJid;
091import org.jxmpp.jid.EntityFullJid;
092import org.jxmpp.jid.EntityJid;
093import org.jxmpp.jid.Jid;
094import org.jxmpp.jid.impl.JidCreate;
095import org.jxmpp.jid.parts.Resourcepart;
096
097/**
098 * A MultiUserChat room (XEP-45), created with {@link MultiUserChatManager#getMultiUserChat(EntityBareJid)}.
099 * <p>
100 * A MultiUserChat is a conversation that takes place among many users in a virtual
101 * room. A room could have many occupants with different affiliation and roles.
102 * Possible affiliations are "owner", "admin", "member", and "outcast". Possible roles
103 * are "moderator", "participant", and "visitor". Each role and affiliation guarantees
104 * different privileges (e.g. Send messages to all occupants, Kick participants and visitors,
105 * Grant voice, Edit member list, etc.).
106 * </p>
107 * <p>
108 * <b>Note:</b> Make sure to leave the MUC ({@link #leave()}) when you don't need it anymore or
109 * otherwise you may leak the instance.
110 * </p>
111 *
112 * @author Gaston Dombiak
113 * @author Larry Kirschner
114 * @author Florian Schmaus
115 */
116public class MultiUserChat {
117    private static final Logger LOGGER = Logger.getLogger(MultiUserChat.class.getName());
118
119    private final XMPPConnection connection;
120    private final EntityBareJid room;
121    private final MultiUserChatManager multiUserChatManager;
122    private final Map<EntityFullJid, Presence> occupantsMap = new ConcurrentHashMap<>();
123
124    private final Set<InvitationRejectionListener> invitationRejectionListeners = new CopyOnWriteArraySet<InvitationRejectionListener>();
125    private final Set<SubjectUpdatedListener> subjectUpdatedListeners = new CopyOnWriteArraySet<SubjectUpdatedListener>();
126    private final Set<UserStatusListener> userStatusListeners = new CopyOnWriteArraySet<UserStatusListener>();
127    private final Set<ParticipantStatusListener> participantStatusListeners = new CopyOnWriteArraySet<ParticipantStatusListener>();
128    private final Set<MessageListener> messageListeners = new CopyOnWriteArraySet<MessageListener>();
129    private final Set<PresenceListener> presenceListeners = new CopyOnWriteArraySet<PresenceListener>();
130    private final Set<Consumer<PresenceBuilder>> presenceInterceptors = new CopyOnWriteArraySet<>();
131
132    /**
133     * This filter will match all stanzas send from the groupchat or from one if
134     * the groupchat participants, i.e. it filters only the bare JID of the from
135     * attribute against the JID of the MUC.
136     */
137    private final StanzaFilter fromRoomFilter;
138
139    /**
140     * Same as {@link #fromRoomFilter} together with {@link MessageTypeFilter#GROUPCHAT}.
141     */
142    private final StanzaFilter fromRoomGroupchatFilter;
143
144    private final AtomicInteger presenceInterceptorCount = new AtomicInteger();
145    // We want to save the presence interceptor in a variable, using a lambda, (and not use a method reference) to be
146    // able to dynamically add and remove it from the connection.
147    @SuppressWarnings("UnnecessaryLambda")
148    private final Consumer<PresenceBuilder> presenceInterceptor = presenceBuilder -> {
149        for (Consumer<PresenceBuilder> interceptor : presenceInterceptors) {
150            interceptor.accept(presenceBuilder);
151        }
152    };
153
154    private final StanzaListener messageListener;
155    private final StanzaListener presenceListener;
156    private final StanzaListener subjectListener;
157
158    private static final StanzaFilter DECLINE_FILTER = new AndFilter(MessageTypeFilter.NORMAL,
159                    new StanzaExtensionFilter(MUCUser.ELEMENT, MUCUser.NAMESPACE));
160    private final StanzaListener declinesListener;
161
162    private String subject;
163    private EntityFullJid myRoomJid;
164    private StanzaCollector messageCollector;
165
166    private DiscoverInfo mucServiceDiscoInfo;
167
168    /**
169     * Used to signal that the reflected self-presence was received <b>and</b> processed by us.
170     */
171    private volatile boolean processedReflectedSelfPresence;
172
173    private CopyOnWriteArrayList<MucMessageInterceptor> messageInterceptors;
174
175    MultiUserChat(XMPPConnection connection, EntityBareJid room, MultiUserChatManager multiUserChatManager) {
176        this.connection = connection;
177        this.room = room;
178        this.multiUserChatManager = multiUserChatManager;
179        this.messageInterceptors = MultiUserChatManager.getMessageInterceptors();
180
181        fromRoomFilter = FromMatchesFilter.create(room);
182        fromRoomGroupchatFilter = new AndFilter(fromRoomFilter, MessageTypeFilter.GROUPCHAT);
183
184        messageListener = new StanzaListener() {
185            @Override
186            public void processStanza(Stanza packet) throws NotConnectedException {
187                final Message message = (Message) packet;
188
189                for (MessageListener listener : messageListeners) {
190                            listener.processMessage(message);
191                }
192            }
193        };
194
195        // Create a listener for subject updates.
196        subjectListener = new StanzaListener() {
197            @Override
198            public void processStanza(Stanza packet) {
199                final Message msg = (Message) packet;
200                final EntityFullJid from = msg.getFrom().asEntityFullJidIfPossible();
201                // Update the room subject
202                subject = msg.getSubject();
203
204                // Fire event for subject updated listeners
205                for (SubjectUpdatedListener listener : subjectUpdatedListeners) {
206                    listener.subjectUpdated(msg.getSubject(), from);
207                }
208            }
209        };
210
211        // Create a listener for all presence updates.
212        presenceListener = new StanzaListener() {
213            @Override
214            public void processStanza(final Stanza packet) {
215                final Presence presence = (Presence) packet;
216                final EntityFullJid from = presence.getFrom().asEntityFullJidIfPossible();
217                if (from == null) {
218                    return;
219                }
220                final EntityFullJid myRoomJID = getMyRoomJid();
221                final boolean isUserStatusModification = presence.getFrom().equals(myRoomJID);
222                final MUCUser mucUser = MUCUser.from(packet);
223
224                switch (presence.getType()) {
225                case available:
226                    if (!processedReflectedSelfPresence
227                                    && mucUser.getStatus().contains(MUCUser.Status.PRESENCE_TO_SELF_110)) {
228                        processedReflectedSelfPresence = true;
229                        synchronized (this) {
230                            notify();
231                        }
232                    }
233
234                    Presence oldPresence = occupantsMap.put(from, presence);
235                    if (oldPresence != null) {
236                        // Get the previous occupant's affiliation & role
237                        MUCUser mucExtension = MUCUser.from(oldPresence);
238                        MUCAffiliation oldAffiliation = mucExtension.getItem().getAffiliation();
239                        MUCRole oldRole = mucExtension.getItem().getRole();
240                        // Get the new occupant's affiliation & role
241                        MUCAffiliation newAffiliation = mucUser.getItem().getAffiliation();
242                        MUCRole newRole = mucUser.getItem().getRole();
243                        // Fire role modification events
244                        checkRoleModifications(oldRole, newRole, isUserStatusModification, from);
245                        // Fire affiliation modification events
246                        checkAffiliationModifications(
247                            oldAffiliation,
248                            newAffiliation,
249                            isUserStatusModification,
250                            from);
251                    } else {
252                        // A new occupant has joined the room
253                        for (ParticipantStatusListener listener : participantStatusListeners) {
254                            listener.joined(from);
255                        }
256                    }
257                    break;
258                case unavailable:
259                    occupantsMap.remove(from);
260                    if (mucUser != null && mucUser.hasStatus()) {
261                        if (isUserStatusModification) {
262                            userHasLeft();
263                        }
264                        // Fire events according to the received presence code
265                        checkPresenceCode(
266                            mucUser.getStatus(),
267                            isUserStatusModification,
268                            mucUser,
269                            from);
270                    } else {
271                        // An occupant has left the room
272                        if (!isUserStatusModification) {
273                            for (ParticipantStatusListener listener : participantStatusListeners) {
274                                listener.left(from);
275                            }
276                        }
277                    }
278
279                    Destroy destroy = mucUser.getDestroy();
280                    // The room has been destroyed.
281                    if (destroy != null) {
282                        EntityBareJid alternateMucJid = destroy.getJid();
283                        final MultiUserChat alternateMuc;
284                        if (alternateMucJid == null) {
285                            alternateMuc = null;
286                        } else {
287                            alternateMuc = multiUserChatManager.getMultiUserChat(alternateMucJid);
288                        }
289
290                        for (UserStatusListener listener : userStatusListeners) {
291                            listener.roomDestroyed(alternateMuc, destroy.getReason());
292                        }
293                    }
294
295                    if (isUserStatusModification) {
296                        for (UserStatusListener listener : userStatusListeners) {
297                            listener.removed(mucUser, presence);
298                        }
299                    } else {
300                        for (ParticipantStatusListener listener : participantStatusListeners) {
301                            listener.parted(from);
302                        }
303                    }
304                    break;
305                default:
306                    break;
307                }
308                for (PresenceListener listener : presenceListeners) {
309                    listener.processPresence(presence);
310                }
311            }
312        };
313
314        // Listens for all messages that include a MUCUser extension and fire the invitation
315        // rejection listeners if the message includes an invitation rejection.
316        declinesListener = new StanzaListener() {
317            @Override
318            public void processStanza(Stanza packet) {
319                Message message = (Message) packet;
320                // Get the MUC User extension
321                MUCUser mucUser = MUCUser.from(packet);
322                MUCUser.Decline rejection = mucUser.getDecline();
323                // Check if the MUCUser informs that the invitee has declined the invitation
324                if (rejection == null) {
325                    return;
326                }
327                // Fire event for invitation rejection listeners
328                fireInvitationRejectionListeners(message, rejection);
329            }
330        };
331    }
332
333
334    /**
335     * Returns the name of the room this MultiUserChat object represents.
336     *
337     * @return the multi user chat room name.
338     */
339    public EntityBareJid getRoom() {
340        return room;
341    }
342
343    /**
344     * Enter a room, as described in XEP-45 7.2.
345     *
346     * @param conf the configuration used to enter the room.
347     * @return the returned presence by the service after the client send the initial presence in order to enter the room.
348     * @throws NotConnectedException if the XMPP connection is not connected.
349     * @throws NoResponseException if there was no response from the remote entity.
350     * @throws XMPPErrorException if there was an XMPP error returned.
351     * @throws InterruptedException if the calling thread was interrupted.
352     * @throws NotAMucServiceException if the entity is not a MUC serivce.
353     * @see <a href="http://xmpp.org/extensions/xep-0045.html#enter">XEP-45 7.2 Entering a Room</a>
354     */
355    private Presence enter(MucEnterConfiguration conf) throws NotConnectedException, NoResponseException,
356                    XMPPErrorException, InterruptedException, NotAMucServiceException {
357        final DomainBareJid mucService = room.asDomainBareJid();
358        mucServiceDiscoInfo = multiUserChatManager.getMucServiceDiscoInfo(mucService);
359        if (mucServiceDiscoInfo == null) {
360            throw new NotAMucServiceException(this);
361        }
362        // We enter a room by sending a presence packet where the "to"
363        // field is in the form "roomName@service/nickname"
364        Presence joinPresence = conf.getJoinPresence(this);
365
366        // Setup the messageListeners and presenceListeners *before* the join presence is send.
367        connection.addStanzaListener(messageListener, fromRoomGroupchatFilter);
368        StanzaFilter presenceFromRoomFilter = new AndFilter(fromRoomFilter,
369                        StanzaTypeFilter.PRESENCE,
370                        PossibleFromTypeFilter.ENTITY_FULL_JID);
371        connection.addStanzaListener(presenceListener, presenceFromRoomFilter);
372        // @formatter:off
373        connection.addStanzaListener(subjectListener,
374                        new AndFilter(fromRoomFilter,
375                                      MessageWithSubjectFilter.INSTANCE,
376                                      new NotFilter(MessageTypeFilter.ERROR),
377                                      // According to XEP-0045 § 8.1 "A message with a <subject/> and a <body/> or a <subject/> and a <thread/> is a
378                                      // legitimate message, but it SHALL NOT be interpreted as a subject change."
379                                      new NotFilter(MessageWithBodiesFilter.INSTANCE),
380                                      new NotFilter(MessageWithThreadFilter.INSTANCE))
381                        );
382        // @formatter:on
383        connection.addStanzaListener(declinesListener, new AndFilter(fromRoomFilter, DECLINE_FILTER));
384        messageCollector = connection.createStanzaCollector(fromRoomGroupchatFilter);
385
386        // Wait for a presence packet back from the server.
387        // @formatter:off
388        StanzaFilter responseFilter = new AndFilter(StanzaTypeFilter.PRESENCE,
389                        new OrFilter(
390                            // We use a bare JID filter for positive responses, since the MUC service/room may rewrite the nickname.
391                            new AndFilter(FromMatchesFilter.createBare(getRoom()), MUCUserStatusCodeFilter.STATUS_110_PRESENCE_TO_SELF),
392                            // In case there is an error reply, we match on an error presence with the same stanza id and from the full
393                            // JID we send the join presence to.
394                            new AndFilter(FromMatchesFilter.createFull(joinPresence.getTo()), new StanzaIdFilter(joinPresence), PresenceTypeFilter.ERROR)
395                        )
396                    );
397        // @formatter:on
398        processedReflectedSelfPresence = false;
399        StanzaCollector presenceStanzaCollector = null;
400        final Presence reflectedSelfPresence;
401        try {
402            // This stanza collector will collect the final self presence from the MUC, which also signals that we have successful entered the MUC.
403            StanzaCollector selfPresenceCollector = connection.createStanzaCollectorAndSend(responseFilter, joinPresence);
404            StanzaCollector.Configuration presenceStanzaCollectorConfguration = StanzaCollector.newConfiguration().setCollectorToReset(
405                            selfPresenceCollector).setStanzaFilter(presenceFromRoomFilter);
406            // This stanza collector is used to reset the timeout of the selfPresenceCollector.
407            presenceStanzaCollector = connection.createStanzaCollector(presenceStanzaCollectorConfguration);
408            reflectedSelfPresence = selfPresenceCollector.nextResultOrThrow(conf.getTimeout());
409        }
410        catch (NotConnectedException | InterruptedException | NoResponseException | XMPPErrorException e) {
411            // Ensure that all callbacks are removed if there is an exception
412            removeConnectionCallbacks();
413            throw e;
414        }
415        finally {
416            if (presenceStanzaCollector != null) {
417                presenceStanzaCollector.cancel();
418            }
419        }
420
421        synchronized (presenceListener) {
422            // Only continue after we have received *and* processed the reflected self-presence. Since presences are
423            // handled in an extra listener, we may return from enter() without having processed all presences of the
424            // participants, resulting in a e.g. to low participant counter after enter(). Hence we wait here until the
425            // processing is done.
