Factored scene movement out into separate helper classes so that code can be a

bit more cleanly shared and the process of resolving zones and scenes and the
various fiddling done during a scene move can be more easily grokked.


git-svn-id: svn+ssh://src.earth.threerings.net/vilya/trunk@363 c613c5cb-e716-0410-b11b-feb51c14d237

src/java/com/threerings/whirled/server/AbstractSceneMoveHandler.java

@@ -0,0 +1,90 @@
+//
+// $Id$
+//
+// Vilya library - tools for developing networked games
+// Copyright (C) 2002-2007 Three Rings Design, Inc., All Rights Reserved
+// http://www.threerings.net/code/vilya/
+//
+// This library is free software; you can redistribute it and/or modify it
+// under the terms of the GNU Lesser General Public License as published
+// by the Free Software Foundation; either version 2.1 of the License, or
+// (at your option) any later version.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+// Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public
+// License along with this library; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+
+package com.threerings.whirled.server;
+
+import com.threerings.presents.client.InvocationService;
+import com.threerings.presents.data.InvocationMarshaller;
+import com.threerings.presents.server.InvocationException;
+
+import com.threerings.crowd.data.BodyObject;
+
+import com.threerings.whirled.client.SceneService;
+import com.threerings.whirled.data.SceneCodes;
+
+import com.threerings.whirled.Log;
+
+/**
+ * Handles the basics of moving a client into a new scene, which may involve resolution. Takes care
+ * of annoying edge cases like the client logging off before their target scene is resolved and can
+ * be extended to handle extra fun stuff.
+ */
+public abstract class AbstractSceneMoveHandler
+    implements SceneRegistry.ResolutionListener
+{
+    public AbstractSceneMoveHandler (BodyObject body, int sceneId, int version,
+                                     InvocationService.InvocationListener listener)
+    {
+        _body = body;
+        _sceneId = sceneId;
+        _version = version;
+        _listener = listener;
+    }
+
+    // from interface SceneRegistry.ResolutionListener
+    public void sceneWasResolved (SceneManager scmgr)
+    {
+        // make sure our caller is still around; under heavy load, clients might end their session
+        // while the scene is resolving
+        if (!_body.isActive()) {
+            Log.info("Abandoning scene move, client gone [who=" + _body.who()  +
+                     ", dest=" + scmgr.where() + "].");
+            InvocationMarshaller.setNoResponse(_listener);
+            return;
+        }
+
+        try {
+            effectSceneMove(scmgr);
+
+        } catch (InvocationException sfe) {
+            _listener.requestFailed(sfe.getMessage());
+
+        } catch (RuntimeException re) {
+            Log.logStackTrace(re);
+            _listener.requestFailed(SceneCodes.INTERNAL_ERROR);
+        }
+    }
+
+    // from interface SceneRegistry.ResolutionListener
+    public void sceneFailedToResolve (int sceneId, Exception reason)
+    {
+        Log.warning("Unable to resolve scene [sceneid=" + sceneId + ", reason=" + reason + "].");
+        _listener.requestFailed(SceneCodes.NO_SUCH_PLACE);
+    }
+
+    protected abstract void effectSceneMove (SceneManager scmgr)
+        throws InvocationException;
+
+    protected BodyObject _body;
+    protected int _sceneId;
+    protected int _version;
+    protected InvocationService.InvocationListener _listener;
+}

