Add MultiUserChat.leaveSync()

Fixes SMACK-848.

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

@@ -734,7 +734,12 @@ public class MultiUserChat {
         // If we've already joined the room, leave it before joining under a new
         // nickname.
         if (joined) {
-            leave();
+            try {
+                leaveSync();
+            }
+            catch (XMPPErrorException | NoResponseException | MucNotJoinedException e) {
+                LOGGER.log(Level.WARNING, "Could not leave MUC prior joining, assuming we are not joined", e);
+            }
         }
         enter(mucEnterConfiguration);
     }
@@ -775,6 +780,50 @@ public class MultiUserChat {
         connection.sendStanza(leavePresence);
     }
 
+    /**
+     * Leave the chat room.
+     *
+     * @return the leave presence as reflected by the MUC.
+     * @throws NotConnectedException
+     * @throws InterruptedException
+     * @throws XMPPErrorException
+     * @throws NoResponseException
+     * @throws MucNotJoinedException
+     */
+    public synchronized Presence leaveSync()
+                    throws NotConnectedException, InterruptedException, NoResponseException, XMPPErrorException, MucNotJoinedException {
+        //  Note that this method is intentionally not guarded by
+        // "if  (!joined) return" because it should be always be possible to leave the room in case the instance's
+        // state does not reflect the actual state.
+
+        // Reset occupant information first so that we are assume that we left the room even if sendStanza() would
+        // throw.
+        userHasLeft();
+
+        final EntityFullJid myRoomJid = this.myRoomJid;
+        if (myRoomJid == null) {
+            throw new MucNotJoinedException(this);
+        }
+
+        // We leave a room by sending a presence packet where the "to"
+        // field is in the form "roomName@service/nickname"
+        Presence leavePresence = new Presence(Presence.Type.unavailable);
+        leavePresence.setTo(myRoomJid);
+
+        StanzaFilter reflectedLeavePresenceFilter = new AndFilter(
+                        StanzaTypeFilter.PRESENCE,
+                        new StanzaIdFilter(leavePresence),
+                        new OrFilter(
+                                        new AndFilter(FromMatchesFilter.createFull(myRoomJid), PresenceTypeFilter.UNAVAILABLE, MUCUserStatusCodeFilter.STATUS_110_PRESENCE_TO_SELF),
+                                        new AndFilter(fromRoomFilter, PresenceTypeFilter.ERROR)
+                                    )
+                                );
+
+        Presence reflectedLeavePresence = connection.createStanzaCollectorAndSend(reflectedLeavePresenceFilter, leavePresence).nextResultOrThrow();
+
+        return reflectedLeavePresence;
+    }
+
     /**
      * Get a {@link MucConfigFormManager} to configure this room.
      * <p>

smack-integration-test/src/main/java/org/jivesoftware/smackx/muc/MultiUserChatIntegrationTest.java

@@ -16,6 +16,9 @@
  */
 package org.jivesoftware.smackx.muc;
 
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertTrue;
+
 import java.util.List;
 
 import org.jivesoftware.smack.MessageListener;
@@ -23,8 +26,12 @@ import org.jivesoftware.smack.SmackException.NoResponseException;
 import org.jivesoftware.smack.SmackException.NotConnectedException;
 import org.jivesoftware.smack.XMPPException.XMPPErrorException;
 import org.jivesoftware.smack.packet.Message;
+import org.jivesoftware.smack.packet.Presence;
 import org.jivesoftware.smack.util.StringUtils;
 import org.jivesoftware.smackx.muc.MultiUserChat.MucCreateConfigFormHandle;
+import org.jivesoftware.smackx.muc.MultiUserChatException.MucNotJoinedException;
+import org.jivesoftware.smackx.muc.MultiUserChatException.NotAMucServiceException;
+import org.jivesoftware.smackx.muc.packet.MUCUser;
 
 import org.igniterealtime.smack.inttest.AbstractSmackIntegrationTest;
 import org.igniterealtime.smack.inttest.SmackIntegrationTest;
@@ -36,6 +43,7 @@ import org.jxmpp.jid.EntityBareJid;
 import org.jxmpp.jid.impl.JidCreate;
 import org.jxmpp.jid.parts.Localpart;
 import org.jxmpp.jid.parts.Resourcepart;
+import org.jxmpp.stringprep.XmppStringprepException;
 
 public class MultiUserChatIntegrationTest extends AbstractSmackIntegrationTest {
 
@@ -61,6 +69,24 @@ public class MultiUserChatIntegrationTest extends AbstractSmackIntegrationTest {
         }
     }
 
+    @SmackIntegrationTest
+    public void mucJoinLeaveTest() throws XmppStringprepException, NotAMucServiceException, NoResponseException,
+            XMPPErrorException, NotConnectedException, InterruptedException, MucNotJoinedException {
+        EntityBareJid mucAddress = JidCreate.entityBareFrom(Localpart.from("smack-inttest-join-leave-" + randomString),
+                mucService.getDomain());
+
+        MultiUserChat muc = mucManagerOne.getMultiUserChat(mucAddress);
+
+        muc.join(Resourcepart.from("nick-one"));
+
+        Presence reflectedLeavePresence = muc.leaveSync();
+
+        MUCUser mucUser = MUCUser.from(reflectedLeavePresence);
+        assertNotNull(mucUser);
+
+        assertTrue(mucUser.getStatus().contains(MUCUser.Status.PRESENCE_TO_SELF_110));
+    }
+
     @SmackIntegrationTest
     public void mucTest() throws Exception {
         EntityBareJid mucAddress = JidCreate.entityBareFrom(Localpart.from("smack-inttest-" + randomString), mucService.getDomain());