426            while (!processedReflectedSelfPresence) {
427                presenceListener.wait();
428            }
429        }
430
431        // This presence must be send from a full JID. We use the resourcepart of this JID as nick, since the room may
432        // performed roomnick rewriting
433        Resourcepart receivedNickname = reflectedSelfPresence.getFrom().getResourceOrThrow();
434        setNickname(receivedNickname);
435
436        // Update the list of joined rooms
437        multiUserChatManager.addJoinedRoom(room);
438        return reflectedSelfPresence;
439    }
440
441    private void setNickname(Resourcepart nickname) {
442        this.myRoomJid = JidCreate.entityFullFrom(room, nickname);
443    }
444
445    /**
446     * Get a new MUC enter configuration builder.
447     *
448     * @param nickname the nickname used when entering the MUC room.
449     * @return a new MUC enter configuration builder.
450     * @since 4.2
451     */
452    public MucEnterConfiguration.Builder getEnterConfigurationBuilder(Resourcepart nickname) {
453        return new MucEnterConfiguration.Builder(nickname, connection);
454    }
455
456    /**
457     * Creates the room according to some default configuration, assign the requesting user as the
458     * room owner, and add the owner to the room but not allow anyone else to enter the room
459     * (effectively "locking" the room). The requesting user will join the room under the specified
460     * nickname as soon as the room has been created.
461     * <p>
462     * To create an "Instant Room", that means a room with some default configuration that is
463     * available for immediate access, the room's owner should send an empty form after creating the
464     * room. Simply call {@link MucCreateConfigFormHandle#makeInstant()} on the returned {@link MucCreateConfigFormHandle}.
465     * </p>
466     * <p>
467     * To create a "Reserved Room", that means a room manually configured by the room creator before
468     * anyone is allowed to enter, the room's owner should complete and send a form after creating
469     * the room. Once the completed configuration form is sent to the server, the server will unlock
470     * the room. You can use the returned {@link MucCreateConfigFormHandle} to configure the room.
471     * </p>
472     *
473     * @param nickname the nickname to use.
474     * @return a handle to the MUC create configuration form API.
475     * @throws XMPPErrorException if the room couldn't be created for some reason (e.g. 405 error if
476     *         the user is not allowed to create the room)
477     * @throws NoResponseException if there was no response from the server.
478     * @throws InterruptedException if the calling thread was interrupted.
479     * @throws NotConnectedException if the XMPP connection is not connected.
480     * @throws MucAlreadyJoinedException if already joined the Multi-User Chat.7y
481     * @throws MissingMucCreationAcknowledgeException if there MUC creation was not acknowledged by the service.
482     * @throws NotAMucServiceException if the entity is not a MUC serivce.
483     */
484    public synchronized MucCreateConfigFormHandle create(Resourcepart nickname) throws NoResponseException,
485                    XMPPErrorException, InterruptedException, MucAlreadyJoinedException,
486                    NotConnectedException, MissingMucCreationAcknowledgeException, NotAMucServiceException {
487        if (isJoined()) {
488            throw new MucAlreadyJoinedException();
489        }
490
491        MucCreateConfigFormHandle mucCreateConfigFormHandle = createOrJoin(nickname);
492        if (mucCreateConfigFormHandle != null) {
493            // We successfully created a new room
494            return mucCreateConfigFormHandle;
495        }
496        // We need to leave the room since it seems that the room already existed
497        try {
498            leave();
499        }
500        catch (MucNotJoinedException e) {
501            LOGGER.log(Level.INFO, "Unexpected MucNotJoinedException", e);
502        }
503        throw new MissingMucCreationAcknowledgeException();
504    }
505
506    /**
507     * Create or join the MUC room with the given nickname.
508     *
509     * @param nickname the nickname to use in the MUC room.
510     * @return A {@link MucCreateConfigFormHandle} if the room was created while joining, or {@code null} if the room was just joined.
511     * @throws NoResponseException if there was no response from the remote entity.
512     * @throws XMPPErrorException if there was an XMPP error returned.
513     * @throws InterruptedException if the calling thread was interrupted.
514     * @throws NotConnectedException if the XMPP connection is not connected.
515     * @throws MucAlreadyJoinedException if already joined the Multi-User Chat.7y
516     * @throws NotAMucServiceException if the entity is not a MUC serivce.
517     */
518    public synchronized MucCreateConfigFormHandle createOrJoin(Resourcepart nickname) throws NoResponseException, XMPPErrorException,
519                    InterruptedException, MucAlreadyJoinedException, NotConnectedException, NotAMucServiceException {
520        MucEnterConfiguration mucEnterConfiguration = getEnterConfigurationBuilder(nickname).build();
521        return createOrJoin(mucEnterConfiguration);
522    }
523
524    /**
525     * Like {@link #create(Resourcepart)}, but will return a {@link MucCreateConfigFormHandle} if the room creation was acknowledged by
526     * the service (with an 201 status code). It's up to the caller to decide, based on the return
527     * value, if he needs to continue sending the room configuration. If {@code null} is returned, the room
528     * already existed and the user is able to join right away, without sending a form.
529     *
530     * @param mucEnterConfiguration the configuration used to enter the MUC.
531     * @return A {@link MucCreateConfigFormHandle} if the room was created while joining, or {@code null} if the room was just joined.
532     * @throws XMPPErrorException if the room couldn't be created for some reason (e.g. 405 error if
533     *         the user is not allowed to create the room)
534     * @throws NoResponseException if there was no response from the server.
535     * @throws InterruptedException if the calling thread was interrupted.
536     * @throws MucAlreadyJoinedException if the MUC is already joined
537     * @throws NotConnectedException if the XMPP connection is not connected.
538     * @throws NotAMucServiceException if the entity is not a MUC serivce.
539     */
540    public synchronized MucCreateConfigFormHandle createOrJoin(MucEnterConfiguration mucEnterConfiguration)
541                    throws NoResponseException, XMPPErrorException, InterruptedException, MucAlreadyJoinedException, NotConnectedException, NotAMucServiceException {
542        if (isJoined()) {
543            throw new MucAlreadyJoinedException();
544        }
545
546        Presence presence = enter(mucEnterConfiguration);
547
548        // Look for confirmation of room creation from the server
549        MUCUser mucUser = MUCUser.from(presence);
550        if (mucUser != null && mucUser.getStatus().contains(Status.ROOM_CREATED_201)) {
551            // Room was created and the user has joined the room
552            return new MucCreateConfigFormHandle();
553        }
554        return null;
555    }
556
557    /**
558     * A handle used to configure a newly created room. As long as the room is not configured it will be locked, which
559     * means that no one is able to join. The room will become unlocked as soon it got configured. In order to create an
560     * instant room, use {@link #makeInstant()}.
561     * <p>
562     * For advanced configuration options, use {@link MultiUserChat#getConfigurationForm()}, get the answer form with
563     * {@link Form#getFillableForm()}, fill it out and send it back to the room with
564     * {@link MultiUserChat#sendConfigurationForm(FillableForm)}.
565     * </p>
566     */
567    public class MucCreateConfigFormHandle {
568
569        /**
570         * Create an instant room. The default configuration will be accepted and the room will become unlocked, i.e.
571         * other users are able to join.
572         *
573         * @throws NoResponseException if there was no response from the remote entity.
574         * @throws XMPPErrorException if there was an XMPP error returned.
575         * @throws NotConnectedException if the XMPP connection is not connected.
576         * @throws InterruptedException if the calling thread was interrupted.
577         * @see <a href="http://www.xmpp.org/extensions/xep-0045.html#createroom-instant">XEP-45 § 10.1.2 Creating an
578         *      Instant Room</a>
579         */
580        public void makeInstant() throws NoResponseException, XMPPErrorException, NotConnectedException,
581                        InterruptedException {
582            sendConfigurationForm(null);
583        }
584
585        /**
586         * Alias for {@link MultiUserChat#getConfigFormManager()}.
587         *
588         * @return a MUC configuration form manager for this room.
589         * @throws NoResponseException if there was no response from the remote entity.
590         * @throws XMPPErrorException if there was an XMPP error returned.
591         * @throws NotConnectedException if the XMPP connection is not connected.
592         * @throws InterruptedException if the calling thread was interrupted.
593         * @see MultiUserChat#getConfigFormManager()
594         */
595        public MucConfigFormManager getConfigFormManager() throws NoResponseException,
596                        XMPPErrorException, NotConnectedException, InterruptedException {
597            return MultiUserChat.this.getConfigFormManager();
598        }
599    }
600
601    /**
602     * Create or join a MUC if it is necessary, i.e. if not the MUC is not already joined.
603     *
604     * @param nickname the required nickname to use.
605     * @param password the optional password required to join
606     * @return A {@link MucCreateConfigFormHandle} if the room was created while joining, or {@code null} if the room was just joined.
607     * @throws NoResponseException if there was no response from the remote entity.
608     * @throws XMPPErrorException if there was an XMPP error returned.
609     * @throws NotConnectedException if the XMPP connection is not connected.
610     * @throws InterruptedException if the calling thread was interrupted.
611     * @throws NotAMucServiceException if the entity is not a MUC serivce.
612     */
613    public MucCreateConfigFormHandle createOrJoinIfNecessary(Resourcepart nickname, String password) throws NoResponseException,
614                    XMPPErrorException, NotConnectedException, InterruptedException, NotAMucServiceException {
615        if (isJoined()) {
616            return null;
617        }
618        MucEnterConfiguration mucEnterConfiguration = getEnterConfigurationBuilder(nickname).withPassword(
619                        password).build();
620        try {
621            return createOrJoin(mucEnterConfiguration);
622        }
623        catch (MucAlreadyJoinedException e) {
624            return null;
625        }
626    }
627
628    /**
629     * Joins the chat room using the specified nickname. If already joined
630     * using another nickname, this method will first leave the room and then
631     * re-join using the new nickname. The default connection timeout for a reply
632     * from the group chat server that the join succeeded will be used. After
633     * joining the room, the room will decide the amount of history to send.
634     *
635     * @param nickname the nickname to use.
636     * @return the leave self-presence as reflected by the MUC.
637     * @throws NoResponseException if there was no response from the remote entity.
638     * @throws XMPPErrorException if an error occurs joining the room. In particular, a
639     *      401 error can occur if no password was provided and one is required; or a
640     *      403 error can occur if the user is banned; or a
641     *      404 error can occur if the room does not exist or is locked; or a
642     *      407 error can occur if user is not on the member list; or a
643     *      409 error can occur if someone is already in the group chat with the same nickname.
644     * @throws NoResponseException if there was no response from the server.
645     * @throws NotConnectedException if the XMPP connection is not connected.
646     * @throws InterruptedException if the calling thread was interrupted.
647     * @throws NotAMucServiceException if the entity is not a MUC serivce.
648     */
649    public Presence join(Resourcepart nickname) throws NoResponseException, XMPPErrorException,
650                    NotConnectedException, InterruptedException, NotAMucServiceException {
651        MucEnterConfiguration.Builder builder = getEnterConfigurationBuilder(nickname);
652        Presence reflectedJoinPresence = join(builder.build());
653        return reflectedJoinPresence;
654    }
655
656    /**
657     * Joins the chat room using the specified nickname and password. If already joined
658     * using another nickname, this method will first leave the room and then
659     * re-join using the new nickname. The default connection timeout for a reply
660     * from the group chat server that the join succeeded will be used. After
661     * joining the room, the room will decide the amount of history to send.<p>
662     *
663     * A password is required when joining password protected rooms. If the room does
664     * not require a password there is no need to provide one.
665     *
666     * @param nickname the nickname to use.
667     * @param password the password to use.
668     * @throws XMPPErrorException if an error occurs joining the room. In particular, a
669     *      401 error can occur if no password was provided and one is required; or a
670     *      403 error can occur if the user is banned; or a
671     *      404 error can occur if the room does not exist or is locked; or a
672     *      407 error can occur if user is not on the member list; or a
673     *      409 error can occur if someone is already in the group chat with the same nickname.
674     * @throws InterruptedException if the calling thread was interrupted.
675     * @throws NotConnectedException if the XMPP connection is not connected.
676     * @throws NoResponseException if there was no response from the server.
677     * @throws NotAMucServiceException if the entity is not a MUC serivce.
678     */
679    public void join(Resourcepart nickname, String password) throws XMPPErrorException, InterruptedException, NoResponseException, NotConnectedException, NotAMucServiceException {
680        MucEnterConfiguration.Builder builder = getEnterConfigurationBuilder(nickname).withPassword(
681                        password);
682        join(builder.build());
683    }
684
685    /**
686     * Joins the chat room using the specified nickname and password. If already joined
687     * using another nickname, this method will first leave the room and then
688     * re-join using the new nickname.<p>
689     *
690     * To control the amount of history to receive while joining a room you will need to provide
691     * a configured DiscussionHistory object.<p>
692     *
693     * A password is required when joining password protected rooms. If the room does
694     * not require a password there is no need to provide one.<p>
695     *
696     * If the room does not already exist when the user seeks to enter it, the server will
697     * decide to create a new room or not.
698     *
699     * @param mucEnterConfiguration the configuration used to enter the MUC.
700     * @return the join self-presence as reflected by the MUC.
701     * @throws XMPPErrorException if an error occurs joining the room. In particular, a
702     *      401 error can occur if no password was provided and one is required; or a
703     *      403 error can occur if the user is banned; or a
704     *      404 error can occur if the room does not exist or is locked; or a
705     *      407 error can occur if user is not on the member list; or a
706     *      409 error can occur if someone is already in the group chat with the same nickname.
707     * @throws NoResponseException if there was no response from the server.
708     * @throws NotConnectedException if the XMPP connection is not connected.
709     * @throws InterruptedException if the calling thread was interrupted.
710     * @throws NotAMucServiceException if the entity is not a MUC serivce.
711     */
712    public synchronized Presence join(MucEnterConfiguration mucEnterConfiguration)
713        throws XMPPErrorException, NoResponseException, NotConnectedException, InterruptedException, NotAMucServiceException {
714        // If we've already joined the room, leave it before joining under a new
715        // nickname.