src/java/com/threerings/whirled/server/SceneMoveHandler.java

@@ -0,0 +1,76 @@
+//
+// $Id$
+//
+// Vilya library - tools for developing networked games
+// Copyright (C) 2002-2007 Three Rings Design, Inc., All Rights Reserved
+// http://www.threerings.net/code/vilya/
+//
+// This library is free software; you can redistribute it and/or modify it
+// under the terms of the GNU Lesser General Public License as published
+// by the Free Software Foundation; either version 2.1 of the License, or
+// (at your option) any later version.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+// Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public
+// License along with this library; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+
+package com.threerings.whirled.server;
+
+import com.threerings.presents.data.InvocationMarshaller;
+import com.threerings.presents.server.InvocationException;
+
+import com.threerings.crowd.data.BodyObject;
+import com.threerings.crowd.data.PlaceConfig;
+import com.threerings.crowd.server.CrowdServer;
+
+import com.threerings.whirled.client.SceneService;
+import com.threerings.whirled.data.SceneCodes;
+import com.threerings.whirled.data.SceneModel;
+import com.threerings.whirled.data.SceneUpdate;
+import com.threerings.whirled.data.ScenedBodyObject;
+
+/**
+ * Handles a simple scene to scene move.
+ */
+public class SceneMoveHandler extends AbstractSceneMoveHandler
+{
+    public SceneMoveHandler (BodyObject body, int sceneId, int sceneVer,
+                             SceneService.SceneMoveListener listener)
+    {
+        super(body, sceneId, sceneVer, listener);
+    }
+
+    @Override // from AbstractSceneMoveHandler
+    protected void effectSceneMove (SceneManager scmgr)
+        throws InvocationException
+    {
+        // move to the place object associated with this scene
+        int ploid = scmgr.getPlaceObject().getOid();
+        PlaceConfig config = CrowdServer.plreg.locprov.moveTo(_body, ploid);
+
+        // now that we've finally moved, we can update the user object with the new scene id
+        ((ScenedBodyObject)_body).setSceneId(scmgr.getScene().getId());
+
+        // check to see if they need a newer version of the scene data
+        SceneService.SceneMoveListener listener = (SceneService.SceneMoveListener)_listener;
+        SceneModel model = scmgr.getScene().getSceneModel();
+        if (_version != model.version) {
+            SceneUpdate[] updates = null;
+            if (_version < model.version) {
+                updates = scmgr.getUpdates(_version);
+            }
+            if (updates != null) {
+                listener.moveSucceededWithUpdates(ploid, config, updates);
+            } else {
+                listener.moveSucceededWithScene(ploid, config, model);
+            }
+        } else {
+            listener.moveSucceeded(ploid, config);
+        }
+    }
+}

src/java/com/threerings/whirled/server/SceneRegistry.java

@@ -221,72 +221,11 @@ public class SceneRegistry
     }
 
     // from interface SceneService
-    public void moveTo (ClientObject caller, int sceneId, final int sceneVer,
+    public void moveTo (ClientObject caller, int sceneId, int sceneVer,
-                        final SceneService.SceneMoveListener listener)
+                        SceneService.SceneMoveListener listener)
     {
-        final BodyObject source = (BodyObject)caller;
+        BodyObject body = (BodyObject)caller;
-
+        resolveScene(sceneId, new SceneMoveHandler(body, sceneId, sceneVer, listener));
-        // create a callback object to handle the resolution or failed resolution of the scene
-        SceneRegistry.ResolutionListener rl = null;
-        rl = new SceneRegistry.ResolutionListener() {
-            public void sceneWasResolved (SceneManager scmgr) {
-                // make sure our caller is still around; under heavy load, clients might end their
-                // session while the scene is resolving
-                if (!source.isActive()) {
-                    Log.info("Abandoning scene move, client gone [who=" + source.who()  +
-                             ", dest=" + scmgr.where() + "].");
-                    InvocationMarshaller.setNoResponse(listener);
-                    return;
-                }
-                finishMoveToRequest(source, scmgr, sceneVer, listener);
-            }
-
-            public void sceneFailedToResolve (int rsceneId, Exception reason) {
-                Log.warning("Unable to resolve scene [sceneid=" + rsceneId +
-                            ", reason=" + reason + "].");
-                // pretend like the scene doesn't exist to the client
-                listener.requestFailed(NO_SUCH_PLACE);
-            }
-        };
-
-        // make sure the scene they are headed to is actually loaded into the server
-        resolveScene(sceneId, rl);
-    }
-
-    /**
-     * Moves the supplied body into the supplied (already resolved) scene and informs the supplied
-     * listener if the move is successful.
-     *
-     * @exception InvocationException thrown if a failure occurs attempting to move the user into
-     * the place associated with the scene.
-     */
-    public void effectSceneMove (BodyObject source, SceneManager scmgr,
-                                 int sceneVersion, SceneService.SceneMoveListener listener)
-        throws InvocationException
-    {
-        // move to the place object associated with this scene
-        int ploid = scmgr.getPlaceObject().getOid();
-        PlaceConfig config = CrowdServer.plreg.locprov.moveTo(source, ploid);
-
-        // now that we've finally moved, we can update the user object with the new scene id
-        ((ScenedBodyObject)source).setSceneId(scmgr.getScene().getId());
-
-        // check to see if they need a newer version of the scene data
-        SceneModel model = scmgr.getScene().getSceneModel();
-        if (sceneVersion != model.version) {
-            SceneUpdate[] updates = null;
-            if (sceneVersion < model.version) {
-                // try getting updates to bring the client to the right version
-                updates = scmgr.getUpdates(sceneVersion);
-            }
-            if (updates != null) {
-                listener.moveSucceededWithUpdates(ploid, config, updates);
-            } else {
-                listener.moveSucceededWithScene(ploid, config, model);
-            }
-        } else {
-            listener.moveSucceeded(ploid, config);
-        }
     }
 