716        if (isJoined()) {
717            try {
718                leaveSync();
719            }
720            catch (XMPPErrorException | NoResponseException | MucNotJoinedException e) {
721                LOGGER.log(Level.WARNING, "Could not leave MUC prior joining, assuming we are not joined", e);
722            }
723        }
724        Presence reflectedJoinPresence = enter(mucEnterConfiguration);
725        return reflectedJoinPresence;
726    }
727
728    /**
729     * Returns true if currently in the multi user chat (after calling the {@link
730     * #join(Resourcepart)} method).
731     *
732     * @return true if currently in the multi user chat room.
733     */
734    public boolean isJoined() {
735        return getMyRoomJid() != null;
736    }
737
738    /**
739     * Leave the chat room.
740     *
741     * @return the leave presence as reflected by the MUC.
742     * @throws NotConnectedException if the XMPP connection is not connected.
743     * @throws InterruptedException if the calling thread was interrupted.
744     * @throws XMPPErrorException if there was an XMPP error returned.
745     * @throws NoResponseException if there was no response from the remote entity.
746     * @throws MucNotJoinedException if not joined to the Multi-User Chat.
747     * @deprecated use {@link #leave()} instead.
748     */
749    @Deprecated
750    // TODO: Remove in Smack 4.5.
751    public synchronized Presence leaveSync() throws NotConnectedException, InterruptedException, MucNotJoinedException, NoResponseException, XMPPErrorException {
752        return leave();
753    }
754
755    /**
756     * Leave the chat room.
757     *
758     * @return the leave presence as reflected by the MUC.
759     * @throws NotConnectedException if the XMPP connection is not connected.
760     * @throws InterruptedException if the calling thread was interrupted.
761     * @throws XMPPErrorException if there was an XMPP error returned.
762     * @throws NoResponseException if there was no response from the remote entity.
763     * @throws MucNotJoinedException if not joined to the Multi-User Chat.
764     */
765    public synchronized Presence leave()
766                    throws NotConnectedException, InterruptedException, NoResponseException, XMPPErrorException, MucNotJoinedException {
767        //  Note that this method is intentionally not guarded by
768        // "if  (!joined) return" because it should be always be possible to leave the room in case the instance's
769        // state does not reflect the actual state.
770
771        final EntityFullJid myRoomJid = getMyRoomJid();
772        if (myRoomJid == null) {
773            throw new MucNotJoinedException(this);
774        }
775
776        // TODO: Consider adding a origin-id to the presence, once it is moved form smack-experimental into
777        // smack-extensions, in case the MUC service does not support stable IDs, and modify
778        // reflectedLeavePresenceFilters accordingly.
779
780        // We leave a room by sending a presence packet where the "to"
781        // field is in the form "roomName@service/nickname"
782        Presence leavePresence = connection.getStanzaFactory().buildPresenceStanza()
783                .ofType(Presence.Type.unavailable)
784                .to(myRoomJid)
785                .build();
786
787        List<StanzaFilter> reflectedLeavePresenceFilters = new ArrayList<>(3);
788        reflectedLeavePresenceFilters.add(StanzaTypeFilter.PRESENCE);
789        reflectedLeavePresenceFilters.add(new OrFilter(
790                        new AndFilter(FromMatchesFilter.createFull(myRoomJid), PresenceTypeFilter.UNAVAILABLE,
791                                        MUCUserStatusCodeFilter.STATUS_110_PRESENCE_TO_SELF),
792                        new AndFilter(fromRoomFilter, PresenceTypeFilter.ERROR)));
793
794        if (serviceSupportsStableIds()) {
795            reflectedLeavePresenceFilters.add(new StanzaIdFilter(leavePresence));
796        }
797
798        StanzaFilter reflectedLeavePresenceFilter = new AndFilter(reflectedLeavePresenceFilters);
799
800        Presence reflectedLeavePresence;
801        try {
802            reflectedLeavePresence = connection.createStanzaCollectorAndSend(reflectedLeavePresenceFilter, leavePresence).nextResultOrThrow();
803        } finally {
804            // Reset occupant information after we send the leave presence. This ensures that we only call userHasLeft()
805            // and reset the local MUC state after we successfully left the MUC (or if an exception occurred).
806            userHasLeft();
807        }
808
809        return reflectedLeavePresence;
810    }
811
812    /**
813     * Get a {@link MucConfigFormManager} to configure this room.
814     * <p>
815     * Only room owners are able to configure a room.
816     * </p>
817     *
818     * @return a MUC configuration form manager for this room.
819     * @throws NoResponseException if there was no response from the remote entity.
820     * @throws XMPPErrorException if there was an XMPP error returned.
821     * @throws NotConnectedException if the XMPP connection is not connected.
822     * @throws InterruptedException if the calling thread was interrupted.
823     * @see <a href="http://xmpp.org/extensions/xep-0045.html#roomconfig">XEP-45 § 10.2 Subsequent Room Configuration</a>
824     * @since 4.2
825     */
826    public MucConfigFormManager getConfigFormManager() throws NoResponseException,
827                    XMPPErrorException, NotConnectedException, InterruptedException {
828        return new MucConfigFormManager(this);
829    }
830
831    /**
832     * Returns the room's configuration form that the room's owner can use.
833     * The configuration form allows to set the room's language,
834     * enable logging, specify room's type, etc..
835     *
836     * @return the Form that contains the fields to complete together with the instrucions or
837     * <code>null</code> if no configuration is possible.
838     * @throws XMPPErrorException if an error occurs asking the configuration form for the room.
839     * @throws NoResponseException if there was no response from the server.
840     * @throws NotConnectedException if the XMPP connection is not connected.
841     * @throws InterruptedException if the calling thread was interrupted.
842     */
843    public Form getConfigurationForm() throws NoResponseException, XMPPErrorException, NotConnectedException, InterruptedException {
844        MUCOwner iq = new MUCOwner();
845        iq.setTo(room);
846        iq.setType(IQ.Type.get);
847
848        IQ answer = connection.sendIqRequestAndWaitForResponse(iq);
849        DataForm dataForm = DataForm.from(answer, MucConfigFormManager.FORM_TYPE);
850        return new Form(dataForm);
851    }
852
853    /**
854     * Sends the completed configuration form to the server. The room will be configured
855     * with the new settings defined in the form.
856     *
857     * @param form the form with the new settings.
858     * @throws XMPPErrorException if an error occurs setting the new rooms' configuration.
859     * @throws NoResponseException if there was no response from the server.
860     * @throws NotConnectedException if the XMPP connection is not connected.
861     * @throws InterruptedException if the calling thread was interrupted.
862     */
863    public void sendConfigurationForm(FillableForm form) throws NoResponseException, XMPPErrorException, NotConnectedException, InterruptedException {
864        final DataForm dataForm;
865        if (form != null) {
866            dataForm = form.getDataFormToSubmit();
867        } else {
868            // Instant room, cf. XEP-0045 § 10.1.2
869            dataForm = DataForm.builder().build();
870        }
871
872        MUCOwner iq = new MUCOwner();
873        iq.setTo(room);
874        iq.setType(IQ.Type.set);
875        iq.addExtension(dataForm);
876
877        connection.sendIqRequestAndWaitForResponse(iq);
878    }
879
880    /**
881     * Returns the room's registration form that an unaffiliated user, can use to become a member
882     * of the room or <code>null</code> if no registration is possible. Some rooms may restrict the
883     * privilege to register members and allow only room admins to add new members.<p>
884     *
885     * If the user requesting registration requirements is not allowed to register with the room
886     * (e.g. because that privilege has been restricted), the room will return a "Not Allowed"
887     * error to the user (error code 405).
888     *
889     * @return the registration Form that contains the fields to complete together with the
890     * instrucions or <code>null</code> if no registration is possible.
891     * @throws XMPPErrorException if an error occurs asking the registration form for the room or a
892     * 405 error if the user is not allowed to register with the room.
893     * @throws NoResponseException if there was no response from the server.
894     * @throws NotConnectedException if the XMPP connection is not connected.
895     * @throws InterruptedException if the calling thread was interrupted.
896     */
897    public Form getRegistrationForm() throws NoResponseException, XMPPErrorException, NotConnectedException, InterruptedException {
898        Registration reg = new Registration();
899        reg.setType(IQ.Type.get);
900        reg.setTo(room);
901
902        IQ result = connection.sendIqRequestAndWaitForResponse(reg);
903        DataForm dataForm = DataForm.from(result);
904        return new Form(dataForm);
905    }
906
907    /**
908     * Sends the completed registration form to the server. After the user successfully submits
909     * the form, the room may queue the request for review by the room admins or may immediately
910     * add the user to the member list by changing the user's affiliation from "none" to "member.<p>
911     *
912     * If the desired room nickname is already reserved for that room, the room will return a
913     * "Conflict" error to the user (error code 409). If the room does not support registration,
914     * it will return a "Service Unavailable" error to the user (error code 503).
915     *
916     * @param form the completed registration form.
917     * @throws XMPPErrorException if an error occurs submitting the registration form. In particular, a
918     *      409 error can occur if the desired room nickname is already reserved for that room;
919     *      or a 503 error can occur if the room does not support registration.
920     * @throws NoResponseException if there was no response from the server.
921     * @throws NotConnectedException if the XMPP connection is not connected.
922     * @throws InterruptedException if the calling thread was interrupted.
923     */
924    public void sendRegistrationForm(FillableForm form) throws NoResponseException, XMPPErrorException, NotConnectedException, InterruptedException {
925        Registration reg = new Registration();
926        reg.setType(IQ.Type.set);
927        reg.setTo(room);
928        reg.addExtension(form.getDataFormToSubmit());
929
930        connection.sendIqRequestAndWaitForResponse(reg);
931    }
932
933    /**
934     * Sends a request to destroy the room.
935     *
936     * @throws XMPPErrorException if an error occurs while trying to destroy the room.
937     *      An error can occur which will be wrapped by an XMPPException --
938     *      XMPP error code 403. The error code can be used to present more
939     *      appropriate error messages to end-users.
940     * @throws NoResponseException if there was no response from the server.
941     * @throws NotConnectedException if the XMPP connection is not connected.
942     * @throws InterruptedException if the calling thread was interrupted.
943     * @see #destroy(String, EntityBareJid)
944     * @since 4.5
945     */
946    public void destroy() throws NoResponseException, XMPPErrorException, NotConnectedException, InterruptedException {
947        destroy(null, null);
948    }
949
950    /**
951     * Sends a request to the server to destroy the room. The sender of the request
952     * should be the room's owner. If the sender of the destroy request is not the room's owner
953     * then the server will answer a "Forbidden" error (403).
954     *
955     * @param reason an optional reason for the room destruction.
956     * @param alternateJID an optional JID of an alternate location.
957     * @throws XMPPErrorException if an error occurs while trying to destroy the room.
958     *      An error can occur which will be wrapped by an XMPPException --
959     *      XMPP error code 403. The error code can be used to present more
960     *      appropriate error messages to end-users.
961     * @throws NoResponseException if there was no response from the server.
962     * @throws NotConnectedException if the XMPP connection is not connected.
963     * @throws InterruptedException if the calling thread was interrupted.
964     */
965    public void destroy(String reason, EntityBareJid alternateJID) throws NoResponseException, XMPPErrorException, NotConnectedException, InterruptedException {
966        MUCOwner iq = new MUCOwner();
967        iq.setTo(room);
968        iq.setType(IQ.Type.set);
969
970        // Create the reason for the room destruction
971        Destroy destroy = new Destroy(alternateJID, reason);
972        iq.setDestroy(destroy);
973
974        try {
975            connection.sendIqRequestAndWaitForResponse(iq);
976        }
977        catch (XMPPErrorException e) {
978            // Note that we do not call userHasLeft() here because an XMPPErrorException would usually indicate that the
979            // room was not destroyed and we therefore we also did not leave the room.
980            throw e;
981        }
982        catch (NoResponseException | NotConnectedException | InterruptedException e) {
983            // Reset occupant information.
984            userHasLeft();
985            throw e;
986        }
987
988        // Reset occupant information.
989        userHasLeft();
990    }
991
992    /**
993     * Invites another user to the room in which one is an occupant. The invitation
994     * will be sent to the room which in turn will forward the invitation to the invitee.<p>
995     *
996     * If the room is password-protected, the invitee will receive a password to use to join
997     * the room. If the room is members-only, the the invitee may be added to the member list.
998     *
999     * @param user the user to invite to the room.(e.g. hecate@shakespeare.lit)
1000     * @param reason the reason why the user is being invited.
1001     * @throws NotConnectedException if the XMPP connection is not connected.
1002     * @throws InterruptedException if the calling thread was interrupted.
1003     */
1004    public void invite(EntityBareJid user, String reason) throws NotConnectedException, InterruptedException {
1005        invite(connection.getStanzaFactory().buildMessageStanza(), user, reason);
1006    }
1007
1008    /**
1009     * Invites another user to the room in which one is an occupant using a given Message. The invitation
1010     * will be sent to the room which in turn will forward the invitation to the invitee.<p>
1011     *
1012     * If the room is password-protected, the invitee will receive a password to use to join
1013     * the room. If the room is members-only, the the invitee may be added to the member list.
1014     *
1015     * @param message the message to use for sending the invitation.
1016     * @param user the user to invite to the room.(e.g. hecate@shakespeare.lit)
1017     * @param reason the reason why the user is being invited.
1018     * @throws NotConnectedException if the XMPP connection is not connected.
1019     * @throws InterruptedException if the calling thread was interrupted.
1020     * @deprecated use {@link #invite(MessageBuilder, EntityBareJid, String)} instead.
1021     */
1022    @Deprecated
1023    // TODO: Remove in Smack 4.5.
1024    public void invite(Message message, EntityBareJid user, String reason) throws NotConnectedException, InterruptedException {
1025        // TODO listen for 404 error code when inviter supplies a non-existent JID
1026        message.setTo(room);
1027
1028        // Create the MUCUser packet that will include the invitation
1029        MUCUser mucUser = new MUCUser();
1030        MUCUser.Invite invite = new MUCUser.Invite(reason, user);
1031        mucUser.setInvite(invite);
1032        // Add the MUCUser packet that includes the invitation to the message
1033        message.addExtension(mucUser);
1034
1035        connection.sendStanza(message);
1036    }
1037
1038    /**
1039     * Invites another user to the room in which one is an occupant using a given Message. The invitation
1040     * will be sent to the room which in turn will forward the invitation to the invitee.<p>
1041     *
1042     * If the room is password-protected, the invitee will receive a password to use to join
1043     * the room. If the room is members-only, the the invitee may be added to the member list.
1044     *
1045     * @param messageBuilder the message to use for sending the invitation.
1046     * @param user the user to invite to the room.(e.g. hecate@shakespeare.lit)
1047     * @param reason the reason why the user is being invited.
1048     * @throws NotConnectedException if the XMPP connection is not connected.
1049     * @throws InterruptedException if the calling thread was interrupted.
1050     */
1051    public void invite(MessageBuilder messageBuilder, EntityBareJid user, String reason) throws NotConnectedException, InterruptedException {
1052        // TODO listen for 404 error code when inviter supplies a non-existent JID
1053        messageBuilder.to(room);
1054
1055        // Create the MUCUser packet that will include the invitation
1056        MUCUser mucUser = new MUCUser();
1057        MUCUser.Invite invite = new MUCUser.Invite(reason, user);
1058        mucUser.setInvite(invite);
1059        // Add the MUCUser packet that includes the invitation to the message
1060        messageBuilder.addExtension(mucUser);
1061
1062        Message message = messageBuilder.build();
1063        connection.sendStanza(message);
1064    }
1065
1066    /**
1067     * Adds a listener to invitation rejections notifications. The listener will be fired anytime
1068     * an invitation is declined.
1069     *
1070     * @param listener an invitation rejection listener.
1071     * @return true if the listener was not already added.
1072     */
1073    public boolean addInvitationRejectionListener(InvitationRejectionListener listener) {
1074         return invitationRejectionListeners.add(listener);
1075    }
1076
1077    /**
1078     * Removes a listener from invitation rejections notifications. The listener will be fired
1079     * anytime an invitation is declined.
1080     *
1081     * @param listener an invitation rejection listener.
1082     * @return true if the listener was registered and is now removed.
1083     */
1084    public boolean removeInvitationRejectionListener(InvitationRejectionListener listener) {
1085        return invitationRejectionListeners.remove(listener);
1086    }
1087
1088    /**
1089     * Fires invitation rejection listeners.
1090     *
1091     * @param message the message.
1092     * @param rejection the information about the rejection.
1093     */
1094    private void fireInvitationRejectionListeners(Message message, MUCUser.Decline rejection) {
1095        EntityBareJid invitee = rejection.getFrom();
1096        String reason = rejection.getReason();
1097        InvitationRejectionListener[] listeners;
1098        synchronized (invitationRejectionListeners) {
1099            listeners = new InvitationRejectionListener[invitationRejectionListeners.size()];
1100            invitationRejectionListeners.toArray(listeners);
1101        }
1102        for (InvitationRejectionListener listener : listeners) {
1103            listener.invitationDeclined(invitee, reason, message, rejection);
1104        }
1105    }
1106
1107    /**
1108     * Adds a listener to subject change notifications. The listener will be fired anytime
1109     * the room's subject changes.
1110     *
1111     * @param listener a subject updated listener.
1112     * @return true if the listener was not already added.
1113     */
1114    public boolean addSubjectUpdatedListener(SubjectUpdatedListener listener) {
1115        return subjectUpdatedListeners.add(listener);
1116    }
1117
1118    /**
1119     * Removes a listener from subject change notifications. The listener will be fired
1120     * anytime the room's subject changes.
1121     *
1122     * @param listener a subject updated listener.
1123     * @return true if the listener was registered and is now removed.
1124     */
1125    public boolean removeSubjectUpdatedListener(SubjectUpdatedListener listener) {
1126        return subjectUpdatedListeners.remove(listener);
1127    }
1128
1129    /**
1130     * Adds a new {@link StanzaListener} that will be invoked every time a new presence
1131     * is going to be sent by this MultiUserChat to the server. Stanza interceptors may
1132     * add new extensions to the presence that is going to be sent to the MUC service.
1133     *
1134     * @param presenceInterceptor the new stanza interceptor that will intercept presence packets.
1135     */
1136    public void addPresenceInterceptor(Consumer<PresenceBuilder> presenceInterceptor) {
1137        boolean added = presenceInterceptors.add(presenceInterceptor);
1138        if (!added) return;
1139        int currentCount = presenceInterceptorCount.incrementAndGet();
1140        if (currentCount == 1) {
1141            connection.addPresenceInterceptor(this.presenceInterceptor, ToMatchesFilter.create(room).asPredicate(Presence.class));
1142        }
1143    }
1144
1145    /**
1146     * Removes a {@link StanzaListener} that was being invoked every time a new presence
1147     * was being sent by this MultiUserChat to the server. Stanza interceptors may
1148     * add new extensions to the presence that is going to be sent to the MUC service.
1149     *
1150     * @param presenceInterceptor the stanza interceptor to remove.
1151     */
1152    public void removePresenceInterceptor(Consumer<PresenceBuilder> presenceInterceptor) {
1153        boolean removed = presenceInterceptors.remove(presenceInterceptor);
1154        if (!removed) return;
1155        int currentCount = presenceInterceptorCount.decrementAndGet();
1156        if (currentCount == 0) {
1157            connection.removePresenceInterceptor(presenceInterceptor);
1158        }
1159    }
1160
1161    /**
1162     * Returns the last known room's subject or <code>null</code> if the user hasn't joined the room
1163     * or the room does not have a subject yet. In case the room has a subject, as soon as the
1164     * user joins the room a message with the current room's subject will be received.<p>
1165     *
1166     * To be notified every time the room's subject change you should add a listener
1167     * to this room. {@link #addSubjectUpdatedListener(SubjectUpdatedListener)}<p>
1168     *
1169     * To change the room's subject use {@link #changeSubject(String)}.
1170     *
1171     * @return the room's subject or <code>null</code> if the user hasn't joined the room or the
1172     * room does not have a subject yet.
1173     */
1174    public String getSubject() {
1175        return subject;
1176    }
1177
1178    /**
1179     * Returns the reserved room nickname for the user in the room. A user may have a reserved
1180     * nickname, for example through explicit room registration or database integration. In such
1181     * cases it may be desirable for the user to discover the reserved nickname before attempting
1182     * to enter the room.
1183     *
1184     * @return the reserved room nickname or <code>null</code> if none.
1185     * @throws SmackException if there was no response from the server.
1186     * @throws InterruptedException if the calling thread was interrupted.
1187     */
1188    public String getReservedNickname() throws SmackException, InterruptedException {
1189        try {
1190            DiscoverInfo result =
1191                ServiceDiscoveryManager.getInstanceFor(connection).discoverInfo(
1192                    room,
1193                    "x-roomuser-item");
1194            // Look for an Identity that holds the reserved nickname and return its name
1195            for (DiscoverInfo.Identity identity : result.getIdentities()) {
1196                return identity.getName();
1197            }
1198        }
1199        catch (XMPPException e) {
1200            LOGGER.log(Level.SEVERE, "Error retrieving room nickname", e);
1201        }
1202        // If no Identity was found then the user does not have a reserved room nickname
1203        return null;
1204    }
1205
1206    /**
1207     * Returns the nickname that was used to join the room, or <code>null</code> if not
1208     * currently joined.
1209     *
1210     * @return the nickname currently being used.
1211     */
1212    public Resourcepart getNickname() {
1213        final EntityFullJid myRoomJid = getMyRoomJid();
1214        if (myRoomJid == null) {
1215            return null;
1216        }
1217        return myRoomJid.getResourcepart();
1218    }
1219
1220    /**
1221     * Return the full JID of the user in the room, or <code>null</code> if the room is not joined.
1222     *
1223     * @return the full JID of the user in the room, or <code>null</code>.
1224     * @since 4.5.0
1225     */
1226    public EntityFullJid getMyRoomJid() {
1227        return myRoomJid;
1228    }
1229
1230    /**
1231     * Changes the occupant's nickname to a new nickname within the room. Each room occupant
1232     * will receive two presence packets. One of type "unavailable" for the old nickname and one
1233     * indicating availability for the new nickname. The unavailable presence will contain the new
1234     * nickname and an appropriate status code (namely 303) as extended presence information. The
1235     * status code 303 indicates that the occupant is changing his/her nickname.
1236     *
1237     * @param nickname the new nickname within the room.
1238     * @throws XMPPErrorException if the new nickname is already in use by another occupant.
1239     * @throws NoResponseException if there was no response from the server.
1240     * @throws NotConnectedException if the XMPP connection is not connected.
1241     * @throws InterruptedException if the calling thread was interrupted.
1242     * @throws MucNotJoinedException if not joined to the Multi-User Chat.
1243     */
1244    public synchronized void changeNickname(Resourcepart nickname) throws NoResponseException, XMPPErrorException, NotConnectedException, InterruptedException, MucNotJoinedException  {
1245        Objects.requireNonNull(nickname, "Nickname must not be null or blank.");
1246        // Check that we already have joined the room before attempting to change the
1247        // nickname.
1248        if (!isJoined()) {
1249            throw new MucNotJoinedException(this);
1250        }
1251        final EntityFullJid jid = JidCreate.entityFullFrom(room, nickname);
1252        // We change the nickname by sending a presence packet where the "to"
1253        // field is in the form "roomName@service/nickname"
1254        // We don't have to signal the MUC support again
1255        Presence joinPresence = connection.getStanzaFactory().buildPresenceStanza()
1256                .to(jid)
1257                .ofType(Presence.Type.available)
1258                .build();
1259
1260        // Wait for a presence packet back from the server.
1261        StanzaFilter responseFilter =
1262            new AndFilter(
1263                FromMatchesFilter.createFull(jid),
1264                new StanzaTypeFilter(Presence.class));
1265        StanzaCollector response = connection.createStanzaCollectorAndSend(responseFilter, joinPresence);
1266        // Wait up to a certain number of seconds for a reply. If there is a negative reply, an
1267        // exception will be thrown
1268        response.nextResultOrThrow();
1269
1270        // TODO: Shouldn't this handle nickname rewriting by the MUC service?
1271        setNickname(nickname);
1272    }
1273
1274    /**
1275     * Changes the occupant's availability status within the room. The presence type
1276     * will remain available but with a new status that describes the presence update and
1277     * a new presence mode (e.g. Extended away).
1278     *
1279     * @param status a text message describing the presence update.
1280     * @param mode the mode type for the presence update.
1281     * @throws NotConnectedException if the XMPP connection is not connected.
1282     * @throws InterruptedException if the calling thread was interrupted.
1283     * @throws MucNotJoinedException if not joined to the Multi-User Chat.
1284     */
1285    public void changeAvailabilityStatus(String status, Presence.Mode mode) throws NotConnectedException, InterruptedException, MucNotJoinedException {
1286        final EntityFullJid myRoomJid = getMyRoomJid();
1287        if (myRoomJid == null) {
1288            throw new MucNotJoinedException(this);
1289        }
1290
1291        // We change the availability status by sending a presence packet to the room with the
1292        // new presence status and mode
1293        Presence joinPresence = connection.getStanzaFactory().buildPresenceStanza()
1294                .to(myRoomJid)
1295                .ofType(Presence.Type.available)
1296                .setStatus(status)
1297                .setMode(mode)
1298                .build();
1299
1300        // Send join packet.
1301        connection.sendStanza(joinPresence);
1302    }
1303
1304    /**
1305     * Kicks a visitor or participant from the room. The kicked occupant will receive a presence
1306     * of type "unavailable" including a status code 307 and optionally along with the reason
1307     * (if provided) and the bare JID of the user who initiated the kick. After the occupant
1308     * was kicked from the room, the rest of the occupants will receive a presence of type
1309     * "unavailable". The presence will include a status code 307 which means that the occupant
1310     * was kicked from the room.
1311     *
1312     * @param nickname the nickname of the participant or visitor to kick from the room
1313     * (e.g. "john").
1314     * @param reason the reason why the participant or visitor is being kicked from the room.
1315     * @throws XMPPErrorException if an error occurs kicking the occupant. In particular, a
1316     *      405 error can occur if a moderator or a user with an affiliation of "owner" or "admin"
1317     *      was intended to be kicked (i.e. Not Allowed error); or a
1318     *      403 error can occur if the occupant that intended to kick another occupant does
1319     *      not have kicking privileges (i.e. Forbidden error); or a
1320     *      400 error can occur if the provided nickname is not present in the room.
1321     * @throws NoResponseException if there was no response from the server.
1322     * @throws NotConnectedException if the XMPP connection is not connected.
1323     * @throws InterruptedException if the calling thread was interrupted.
1324     */
1325    public void kickParticipant(Resourcepart nickname, String reason) throws XMPPErrorException, NoResponseException, NotConnectedException, InterruptedException {
1326        changeRole(nickname, MUCRole.none, reason);
1327    }
1328
1329    /**
1330     * Sends a voice request to the MUC. The room moderators usually need to approve this request.
1331     *
1332     * @throws NotConnectedException if the XMPP connection is not connected.
1333     * @throws InterruptedException if the calling thread was interrupted.
1334     * @see <a href="http://xmpp.org/extensions/xep-0045.html#requestvoice">XEP-45 § 7.13 Requesting
1335     *      Voice</a>
1336     * @since 4.1
1337     */
1338    public void requestVoice() throws NotConnectedException, InterruptedException {
1339        DataForm.Builder form = DataForm.builder()
1340                        .setFormType(MUCInitialPresence.NAMESPACE + "#request");
1341
1342        TextSingleFormField.Builder requestVoiceField = FormField.textSingleBuilder("muc#role");
1343        requestVoiceField.setLabel("Requested role");
1344        requestVoiceField.setValue("participant");
1345        form.addField(requestVoiceField.build());
1346
1347        Message message = connection.getStanzaFactory().buildMessageStanza()
1348                .to(room)
1349                .addExtension(form.build())
1350                .build();
1351        connection.sendStanza(message);
1352    }
1353
1354    /**
1355     * Grants voice to visitors in the room. In a moderated room, a moderator may want to manage
1356     * who does and does not have "voice" in the room. To have voice means that a room occupant
1357     * is able to send messages to the room occupants.
1358     *
1359     * @param nicknames the nicknames of the visitors to grant voice in the room (e.g. "john").
1360     * @throws XMPPErrorException if an error occurs granting voice to a visitor. In particular, a
1361     *      403 error can occur if the occupant that intended to grant voice is not
1362     *      a moderator in this room (i.e. Forbidden error); or a
1363     *      400 error can occur if the provided nickname is not present in the room.
1364     * @throws NoResponseException if there was no response from the server.
1365     * @throws NotConnectedException if the XMPP connection is not connected.
1366     * @throws InterruptedException if the calling thread was interrupted.