     /**
@@ -315,25 +254,6 @@ public class SceneRegistry
         source.setSceneId(0);
     }
 
-    /**
-     * This is called after the scene to which we are moving is guaranteed to have been loaded into
-     * the server.
-     */
-    protected void finishMoveToRequest (BodyObject source, SceneManager scmgr, int sceneVersion,
-                                        SceneService.SceneMoveListener listener)
-    {
-        try {
-            effectSceneMove(source, scmgr, sceneVersion, listener);
-
-        } catch (InvocationException sfe) {
-            listener.requestFailed(sfe.getMessage());
-
-        } catch (RuntimeException re) {
-            Log.logStackTrace(re);
-            listener.requestFailed(INTERNAL_ERROR);
-        }
-    }
-
     /**
      * Called when the scene resolution has completed successfully.
      */

src/java/com/threerings/whirled/spot/server/SpotProvider.java

@@ -83,89 +83,37 @@ public class SpotProvider
             return;
         }
 
-        // avoid cluttering up the method declaration with final keywords
-        final BodyObject fsource = (BodyObject)caller;
-        final int fportalId = portalId;
-        final int fsceneVer = destSceneVer;
-        final SceneMoveListener flistener = listener;
-
         // obtain the source scene
-        final SpotSceneManager srcmgr = (SpotSceneManager)_screg.getSceneManager(sceneId);
+        BodyObject body = (BodyObject)caller;
+        SpotSceneManager srcmgr = (SpotSceneManager)_screg.getSceneManager(sceneId);
         if (srcmgr == null) {
             Log.warning("Traverse portal missing source scene " +
-                        "[user=" + fsource.who() + ", sceneId=" + sceneId +
+                        "[user=" + body.who() + ", sceneId=" + sceneId +
                         ", portalId=" + portalId + "].");
             throw new InvocationException(INTERNAL_ERROR);
         }
 
         // obtain the destination scene and location id
         SpotScene rss = (SpotScene)srcmgr.getScene();
-        final Portal fdest = rss.getPortal(portalId);
+        Portal dest = rss.getPortal(portalId);
 
         // give the source scene manager a chance to do access control
-        String errmsg = srcmgr.mayTraversePortal(fsource, fdest);
+        String errmsg = srcmgr.mayTraversePortal(body, dest);
         if (errmsg != null) {
             throw new InvocationException(errmsg);
         }
 
         // make sure this portal has valid info
-        if (fdest == null || !fdest.isValid()) {
+        if (dest == null || !dest.isValid()) {
-            Log.warning("Traverse portal with invalid portal [user=" + fsource.who() +
+            Log.warning("Traverse portal with invalid portal [user=" + body.who() +
-                        ", scene=" + srcmgr.where() + ", pid=" + portalId + ", portal=" + fdest +
+                        ", scene=" + srcmgr.where() + ", pid=" + portalId + ", portal=" + dest +
                         ", portals=" + StringUtil.toString(rss.getPortals()) + "].");
             throw new InvocationException(NO_SUCH_PORTAL);
         }
 