1367     */
1368    public void grantVoice(Collection<Resourcepart> nicknames) throws XMPPErrorException, NoResponseException, NotConnectedException, InterruptedException {
1369        changeRole(nicknames, MUCRole.participant);
1370    }
1371
1372    /**
1373     * Grants voice to a visitor in the room. In a moderated room, a moderator may want to manage
1374     * who does and does not have "voice" in the room. To have voice means that a room occupant
1375     * is able to send messages to the room occupants.
1376     *
1377     * @param nickname the nickname of the visitor to grant voice in the room (e.g. "john").
1378     * @throws XMPPErrorException if an error occurs granting voice to a visitor. In particular, a
1379     *      403 error can occur if the occupant that intended to grant voice is not
1380     *      a moderator in this room (i.e. Forbidden error); or a
1381     *      400 error can occur if the provided nickname is not present in the room.
1382     * @throws NoResponseException if there was no response from the server.
1383     * @throws NotConnectedException if the XMPP connection is not connected.
1384     * @throws InterruptedException if the calling thread was interrupted.
1385     */
1386    public void grantVoice(Resourcepart nickname) throws XMPPErrorException, NoResponseException, NotConnectedException, InterruptedException {
1387        changeRole(nickname, MUCRole.participant, null);
1388    }
1389
1390    /**
1391     * Revokes voice from participants in the room. In a moderated room, a moderator may want to
1392     * revoke an occupant's privileges to speak. To have voice means that a room occupant
1393     * is able to send messages to the room occupants.
1394     *
1395     * @param nicknames the nicknames of the participants to revoke voice (e.g. "john").
1396     * @throws XMPPErrorException if an error occurs revoking voice from a participant. In particular, a
1397     *      405 error can occur if a moderator or a user with an affiliation of "owner" or "admin"
1398     *      was tried to revoke his voice (i.e. Not Allowed error); or a
1399     *      400 error can occur if the provided nickname is not present in the room.
1400     * @throws NoResponseException if there was no response from the server.
1401     * @throws NotConnectedException if the XMPP connection is not connected.
1402     * @throws InterruptedException if the calling thread was interrupted.
1403     */
1404    public void revokeVoice(Collection<Resourcepart> nicknames) throws XMPPErrorException, NoResponseException, NotConnectedException, InterruptedException {
1405        changeRole(nicknames, MUCRole.visitor);
1406    }
1407
1408    /**
1409     * Revokes voice from a participant in the room. In a moderated room, a moderator may want to
1410     * revoke an occupant's privileges to speak. To have voice means that a room occupant
1411     * is able to send messages to the room occupants.
1412     *
1413     * @param nickname the nickname of the participant to revoke voice (e.g. "john").
1414     * @throws XMPPErrorException if an error occurs revoking voice from a participant. In particular, a
1415     *      405 error can occur if a moderator or a user with an affiliation of "owner" or "admin"
1416     *      was tried to revoke his voice (i.e. Not Allowed error); or a
1417     *      400 error can occur if the provided nickname is not present in the room.
1418     * @throws NoResponseException if there was no response from the server.
1419     * @throws NotConnectedException if the XMPP connection is not connected.
1420     * @throws InterruptedException if the calling thread was interrupted.
1421     */
1422    public void revokeVoice(Resourcepart nickname) throws XMPPErrorException, NoResponseException, NotConnectedException, InterruptedException {
1423        changeRole(nickname, MUCRole.visitor, null);
1424    }
1425
1426    /**
1427     * Bans users from the room. An admin or owner of the room can ban users from a room. This
1428     * means that the banned user will no longer be able to join the room unless the ban has been
1429     * removed. If the banned user was present in the room then he/she will be removed from the
1430     * room and notified that he/she was banned along with the reason (if provided) and the bare
1431     * XMPP user ID of the user who initiated the ban.
1432     *
1433     * @param jids the bare XMPP user IDs of the users to ban.
1434     * @throws XMPPErrorException if an error occurs banning a user. In particular, a
1435     *      405 error can occur if a moderator or a user with an affiliation of "owner" or "admin"
1436     *      was tried to be banned (i.e. Not Allowed error).
1437     * @throws NoResponseException if there was no response from the server.
1438     * @throws NotConnectedException if the XMPP connection is not connected.
1439     * @throws InterruptedException if the calling thread was interrupted.
1440     */
1441    public void banUsers(Collection<? extends Jid> jids) throws XMPPErrorException, NoResponseException, NotConnectedException, InterruptedException {
1442        changeAffiliationByAdmin(jids, MUCAffiliation.outcast);
1443    }
1444
1445    /**
1446     * Bans a user from the room. An admin or owner of the room can ban users from a room. This
1447     * means that the banned user will no longer be able to join the room unless the ban has been
1448     * removed. If the banned user was present in the room then he/she will be removed from the
1449     * room and notified that he/she was banned along with the reason (if provided) and the bare
1450     * XMPP user ID of the user who initiated the ban.
1451     *
1452     * @param jid the bare XMPP user ID of the user to ban (e.g. "user@host.org").
1453     * @param reason the optional reason why the user was banned.
1454     * @throws XMPPErrorException if an error occurs banning a user. In particular, a
1455     *      405 error can occur if a moderator or a user with an affiliation of "owner" or "admin"
1456     *      was tried to be banned (i.e. Not Allowed error).
1457     * @throws NoResponseException if there was no response from the server.
1458     * @throws NotConnectedException if the XMPP connection is not connected.
1459     * @throws InterruptedException if the calling thread was interrupted.
1460     */
1461    public void banUser(Jid jid, String reason) throws XMPPErrorException, NoResponseException, NotConnectedException, InterruptedException {
1462        changeAffiliationByAdmin(jid, MUCAffiliation.outcast, reason);
1463    }
1464
1465    /**
1466     * Grants membership to other users. Only administrators are able to grant membership. A user
1467     * that becomes a room member will be able to enter a room of type Members-Only (i.e. a room
1468     * that a user cannot enter without being on the member list).
1469     *
1470     * @param jids the XMPP user IDs of the users to grant membership.
1471     * @throws XMPPErrorException if an error occurs granting membership to a user.
1472     * @throws NoResponseException if there was no response from the server.
1473     * @throws NotConnectedException if the XMPP connection is not connected.
1474     * @throws InterruptedException if the calling thread was interrupted.
1475     */
1476    public void grantMembership(Collection<? extends Jid> jids) throws XMPPErrorException, NoResponseException, NotConnectedException, InterruptedException {
1477        changeAffiliationByAdmin(jids, MUCAffiliation.member);
1478    }
1479
1480    /**
1481     * Grants membership to a user. Only administrators are able to grant membership. A user
1482     * that becomes a room member will be able to enter a room of type Members-Only (i.e. a room
1483     * that a user cannot enter without being on the member list).
1484     *
1485     * @param jid the XMPP user ID of the user to grant membership (e.g. "user@host.org").
1486     * @throws XMPPErrorException if an error occurs granting membership to a user.
1487     * @throws NoResponseException if there was no response from the server.
1488     * @throws NotConnectedException if the XMPP connection is not connected.
1489     * @throws InterruptedException if the calling thread was interrupted.
1490     */
1491    public void grantMembership(Jid jid) throws XMPPErrorException, NoResponseException, NotConnectedException, InterruptedException {
1492        changeAffiliationByAdmin(jid, MUCAffiliation.member, null);
1493    }
1494
1495    /**
1496     * Revokes users' membership. Only administrators are able to revoke membership. A user
1497     * that becomes a room member will be able to enter a room of type Members-Only (i.e. a room
1498     * that a user cannot enter without being on the member list). If the user is in the room and
1499     * the room is of type members-only then the user will be removed from the room.
1500     *
1501     * @param jids the bare XMPP user IDs of the users to revoke membership.
1502     * @throws XMPPErrorException if an error occurs revoking membership to a user.
1503     * @throws NoResponseException if there was no response from the server.
1504     * @throws NotConnectedException if the XMPP connection is not connected.
1505     * @throws InterruptedException if the calling thread was interrupted.
1506     */
1507    public void revokeMembership(Collection<? extends Jid> jids) throws XMPPErrorException, NoResponseException, NotConnectedException, InterruptedException {
1508        changeAffiliationByAdmin(jids, MUCAffiliation.none);
1509    }
1510
1511    /**
1512     * Revokes a user's membership. Only administrators are able to revoke membership. A user
1513     * that becomes a room member will be able to enter a room of type Members-Only (i.e. a room
1514     * that a user cannot enter without being on the member list). If the user is in the room and
1515     * the room is of type members-only then the user will be removed from the room.
1516     *
1517     * @param jid the bare XMPP user ID of the user to revoke membership (e.g. "user@host.org").
1518     * @throws XMPPErrorException if an error occurs revoking membership to a user.
1519     * @throws NoResponseException if there was no response from the server.
1520     * @throws NotConnectedException if the XMPP connection is not connected.
1521     * @throws InterruptedException if the calling thread was interrupted.
1522     */
1523    public void revokeMembership(Jid jid) throws XMPPErrorException, NoResponseException, NotConnectedException, InterruptedException {
1524        changeAffiliationByAdmin(jid, MUCAffiliation.none, null);
1525    }
1526
1527    /**
1528     * Grants moderator privileges to participants or visitors. Room administrators may grant
1529     * moderator privileges. A moderator is allowed to kick users, grant and revoke voice, invite
1530     * other users, modify room's subject plus all the partcipants privileges.
1531     *
1532     * @param nicknames the nicknames of the occupants to grant moderator privileges.
1533     * @throws XMPPErrorException if an error occurs granting moderator privileges to a user.
1534     * @throws NoResponseException if there was no response from the server.
1535     * @throws NotConnectedException if the XMPP connection is not connected.
1536     * @throws InterruptedException if the calling thread was interrupted.
1537     */
1538    public void grantModerator(Collection<Resourcepart> nicknames) throws XMPPErrorException, NoResponseException, NotConnectedException, InterruptedException {
1539        changeRole(nicknames, MUCRole.moderator);
1540    }
1541
1542    /**
1543     * Grants moderator privileges to a participant or visitor. Room administrators may grant
1544     * moderator privileges. A moderator is allowed to kick users, grant and revoke voice, invite
1545     * other users, modify room's subject plus all the partcipants privileges.
1546     *
1547     * @param nickname the nickname of the occupant to grant moderator privileges.
1548     * @throws XMPPErrorException if an error occurs granting moderator privileges to a user.
1549     * @throws NoResponseException if there was no response from the server.
1550     * @throws NotConnectedException if the XMPP connection is not connected.
1551     * @throws InterruptedException if the calling thread was interrupted.
1552     */
1553    public void grantModerator(Resourcepart nickname) throws XMPPErrorException, NoResponseException, NotConnectedException, InterruptedException {
1554        changeRole(nickname, MUCRole.moderator, null);
1555    }
1556
1557    /**
1558     * Revokes moderator privileges from other users. The occupant that loses moderator
1559     * privileges will become a participant. Room administrators may revoke moderator privileges
1560     * only to occupants whose affiliation is member or none. This means that an administrator is
1561     * not allowed to revoke moderator privileges from other room administrators or owners.
1562     *
1563     * @param nicknames the nicknames of the occupants to revoke moderator privileges.
1564     * @throws XMPPErrorException if an error occurs revoking moderator privileges from a user.
1565     * @throws NoResponseException if there was no response from the server.
1566     * @throws NotConnectedException if the XMPP connection is not connected.
1567     * @throws InterruptedException if the calling thread was interrupted.
1568     */
1569    public void revokeModerator(Collection<Resourcepart> nicknames) throws XMPPErrorException, NoResponseException, NotConnectedException, InterruptedException {
1570        changeRole(nicknames, MUCRole.participant);
1571    }
1572
1573    /**
1574     * Revokes moderator privileges from another user. The occupant that loses moderator
1575     * privileges will become a participant. Room administrators may revoke moderator privileges
1576     * only to occupants whose affiliation is member or none. This means that an administrator is
1577     * not allowed to revoke moderator privileges from other room administrators or owners.
1578     *
1579     * @param nickname the nickname of the occupant to revoke moderator privileges.
1580     * @throws XMPPErrorException if an error occurs revoking moderator privileges from a user.
1581     * @throws NoResponseException if there was no response from the server.
1582     * @throws NotConnectedException if the XMPP connection is not connected.
1583     * @throws InterruptedException if the calling thread was interrupted.
1584     */
1585    public void revokeModerator(Resourcepart nickname) throws XMPPErrorException, NoResponseException, NotConnectedException, InterruptedException {
1586        changeRole(nickname, MUCRole.participant, null);
1587    }
1588
1589    /**
1590     * Grants ownership privileges to other users. Room owners may grant ownership privileges.
1591     * Some room implementations will not allow to grant ownership privileges to other users.
1592     * An owner is allowed to change defining room features as well as perform all administrative
1593     * functions.
1594     *
1595     * @param jids the collection of bare XMPP user IDs of the users to grant ownership.
1596     * @throws XMPPErrorException if an error occurs granting ownership privileges to a user.
1597     * @throws NoResponseException if there was no response from the server.
1598     * @throws NotConnectedException if the XMPP connection is not connected.
1599     * @throws InterruptedException if the calling thread was interrupted.
1600     */
1601    public void grantOwnership(Collection<? extends Jid> jids) throws XMPPErrorException, NoResponseException, NotConnectedException, InterruptedException {
1602        changeAffiliationByAdmin(jids, MUCAffiliation.owner);
1603    }
1604
1605    /**
1606     * Grants ownership privileges to another user. Room owners may grant ownership privileges.
1607     * Some room implementations will not allow to grant ownership privileges to other users.
1608     * An owner is allowed to change defining room features as well as perform all administrative
1609     * functions.
1610     *
1611     * @param jid the bare XMPP user ID of the user to grant ownership (e.g. "user@host.org").
1612     * @throws XMPPErrorException if an error occurs granting ownership privileges to a user.
1613     * @throws NoResponseException if there was no response from the server.
1614     * @throws NotConnectedException if the XMPP connection is not connected.
1615     * @throws InterruptedException if the calling thread was interrupted.
1616     */
1617    public void grantOwnership(Jid jid) throws XMPPErrorException, NoResponseException, NotConnectedException, InterruptedException {
1618        changeAffiliationByAdmin(jid, MUCAffiliation.owner, null);
1619    }
1620
1621    /**
1622     * Revokes ownership privileges from other users. The occupant that loses ownership
1623     * privileges will become an administrator. Room owners may revoke ownership privileges.
1624     * Some room implementations will not allow to grant ownership privileges to other users.
1625     *
1626     * @param jids the bare XMPP user IDs of the users to revoke ownership.
1627     * @throws XMPPErrorException if an error occurs revoking ownership privileges from a user.
1628     * @throws NoResponseException if there was no response from the server.
1629     * @throws NotConnectedException if the XMPP connection is not connected.
1630     * @throws InterruptedException if the calling thread was interrupted.
1631     */
1632    public void revokeOwnership(Collection<? extends Jid> jids) throws XMPPErrorException, NoResponseException, NotConnectedException, InterruptedException {
1633        changeAffiliationByAdmin(jids, MUCAffiliation.admin);
1634    }
1635
1636    /**
1637     * Revokes ownership privileges from another user. The occupant that loses ownership
1638     * privileges will become an administrator. Room owners may revoke ownership privileges.
1639     * Some room implementations will not allow to grant ownership privileges to other users.
1640     *
1641     * @param jid the bare XMPP user ID of the user to revoke ownership (e.g. "user@host.org").
1642     * @throws XMPPErrorException if an error occurs revoking ownership privileges from a user.
1643     * @throws NoResponseException if there was no response from the server.
1644     * @throws NotConnectedException if the XMPP connection is not connected.
1645     * @throws InterruptedException if the calling thread was interrupted.
1646     */
1647    public void revokeOwnership(Jid jid) throws XMPPErrorException, NoResponseException, NotConnectedException, InterruptedException {
1648        changeAffiliationByAdmin(jid, MUCAffiliation.admin, null);
1649    }
1650
1651    /**
1652     * Grants administrator privileges to other users. Room owners may grant administrator
1653     * privileges to a member or unaffiliated user. An administrator is allowed to perform
1654     * administrative functions such as banning users and edit moderator list.
1655     *
1656     * @param jids the bare XMPP user IDs of the users to grant administrator privileges.
1657     * @throws XMPPErrorException if an error occurs granting administrator privileges to a user.
1658     * @throws NoResponseException if there was no response from the server.
1659     * @throws NotConnectedException if the XMPP connection is not connected.
1660     * @throws InterruptedException if the calling thread was interrupted.
1661     */
1662    public void grantAdmin(Collection<? extends Jid> jids) throws XMPPErrorException, NoResponseException, NotConnectedException, InterruptedException {
1663        changeAffiliationByAdmin(jids, MUCAffiliation.admin);
1664    }
1665
1666    /**
1667     * Grants administrator privileges to another user. Room owners may grant administrator
1668     * privileges to a member or unaffiliated user. An administrator is allowed to perform
1669     * administrative functions such as banning users and edit moderator list.
1670     *
1671     * @param jid the bare XMPP user ID of the user to grant administrator privileges
1672     * (e.g. "user@host.org").
1673     * @throws XMPPErrorException if an error occurs granting administrator privileges to a user.
1674     * @throws NoResponseException if there was no response from the server.
1675     * @throws NotConnectedException if the XMPP connection is not connected.
1676     * @throws InterruptedException if the calling thread was interrupted.
1677     */
1678    public void grantAdmin(Jid jid) throws XMPPErrorException, NoResponseException, NotConnectedException, InterruptedException {
1679        changeAffiliationByAdmin(jid, MUCAffiliation.admin);
1680    }
1681
1682    /**
1683     * Revokes administrator privileges from users. The occupant that loses administrator
1684     * privileges will become a member. Room owners may revoke administrator privileges from
1685     * a member or unaffiliated user.
1686     *
1687     * @param jids the bare XMPP user IDs of the user to revoke administrator privileges.
1688     * @throws XMPPErrorException if an error occurs revoking administrator privileges from a user.
1689     * @throws NoResponseException if there was no response from the server.
1690     * @throws NotConnectedException if the XMPP connection is not connected.
1691     * @throws InterruptedException if the calling thread was interrupted.
1692     */
1693    public void revokeAdmin(Collection<? extends Jid> jids) throws XMPPErrorException, NoResponseException, NotConnectedException, InterruptedException {
1694        changeAffiliationByAdmin(jids, MUCAffiliation.admin);
1695    }
1696
1697    /**
1698     * Revokes administrator privileges from a user. The occupant that loses administrator
1699     * privileges will become a member. Room owners may revoke administrator privileges from
1700     * a member or unaffiliated user.
1701     *
1702     * @param jid the bare XMPP user ID of the user to revoke administrator privileges
1703     * (e.g. "user@host.org").
1704     * @throws XMPPErrorException if an error occurs revoking administrator privileges from a user.
1705     * @throws NoResponseException if there was no response from the server.
1706     * @throws NotConnectedException if the XMPP connection is not connected.
1707     * @throws InterruptedException if the calling thread was interrupted.
1708     */
1709    public void revokeAdmin(EntityJid jid) throws XMPPErrorException, NoResponseException, NotConnectedException, InterruptedException {
1710        changeAffiliationByAdmin(jid, MUCAffiliation.member);
1711    }
1712
1713    /**
1714     * Tries to change the affiliation with an 'muc#admin' namespace
1715     *
1716     * @param jid TODO javadoc me please
1717     * @param affiliation TODO javadoc me please
1718     * @throws XMPPErrorException if there was an XMPP error returned.
1719     * @throws NoResponseException if there was no response from the remote entity.
1720     * @throws NotConnectedException if the XMPP connection is not connected.
1721     * @throws InterruptedException if the calling thread was interrupted.
1722     */
1723    private void changeAffiliationByAdmin(Jid jid, MUCAffiliation affiliation)
1724                    throws NoResponseException, XMPPErrorException,
1725                    NotConnectedException, InterruptedException {
1726        changeAffiliationByAdmin(jid, affiliation, null);
1727    }
1728
1729    /**
1730     * Tries to change the affiliation with an 'muc#admin' namespace
1731     *
1732     * @param jid TODO javadoc me please
1733     * @param affiliation TODO javadoc me please
1734     * @param reason the reason for the affiliation change (optional)
1735     * @throws XMPPErrorException if there was an XMPP error returned.
1736     * @throws NoResponseException if there was no response from the remote entity.
1737     * @throws NotConnectedException if the XMPP connection is not connected.
1738     * @throws InterruptedException if the calling thread was interrupted.
1739     */
1740    private void changeAffiliationByAdmin(Jid jid, MUCAffiliation affiliation, String reason) throws NoResponseException, XMPPErrorException, NotConnectedException, InterruptedException {
1741        MUCAdmin iq = new MUCAdmin();
1742        iq.setTo(room);
1743        iq.setType(IQ.Type.set);
1744        // Set the new affiliation.
1745        MUCItem item = new MUCItem(affiliation, jid, reason);
1746        iq.addItem(item);
1747
1748        connection.sendIqRequestAndWaitForResponse(iq);
1749    }
1750
1751    private void changeAffiliationByAdmin(Collection<? extends Jid> jids, MUCAffiliation affiliation)
1752                    throws NoResponseException, XMPPErrorException, NotConnectedException, InterruptedException {
1753        MUCAdmin iq = new MUCAdmin();
1754        iq.setTo(room);
1755        iq.setType(IQ.Type.set);
1756        for (Jid jid : jids) {
1757            // Set the new affiliation.
1758            MUCItem item = new MUCItem(affiliation, jid);
1759            iq.addItem(item);
1760        }
1761
1762        connection.sendIqRequestAndWaitForResponse(iq);
1763    }
1764
1765    private void changeRole(Resourcepart nickname, MUCRole role, String reason) throws NoResponseException, XMPPErrorException, NotConnectedException, InterruptedException {
1766        MUCAdmin iq = new MUCAdmin();
1767        iq.setTo(room);
1768        iq.setType(IQ.Type.set);
1769        // Set the new role.
1770        MUCItem item = new MUCItem(role, nickname, reason);
1771        iq.addItem(item);
1772
1773        connection.sendIqRequestAndWaitForResponse(iq);
1774    }
1775
1776    private void changeRole(Collection<Resourcepart> nicknames, MUCRole role) throws NoResponseException, XMPPErrorException, NotConnectedException, InterruptedException  {
1777        MUCAdmin iq = new MUCAdmin();
1778        iq.setTo(room);
1779        iq.setType(IQ.Type.set);
1780        for (Resourcepart nickname : nicknames) {
1781            // Set the new role.
1782            MUCItem item = new MUCItem(role, nickname);
1783            iq.addItem(item);
1784        }
1785
1786        connection.sendIqRequestAndWaitForResponse(iq);
1787    }
1788
1789    /**
1790     * Returns the number of occupants in the group chat.<p>
1791     *
1792     * Note: this value will only be accurate after joining the group chat, and
1793     * may fluctuate over time. If you query this value directly after joining the
1794     * group chat it may not be accurate, as it takes a certain amount of time for
1795     * the server to send all presence packets to this client.
1796     *
1797     * @return the number of occupants in the group chat.
1798     */
1799    public int getOccupantsCount() {
1800        return occupantsMap.size();
1801    }
1802
1803    /**
1804     * Returns an List  for the list of fully qualified occupants
1805     * in the group chat. For example, "conference@chat.jivesoftware.com/SomeUser".
1806     * Typically, a client would only display the nickname of the occupant. To
1807     * get the nickname from the fully qualified name, use the
1808     * {@link org.jxmpp.util.XmppStringUtils#parseResource(String)} method.
1809     * Note: this value will only be accurate after joining the group chat, and may
1810     * fluctuate over time.
1811     *
1812     * @return a List of the occupants in the group chat.
1813     */
1814    public List<EntityFullJid> getOccupants() {
1815        return new ArrayList<>(occupantsMap.keySet());
1816    }
1817
1818    /**
1819     * Returns the presence info for a particular user, or <code>null</code> if the user
1820     * is not in the room.<p>
1821     *
1822     * @param user the room occupant to search for his presence. The format of user must
1823     * be: roomName@service/nickname (e.g. darkcave@macbeth.shakespeare.lit/thirdwitch).
1824     * @return the occupant's current presence, or <code>null</code> if the user is unavailable
1825     *      or if no presence information is available.
1826     */
1827    public Presence getOccupantPresence(EntityFullJid user) {
1828        return occupantsMap.get(user);
1829    }
1830
1831    /**
1832     * Returns the Occupant information for a particular occupant, or <code>null</code> if the
1833     * user is not in the room. The Occupant object may include information such as full
1834     * JID of the user as well as the role and affiliation of the user in the room.<p>
1835     *
1836     * @param user the room occupant to search for his presence. The format of user must
1837     * be: roomName@service/nickname (e.g. darkcave@macbeth.shakespeare.lit/thirdwitch).
1838     * @return the Occupant or <code>null</code> if the user is unavailable (i.e. not in the room).
1839     */
1840    public Occupant getOccupant(EntityFullJid user) {
1841        Presence presence = getOccupantPresence(user);
1842        if (presence != null) {
1843            return new Occupant(presence);
1844        }
1845        return null;
1846    }
1847
1848    /**
1849     * Adds a stanza listener that will be notified of any new Presence packets
1850     * sent to the group chat. Using a listener is a suitable way to know when the list
1851     * of occupants should be re-loaded due to any changes.
1852     *
1853     * @param listener a stanza listener that will be notified of any presence packets
1854     *      sent to the group chat.
1855     * @return true if the listener was not already added.
1856     */
1857    public boolean addParticipantListener(PresenceListener listener) {
1858        return presenceListeners.add(listener);
1859    }
1860
1861    /**
1862     * Removes a stanza listener that was being notified of any new Presence packets
1863     * sent to the group chat.
1864     *
1865     * @param listener a stanza listener that was being notified of any presence packets
1866     *      sent to the group chat.
1867     * @return true if the listener was removed, otherwise the listener was not added previously.
1868     */
1869    public boolean removeParticipantListener(PresenceListener listener) {
1870        return presenceListeners.remove(listener);
1871    }
1872
1873    /**
1874     * Returns a list of <code>Affiliate</code> with the room owners.
1875     *
1876     * @return a list of <code>Affiliate</code> with the room owners.
1877     * @throws XMPPErrorException if you don't have enough privileges to get this information.
1878     * @throws NoResponseException if there was no response from the server.
1879     * @throws NotConnectedException if the XMPP connection is not connected.
1880     * @throws InterruptedException if the calling thread was interrupted.
1881     */
1882    public List<Affiliate> getOwners() throws NoResponseException, XMPPErrorException, NotConnectedException, InterruptedException {
1883        return getAffiliatesByAdmin(MUCAffiliation.owner);
1884    }
1885
1886    /**
1887     * Returns a list of <code>Affiliate</code> with the room administrators.
1888     *
1889     * @return a list of <code>Affiliate</code> with the room administrators.
1890     * @throws XMPPErrorException if you don't have enough privileges to get this information.
1891     * @throws NoResponseException if there was no response from the server.
1892     * @throws NotConnectedException if the XMPP connection is not connected.
1893     * @throws InterruptedException if the calling thread was interrupted.
1894     */
1895    public List<Affiliate> getAdmins() throws NoResponseException, XMPPErrorException, NotConnectedException, InterruptedException {
1896        return getAffiliatesByAdmin(MUCAffiliation.admin);
1897    }
1898
1899    /**
1900     * Returns a list of <code>Affiliate</code> with the room members.
1901     *
1902     * @return a list of <code>Affiliate</code> with the room members.
1903     * @throws XMPPErrorException if you don't have enough privileges to get this information.
1904     * @throws NoResponseException if there was no response from the server.
1905     * @throws NotConnectedException if the XMPP connection is not connected.
1906     * @throws InterruptedException if the calling thread was interrupted.
1907     */
1908    public List<Affiliate> getMembers() throws NoResponseException, XMPPErrorException, NotConnectedException, InterruptedException  {
1909        return getAffiliatesByAdmin(MUCAffiliation.member);
1910    }
1911
1912    /**
1913     * Returns a list of <code>Affiliate</code> with the room outcasts.
1914     *
1915     * @return a list of <code>Affiliate</code> with the room outcasts.
1916     * @throws XMPPErrorException if you don't have enough privileges to get this information.
1917     * @throws NoResponseException if there was no response from the server.
1918     * @throws NotConnectedException if the XMPP connection is not connected.
1919     * @throws InterruptedException if the calling thread was interrupted.
1920     */
1921    public List<Affiliate> getOutcasts() throws NoResponseException, XMPPErrorException, NotConnectedException, InterruptedException {
1922        return getAffiliatesByAdmin(MUCAffiliation.outcast);
1923    }
1924
1925    /**
1926     * Returns a collection of <code>Affiliate</code> that have the specified room affiliation
1927     * sending a request in the admin namespace.
1928     *
1929     * @param affiliation the affiliation of the users in the room.
1930     * @return a collection of <code>Affiliate</code> that have the specified room affiliation.
1931     * @throws XMPPErrorException if you don't have enough privileges to get this information.
1932     * @throws NoResponseException if there was no response from the server.
1933     * @throws NotConnectedException if the XMPP connection is not connected.
1934     * @throws InterruptedException if the calling thread was interrupted.
1935     */
1936    private List<Affiliate> getAffiliatesByAdmin(MUCAffiliation affiliation) throws NoResponseException, XMPPErrorException, NotConnectedException, InterruptedException {
1937        MUCAdmin iq = new MUCAdmin();
1938        iq.setTo(room);
1939        iq.setType(IQ.Type.get);
1940        // Set the specified affiliation. This may request the list of owners/admins/members/outcasts.
1941        MUCItem item = new MUCItem(affiliation);
1942        iq.addItem(item);
1943
1944        MUCAdmin answer = (MUCAdmin) connection.sendIqRequestAndWaitForResponse(iq);
1945
1946        // Get the list of affiliates from the server's answer
1947        List<Affiliate> affiliates = new ArrayList<Affiliate>();
1948        for (MUCItem mucadminItem : answer.getItems()) {
1949            affiliates.add(new Affiliate(mucadminItem));
1950        }
1951        return affiliates;
1952    }
1953
1954    /**
1955     * Returns a list of <code>Occupant</code> with the room moderators.
1956     *
1957     * @return a list of <code>Occupant</code> with the room moderators.
1958     * @throws XMPPErrorException if you don't have enough privileges to get this information.
1959     * @throws NoResponseException if there was no response from the server.
1960     * @throws NotConnectedException if the XMPP connection is not connected.
1961     * @throws InterruptedException if the calling thread was interrupted.
1962     */
1963    public List<Occupant> getModerators() throws NoResponseException, XMPPErrorException, NotConnectedException, InterruptedException {
1964        return getOccupants(MUCRole.moderator);
1965    }
1966
1967    /**
1968     * Returns a list of <code>Occupant</code> with the room participants.
1969     *
1970     * @return a list of <code>Occupant</code> with the room participants.
1971     * @throws XMPPErrorException if you don't have enough privileges to get this information.
1972     * @throws NoResponseException if there was no response from the server.
1973     * @throws NotConnectedException if the XMPP connection is not connected.
1974     * @throws InterruptedException if the calling thread was interrupted.
1975     */
1976    public List<Occupant> getParticipants() throws NoResponseException, XMPPErrorException, NotConnectedException, InterruptedException {
1977        return getOccupants(MUCRole.participant);
1978    }
1979
1980    /**
1981     * Returns a list of <code>Occupant</code> that have the specified room role.
1982     *
1983     * @param role the role of the occupant in the room.
1984     * @return a list of <code>Occupant</code> that have the specified room role.
1985     * @throws XMPPErrorException if an error occurred while performing the request to the server or you
1986     *         don't have enough privileges to get this information.
1987     * @throws NoResponseException if there was no response from the server.
1988     * @throws NotConnectedException if the XMPP connection is not connected.
1989     * @throws InterruptedException if the calling thread was interrupted.
1990     */
1991    private List<Occupant> getOccupants(MUCRole role) throws NoResponseException, XMPPErrorException, NotConnectedException, InterruptedException {
1992        MUCAdmin iq = new MUCAdmin();
1993        iq.setTo(room);
1994        iq.setType(IQ.Type.get);
1995        // Set the specified role. This may request the list of moderators/participants.
1996        MUCItem item = new MUCItem(role);
1997        iq.addItem(item);
1998
1999        MUCAdmin answer = (MUCAdmin) connection.sendIqRequestAndWaitForResponse(iq);
2000        // Get the list of participants from the server's answer
2001        List<Occupant> participants = new ArrayList<Occupant>();
2002        for (MUCItem mucadminItem : answer.getItems()) {
2003            participants.add(new Occupant(mucadminItem));
2004        }
2005        return participants;
2006    }
2007
2008    /**
2009     * Sends a message to the chat room.
2010     *
2011     * @param text the text of the message to send.
2012     * @throws NotConnectedException if the XMPP connection is not connected.
2013     * @throws InterruptedException if the calling thread was interrupted.
2014     */
2015    public void sendMessage(String text) throws NotConnectedException, InterruptedException {
2016        Message message = buildMessage()
2017                .setBody(text)
2018                .build();
2019        connection.sendStanza(message);
2020    }
2021
2022    /**
2023     * Returns a new Chat for sending private messages to a given room occupant.
2024     * The Chat's occupant address is the room's JID (i.e. roomName@service/nick). The server
2025     * service will change the 'from' address to the sender's room JID and delivering the message
2026     * to the intended recipient's full JID.
2027     *
2028     * @param occupant occupant unique room JID (e.g. 'darkcave@macbeth.shakespeare.lit/Paul').
2029     * @param listener the listener is a message listener that will handle messages for the newly
2030     * created chat.
2031     * @return new Chat for sending private messages to a given room occupant.
2032     */
2033    // TODO This should be made new not using chat.Chat. Private MUC chats are different from XMPP-IM 1:1 chats in to many ways.
2034    // API sketch: PrivateMucChat createPrivateChat(Resourcepart nick)
2035    @SuppressWarnings("deprecation")
2036    public org.jivesoftware.smack.chat.Chat createPrivateChat(EntityFullJid occupant, ChatMessageListener listener) {
2037        return org.jivesoftware.smack.chat.ChatManager.getInstanceFor(connection).createChat(occupant, listener);
2038    }
2039
2040    /**
2041     * Creates a new Message to send to the chat room.
2042     *
2043     * @return a new Message addressed to the chat room.
2044     * @deprecated use {@link #buildMessage()} instead.
2045     */
2046    @Deprecated
2047    // TODO: Remove when stanza builder is ready.
2048    public Message createMessage() {
2049        return connection.getStanzaFactory().buildMessageStanza()
2050                .ofType(Message.Type.groupchat)
2051                .to(room)
2052                .build();
2053    }
2054
2055    /**
2056     * Constructs a new message builder for messages send to this MUC room.
2057     *
2058     * @return a new message builder.
2059     */
2060    public MessageBuilder buildMessage() {
2061        return connection.getStanzaFactory()
2062                .buildMessageStanza()
2063                .ofType(Message.Type.groupchat)
2064                .to(room)
2065                ;
2066    }
2067
2068    /**
2069     * Sends a Message to the chat room.
2070     *
2071     * @param message the message.
2072     * @throws NotConnectedException if the XMPP connection is not connected.
2073     * @throws InterruptedException if the calling thread was interrupted.
2074     * @deprecated use {@link #sendMessage(MessageBuilder)} instead.
2075     */
2076    @Deprecated
2077    // TODO: Remove in Smack 4.5.
2078    public void sendMessage(Message message) throws NotConnectedException, InterruptedException {
2079        sendMessage(message.asBuilder());
2080    }
2081
2082    /**
2083     * Sends a Message to the chat room.
2084     *
2085     * @param messageBuilder the message.
2086     * @return a read-only view of the send message.
2087     * @throws NotConnectedException if the XMPP connection is not connected.
2088     * @throws InterruptedException if the calling thread was interrupted.
2089     */
2090    public MessageView sendMessage(MessageBuilder messageBuilder) throws NotConnectedException, InterruptedException {
2091        for (MucMessageInterceptor interceptor : messageInterceptors) {
2092            interceptor.intercept(messageBuilder, this);
2093        }
2094
2095        Message message = messageBuilder.to(room).ofType(Message.Type.groupchat).build();
2096        connection.sendStanza(message);
2097        return message;
2098    }
2099
2100    /**
2101    * Polls for and returns the next message, or <code>null</code> if there isn't
2102    * a message immediately available. This method provides significantly different
2103    * functionalty than the {@link #nextMessage()} method since it's non-blocking.
2104    * In other words, the method call will always return immediately, whereas the
2105    * nextMessage method will return only when a message is available (or after
2106    * a specific timeout).
2107    *
2108    * @return the next message if one is immediately available and
2109    *      <code>null</code> otherwise.
2110     * @throws MucNotJoinedException if not joined to the Multi-User Chat.
2111    */
2112    public Message pollMessage() throws MucNotJoinedException {
2113        if (messageCollector == null) {
2114            throw new MucNotJoinedException(this);
2115        }
2116        return messageCollector.pollResult();
2117    }
2118
2119    /**
2120     * Returns the next available message in the chat. The method call will block
2121     * (not return) until a message is available.
2122     *
2123     * @return the next message.
2124     * @throws MucNotJoinedException if not joined to the Multi-User Chat.
2125     * @throws InterruptedException if the calling thread was interrupted.
2126     */
2127    public Message nextMessage() throws MucNotJoinedException, InterruptedException {
2128        if (messageCollector == null) {
2129            throw new MucNotJoinedException(this);
2130        }
2131        return  messageCollector.nextResultBlockForever();
2132    }
2133
2134    /**
2135     * Returns the next available message in the chat. The method call will block
2136     * (not return) until a stanza is available or the <code>timeout</code> has elapased.
2137     * If the timeout elapses without a result, <code>null</code> will be returned.
2138     *
2139     * @param timeout the maximum amount of time to wait for the next message.
2140     * @return the next message, or <code>null</code> if the timeout elapses without a
2141     *      message becoming available.
2142     * @throws MucNotJoinedException if not joined to the Multi-User Chat.
2143     * @throws InterruptedException if the calling thread was interrupted.
2144     */
2145    public Message nextMessage(long timeout) throws MucNotJoinedException, InterruptedException {
2146        if (messageCollector == null) {
2147            throw new MucNotJoinedException(this);
2148        }
2149        return messageCollector.nextResult(timeout);
2150    }
2151
2152    /**
2153     * Adds a stanza listener that will be notified of any new messages in the
2154     * group chat. Only "group chat" messages addressed to this group chat will
2155     * be delivered to the listener. If you wish to listen for other packets
2156     * that may be associated with this group chat, you should register a
2157     * PacketListener directly with the XMPPConnection with the appropriate
2158     * PacketListener.
2159     *
2160     * @param listener a stanza listener.
2161     * @return true if the listener was not already added.
2162     */
2163    public boolean addMessageListener(MessageListener listener) {
2164        return messageListeners.add(listener);
2165    }
2166
2167    /**
2168     * Removes a stanza listener that was being notified of any new messages in the
2169     * multi user chat. Only "group chat" messages addressed to this multi user chat were
2170     * being delivered to the listener.
2171     *
2172     * @param listener a stanza listener.
2173     * @return true if the listener was removed, otherwise the listener was not added previously.
2174     */
2175    public boolean removeMessageListener(MessageListener listener) {
2176        return messageListeners.remove(listener);
2177    }
2178
2179    public boolean addMessageInterceptor(MucMessageInterceptor interceptor) {
2180        return messageInterceptors.add(interceptor);
2181    }
2182
2183    public boolean removeMessageInterceptor(MucMessageInterceptor interceptor) {
2184        return messageInterceptors.remove(interceptor);
2185    }
2186
2187    /**
2188     * Changes the subject within the room. As a default, only users with a role of "moderator"
2189     * are allowed to change the subject in a room. Although some rooms may be configured to
2190     * allow a mere participant or even a visitor to change the subject.
2191     *
2192     * @param subject the new room's subject to set.
2193     * @throws XMPPErrorException if someone without appropriate privileges attempts to change the
2194     *          room subject will throw an error with code 403 (i.e. Forbidden)
2195     * @throws NoResponseException if there was no response from the server.
2196     * @throws NotConnectedException if the XMPP connection is not connected.
2197     * @throws InterruptedException if the calling thread was interrupted.
2198     */
2199    public void changeSubject(final String subject) throws NoResponseException, XMPPErrorException, NotConnectedException, InterruptedException {
2200        MessageBuilder message = buildMessage();
2201        message.setSubject(subject);
2202        // Wait for an error or confirmation message back from the server.
2203        StanzaFilter responseFilter = new AndFilter(fromRoomGroupchatFilter, new StanzaFilter() {
2204            @Override
2205            public boolean accept(Stanza packet) {
2206                Message msg = (Message) packet;
2207                return subject.equals(msg.getSubject());
2208            }
2209        });
2210        StanzaCollector response = connection.createStanzaCollectorAndSend(responseFilter, message.build());
2211        // Wait up to a certain number of seconds for a reply.
2212        response.nextResultOrThrow();
2213    }
2214
2215    /**
2216     * Remove the connection callbacks (PacketListener, PacketInterceptor, StanzaCollector) used by this MUC from the
2217     * connection.
2218     */
2219    private void removeConnectionCallbacks() {
2220        connection.removeStanzaListener(messageListener);
2221        connection.removeStanzaListener(presenceListener);
2222        connection.removeStanzaListener(subjectListener);
2223        connection.removeStanzaListener(declinesListener);
2224        connection.removePresenceInterceptor(presenceInterceptor);
2225        if (messageCollector != null) {
2226            messageCollector.cancel();
2227            messageCollector = null;
2228        }
2229    }
2230
2231    /**
2232     * Remove all callbacks and resources necessary when the user has left the room for some reason.
2233     */
2234    private synchronized void userHasLeft() {
2235        // We do not reset nickname here, in case this method has been called erroneously, it should still be possible
2236        // to call leave() in order to resync the state. And leave() requires the nickname to send the unsubscribe
2237        // presence.
2238        occupantsMap.clear();
2239        myRoomJid = null;
2240        // Update the list of joined rooms
2241        multiUserChatManager.removeJoinedRoom(room);
2242        removeConnectionCallbacks();
2243    }
2244
2245    /**
2246     * Adds a listener that will be notified of changes in your status in the room
2247     * such as the user being kicked, banned, or granted admin permissions.
2248     *
2249     * @param listener a user status listener.
2250     * @return true if the user status listener was not already added.
2251     */
2252    public boolean addUserStatusListener(UserStatusListener listener) {
2253        return userStatusListeners.add(listener);
2254    }
2255
2256    /**
2257     * Removes a listener that was being notified of changes in your status in the room
2258     * such as the user being kicked, banned, or granted admin permissions.
2259     *
2260     * @param listener a user status listener.
2261     * @return true if the listener was registered and is now removed.
2262     */
2263    public boolean removeUserStatusListener(UserStatusListener listener) {
2264        return userStatusListeners.remove(listener);
2265    }
2266
2267    /**
2268     * Adds a listener that will be notified of changes in occupants status in the room
2269     * such as the user being kicked, banned, or granted admin permissions.
2270     *
2271     * @param listener a participant status listener.
2272     * @return true if the listener was not already added.
2273     */
2274    public boolean addParticipantStatusListener(ParticipantStatusListener listener) {
2275        return participantStatusListeners.add(listener);
2276    }
2277
2278    /**
2279     * Removes a listener that was being notified of changes in occupants status in the room
2280     * such as the user being kicked, banned, or granted admin permissions.
2281     *
2282     * @param listener a participant status listener.
2283     * @return true if the listener was registered and is now removed.
2284     */
2285    public boolean removeParticipantStatusListener(ParticipantStatusListener listener) {
2286        return participantStatusListeners.remove(listener);
2287    }
2288
2289    /**
2290     * Fires notification events if the role of a room occupant has changed. If the occupant that
2291     * changed his role is your occupant then the <code>UserStatusListeners</code> added to this
2292     * <code>MultiUserChat</code> will be fired. On the other hand, if the occupant that changed
2293     * his role is not yours then the <code>ParticipantStatusListeners</code> added to this
2294     * <code>MultiUserChat</code> will be fired. The following table shows the events that will
2295     * be fired depending on the previous and new role of the occupant.
2296     *
2297     * <pre>
2298     * <table border="1">
2299     * <tr><td><b>Old</b></td><td><b>New</b></td><td><b>Events</b></td></tr>
2300     *
2301     * <tr><td>None</td><td>Visitor</td><td>--</td></tr>
2302     * <tr><td>Visitor</td><td>Participant</td><td>voiceGranted</td></tr>
2303     * <tr><td>Participant</td><td>Moderator</td><td>moderatorGranted</td></tr>
2304     *
2305     * <tr><td>None</td><td>Participant</td><td>voiceGranted</td></tr>
2306     * <tr><td>None</td><td>Moderator</td><td>voiceGranted + moderatorGranted</td></tr>
2307     * <tr><td>Visitor</td><td>Moderator</td><td>voiceGranted + moderatorGranted</td></tr>
2308     *
2309     * <tr><td>Moderator</td><td>Participant</td><td>moderatorRevoked</td></tr>
2310     * <tr><td>Participant</td><td>Visitor</td><td>voiceRevoked</td></tr>
2311     * <tr><td>Visitor</td><td>None</td><td>kicked</td></tr>
2312     *
2313     * <tr><td>Moderator</td><td>Visitor</td><td>voiceRevoked + moderatorRevoked</td></tr>
2314     * <tr><td>Moderator</td><td>None</td><td>kicked</td></tr>
2315     * <tr><td>Participant</td><td>None</td><td>kicked</td></tr>
2316     * </table>
2317     * </pre>
2318     *
2319     * @param oldRole the previous role of the user in the room before receiving the new presence
2320     * @param newRole the new role of the user in the room after receiving the new presence
2321     * @param isUserModification whether the received presence is about your user in the room or not
2322     * @param from the occupant whose role in the room has changed
2323     * (e.g. room@conference.jabber.org/nick).
2324     */
2325    private void checkRoleModifications(
2326        MUCRole oldRole,
2327        MUCRole newRole,
2328        boolean isUserModification,
2329        EntityFullJid from) {
2330        // Voice was granted to a visitor
2331        if ((MUCRole.visitor.equals(oldRole) || MUCRole.none.equals(oldRole))
2332            && MUCRole.participant.equals(newRole)) {
2333            if (isUserModification) {
2334                for (UserStatusListener listener : userStatusListeners) {
2335                    listener.voiceGranted();
2336                }
2337            }
2338            else {
2339                for (ParticipantStatusListener listener : participantStatusListeners) {
2340                    listener.voiceGranted(from);
2341                }
2342            }
2343        }
2344        // The participant's voice was revoked from the room
2345        else if (
2346            MUCRole.participant.equals(oldRole)
2347                && (MUCRole.visitor.equals(newRole) || MUCRole.none.equals(newRole))) {
2348            if (isUserModification) {
2349                for (UserStatusListener listener : userStatusListeners) {
2350                    listener.voiceRevoked();
2351                }
2352            }
2353            else {
2354                for (ParticipantStatusListener listener : participantStatusListeners) {
2355                    listener.voiceRevoked(from);
2356                }
2357            }
2358        }
2359        // Moderator privileges were granted to a participant
2360        if (!MUCRole.moderator.equals(oldRole) && MUCRole.moderator.equals(newRole)) {
2361            if (MUCRole.visitor.equals(oldRole) || MUCRole.none.equals(oldRole)) {
2362                if (isUserModification) {
2363                    for (UserStatusListener listener : userStatusListeners) {
2364                        listener.voiceGranted();
2365                    }
2366                }
2367                else {
2368                    for (ParticipantStatusListener listener : participantStatusListeners) {
2369                        listener.voiceGranted(from);
2370                    }
2371                }
2372            }
2373            if (isUserModification) {
2374                for (UserStatusListener listener : userStatusListeners) {
2375                    listener.moderatorGranted();
2376                }
2377            }
2378            else {
2379                for (ParticipantStatusListener listener : participantStatusListeners) {
2380                    listener.moderatorGranted(from);
2381                }
2382            }
2383        }
2384        // Moderator privileges were revoked from a participant
2385        else if (MUCRole.moderator.equals(oldRole) && !MUCRole.moderator.equals(newRole)) {
2386            if (MUCRole.visitor.equals(newRole) || MUCRole.none.equals(newRole)) {
2387                if (isUserModification) {
2388                    for (UserStatusListener listener : userStatusListeners) {
2389                        listener.voiceRevoked();
2390                    }
2391                }
2392                else {
2393                    for (ParticipantStatusListener listener : participantStatusListeners) {
2394                        listener.voiceRevoked(from);
2395                    }
2396                }
2397            }
2398            if (isUserModification) {
2399                for (UserStatusListener listener : userStatusListeners) {
2400                    listener.moderatorRevoked();
2401                }
2402            }
2403            else {
2404                for (ParticipantStatusListener listener : participantStatusListeners) {
2405                    listener.moderatorRevoked(from);
2406                }
2407            }
2408        }
2409    }
2410
2411    /**
2412     * Fires notification events if the affiliation of a room occupant has changed. If the
2413     * occupant that changed his affiliation is your occupant then the
2414     * <code>UserStatusListeners</code> added to this <code>MultiUserChat</code> will be fired.
2415     * On the other hand, if the occupant that changed his affiliation is not yours then the
2416     * <code>ParticipantStatusListeners</code> added to this <code>MultiUserChat</code> will be
2417     * fired. The following table shows the events that will be fired depending on the previous
2418     * and new affiliation of the occupant.
2419     *
2420     * <pre>
2421     * <table border="1">
2422     * <tr><td><b>Old</b></td><td><b>New</b></td><td><b>Events</b></td></tr>
2423     *
2424     * <tr><td>None</td><td>Member</td><td>membershipGranted</td></tr>
2425     * <tr><td>Member</td><td>Admin</td><td>membershipRevoked + adminGranted</td></tr>
2426     * <tr><td>Admin</td><td>Owner</td><td>adminRevoked + ownershipGranted</td></tr>
2427     *
2428     * <tr><td>None</td><td>Admin</td><td>adminGranted</td></tr>
2429     * <tr><td>None</td><td>Owner</td><td>ownershipGranted</td></tr>
2430     * <tr><td>Member</td><td>Owner</td><td>membershipRevoked + ownershipGranted</td></tr>
2431     *
2432     * <tr><td>Owner</td><td>Admin</td><td>ownershipRevoked + adminGranted</td></tr>
2433     * <tr><td>Admin</td><td>Member</td><td>adminRevoked + membershipGranted</td></tr>
2434     * <tr><td>Member</td><td>None</td><td>membershipRevoked</td></tr>
2435     *
2436     * <tr><td>Owner</td><td>Member</td><td>ownershipRevoked + membershipGranted</td></tr>
2437     * <tr><td>Owner</td><td>None</td><td>ownershipRevoked</td></tr>
2438     * <tr><td>Admin</td><td>None</td><td>adminRevoked</td></tr>
2439     * <tr><td><i>Anyone</i></td><td>Outcast</td><td>banned</td></tr>
2440     * </table>
2441     * </pre>
2442     *
2443     * @param oldAffiliation the previous affiliation of the user in the room before receiving the
2444     * new presence
2445     * @param newAffiliation the new affiliation of the user in the room after receiving the new
2446     * presence
2447     * @param isUserModification whether the received presence is about your user in the room or not
2448     * @param from the occupant whose role in the room has changed
2449     * (e.g. room@conference.jabber.org/nick).
2450     */
2451    private void checkAffiliationModifications(
2452        MUCAffiliation oldAffiliation,
2453        MUCAffiliation newAffiliation,
2454        boolean isUserModification,
2455        EntityFullJid from) {
2456        // First check for revoked affiliation and then for granted affiliations. The idea is to
2457        // first fire the "revoke" events and then fire the "grant" events.
2458
2459        // The user's ownership to the room was revoked
2460        if (MUCAffiliation.owner.equals(oldAffiliation) && !MUCAffiliation.owner.equals(newAffiliation)) {
2461            if (isUserModification) {
2462                for (UserStatusListener listener : userStatusListeners) {
2463                    listener.ownershipRevoked();
2464                }
2465            }
2466            else {
2467                for (ParticipantStatusListener listener : participantStatusListeners) {
2468                    listener.ownershipRevoked(from);
2469                }
2470            }
2471        }
2472        // The user's administrative privileges to the room were revoked
2473        else if (MUCAffiliation.admin.equals(oldAffiliation) && !MUCAffiliation.admin.equals(newAffiliation)) {
2474            if (isUserModification) {
2475                for (UserStatusListener listener : userStatusListeners) {
2476                    listener.adminRevoked();
2477                }
2478            }
2479            else {
2480                for (ParticipantStatusListener listener : participantStatusListeners) {
2481                    listener.adminRevoked(from);
2482                }
2483            }
2484        }
2485        // The user's membership to the room was revoked
2486        else if (MUCAffiliation.member.equals(oldAffiliation) && !MUCAffiliation.member.equals(newAffiliation)) {
2487            if (isUserModification) {
2488                for (UserStatusListener listener : userStatusListeners) {
2489                    listener.membershipRevoked();
2490                }
2491            }
2492            else {
2493                for (ParticipantStatusListener listener : participantStatusListeners) {
2494                    listener.membershipRevoked(from);
2495                }
2496            }
2497        }
2498
2499        // The user was granted ownership to the room
2500        if (!MUCAffiliation.owner.equals(oldAffiliation) && MUCAffiliation.owner.equals(newAffiliation)) {
2501            if (isUserModification) {
2502                for (UserStatusListener listener : userStatusListeners) {
2503                    listener.ownershipGranted();
2504                }
2505            }
2506            else {
2507                for (ParticipantStatusListener listener : participantStatusListeners) {
2508                    listener.ownershipGranted(from);
2509                }
2510            }
2511        }
2512        // The user was granted administrative privileges to the room
2513        else if (!MUCAffiliation.admin.equals(oldAffiliation) && MUCAffiliation.admin.equals(newAffiliation)) {
2514            if (isUserModification) {
2515                for (UserStatusListener listener : userStatusListeners) {
2516                    listener.adminGranted();
2517                }
2518            }
2519            else {
2520                for (ParticipantStatusListener listener : participantStatusListeners) {
2521                    listener.adminGranted(from);
2522                }
2523            }
2524        }
2525        // The user was granted membership to the room
2526        else if (!MUCAffiliation.member.equals(oldAffiliation) && MUCAffiliation.member.equals(newAffiliation)) {
2527            if (isUserModification) {
2528                for (UserStatusListener listener : userStatusListeners) {
2529                    listener.membershipGranted();
2530                }
2531            }
2532            else {
2533                for (ParticipantStatusListener listener : participantStatusListeners) {
2534                    listener.membershipGranted(from);
2535                }
2536            }
2537        }
2538    }
2539
2540    /**
2541     * Fires events according to the received presence code.
2542     *
2543     * @param statusCodes TODO javadoc me please
2544     * @param isUserModification TODO javadoc me please
2545     * @param mucUser TODO javadoc me please
2546     * @param from TODO javadoc me please
2547     */
2548    private void checkPresenceCode(
2549        Set<Status> statusCodes,
2550        boolean isUserModification,
2551        MUCUser mucUser,
2552        EntityFullJid from) {
2553        // Check if an occupant was kicked from the room
2554        if (statusCodes.contains(Status.KICKED_307)) {
2555            // Check if this occupant was kicked
2556            if (isUserModification) {
2557                for (UserStatusListener listener : userStatusListeners) {
2558                    listener.kicked(mucUser.getItem().getActor(), mucUser.getItem().getReason());
2559                }
2560            }
2561            else {
2562                for (ParticipantStatusListener listener : participantStatusListeners) {
2563                    listener.kicked(from, mucUser.getItem().getActor(), mucUser.getItem().getReason());
2564                }
2565            }
2566        }
2567        // A user was banned from the room
2568        if (statusCodes.contains(Status.BANNED_301)) {
2569            // Check if this occupant was banned
2570            if (isUserModification) {
2571                for (UserStatusListener listener : userStatusListeners) {
2572                    listener.banned(mucUser.getItem().getActor(), mucUser.getItem().getReason());
2573                }
2574            }
2575            else {
2576                for (ParticipantStatusListener listener : participantStatusListeners) {
2577                    listener.banned(from, mucUser.getItem().getActor(), mucUser.getItem().getReason());
2578                }
2579            }
2580        }
2581        // A user's membership was revoked from the room
2582        if (statusCodes.contains(Status.REMOVED_AFFIL_CHANGE_321)) {
2583            // Check if this occupant's membership was revoked
2584            if (isUserModification) {
2585                for (UserStatusListener listener : userStatusListeners) {
2586                    listener.membershipRevoked();
2587                }
2588            }
2589        }
2590        // A occupant has changed his nickname in the room
2591        if (statusCodes.contains(Status.NEW_NICKNAME_303)) {
2592            for (ParticipantStatusListener listener : participantStatusListeners) {
2593                listener.nicknameChanged(from, mucUser.getItem().getNick());
2594            }
2595        }
2596    }
2597
2598    /**
2599     * Get the XMPP connection associated with this chat instance.
2600     *
2601     * @return the associated XMPP connection.
2602     * @since 4.3.0
2603     */
2604    public XMPPConnection getXmppConnection() {
2605        return connection;
2606    }
2607
2608    public boolean serviceSupportsStableIds() {
2609        return DiscoverInfo.nullSafeContainsFeature(mucServiceDiscoInfo, MultiUserChatConstants.STABLE_ID_FEATURE);
2610    }
2611
2612    @Override
2613    public String toString() {
2614        return "MUC: " + room + "(" + connection.getUser() + ")";
2615    }
2616}