         // resolve their destination scene
-        SceneRegistry.ResolutionListener rl = new SceneRegistry.ResolutionListener() {
+        _screg.resolveScene(dest.targetSceneId, new SpotSceneMoveHandler(
-            public void sceneWasResolved (SceneManager scmgr) {
+                                srcmgr, body, sceneId, destSceneVer, dest, listener));
-                // make sure our caller is still around; under heavy load, clients might end their
-                // session while the scene is resolving
-                if (!fsource.isActive()) {
-                    Log.info("Abandoning portal traversal, client gone [who=" + fsource.who()  +
-                             ", dest=" + scmgr.where() + "].");
-                    InvocationMarshaller.setNoResponse(flistener);
-                    return;
-                }
-
-                // let the source manager know that this guy is departing via the specified portal
-                srcmgr.willTraversePortal(fsource, fdest);
-
-                SpotSceneManager sscmgr = (SpotSceneManager)scmgr;
-                finishTraversePortalRequest(fsource, sscmgr, fsceneVer, fdest, flistener);
-            }
-
-            public void sceneFailedToResolve (
-                int rsceneId, Exception reason) {
-                Log.warning("Unable to resolve target scene [sceneId=" + rsceneId +
-                            ", reason=" + reason + "].");
-                // pretend like the scene doesn't exist to the client
-                flistener.requestFailed(NO_SUCH_PLACE);
-            }
-        };
-        _screg.resolveScene(fdest.targetSceneId, rl);
-    }
-
-    /**
-     * This is called after the scene to which we are moving is guaranteed to have been loaded into
-     * the server.
-     */
-    protected void finishTraversePortalRequest (
-        BodyObject source, SpotSceneManager destmgr, int sceneVer, Portal dest,
-        SceneMoveListener listener)
-    {
-        // let the destination scene manager know that we're coming in
-        destmgr.mapEnteringBody(source, dest);
-
-        try {
-            // move to the place object associated with this scene
-            _screg.effectSceneMove(source, destmgr, sceneVer, listener);
-        } catch (InvocationException sfe) {
-            listener.requestFailed(sfe.getMessage());
-            // and let the destination scene manager know that we're no
-            // longer coming in
-            destmgr.clearEnteringBody(source);
-        }
     }
 
     /**

src/java/com/threerings/whirled/spot/server/SpotSceneMoveHandler.java

@@ -0,0 +1,69 @@
+//
+// $Id$
+//
+// Vilya library - tools for developing networked games
+// Copyright (C) 2002-2007 Three Rings Design, Inc., All Rights Reserved
+// http://www.threerings.net/code/vilya/
+//
+// This library is free software; you can redistribute it and/or modify it
+// under the terms of the GNU Lesser General Public License as published
+// by the Free Software Foundation; either version 2.1 of the License, or
+// (at your option) any later version.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+// Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public
+// License along with this library; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+
+package com.threerings.whirled.spot.server;
+
+import com.threerings.presents.server.InvocationException;
+
+import com.threerings.crowd.data.BodyObject;
+
+import com.threerings.whirled.client.SceneService;
+import com.threerings.whirled.server.SceneManager;
+import com.threerings.whirled.server.SceneMoveHandler;
+
+import com.threerings.whirled.spot.data.Portal;
+
+/**
+ * Moves a player between scenes, accounting for their exit and entry via portals.
+ */
+public class SpotSceneMoveHandler extends SceneMoveHandler
+{
+    public SpotSceneMoveHandler (SpotSceneManager srcmgr, BodyObject body, int sceneId,
+                                 int sceneVer, Portal dest, SceneService.SceneMoveListener listener)
+    {
+        super(body, sceneId, sceneVer, listener);
+        _srcmgr = srcmgr;
+        _dest = dest;
+    }
+
+    @Override // from AbstractSceneMoveHandler
+    protected void effectSceneMove (SceneManager scmgr)
+        throws InvocationException
+    {
+        // let the source manager know that this guy is departing via the specified portal
+        _srcmgr.willTraversePortal(_body, _dest);
+
+        // let the destination scene manager know that we're coming in
+        SpotSceneManager destmgr = (SpotSceneManager)scmgr;
+        destmgr.mapEnteringBody(_body, _dest);
+
+        try {
+            super.effectSceneMove(destmgr);
+        } catch (InvocationException ie) {
+            // if anything goes haywire, clear out our entering status
+            destmgr.clearEnteringBody(_body);
+            throw ie;
+        }
+    }
+
+    protected SpotSceneManager _srcmgr;
+    protected Portal _dest;
+}

src/java/com/threerings/whirled/zone/client/ZoneService.java

@@ -31,37 +31,30 @@ import com.threerings.whirled.data.SceneUpdate;
 import com.threerings.whirled.zone.data.ZoneSummary;
 
 /**
- * Defines the client interface to the zone related invocation services
+ * The client interface for zone related invocation services (e.g. moving between zones).
- * (e.g. moving between zones).
  */
 public interface ZoneService extends InvocationService
 {
     /** Used to deliver responses to {@link #moveTo} requests. */
     public static interface ZoneMoveListener extends InvocationListener
     {
-        public void moveSucceeded (
+        public void moveSucceeded (int placeId, PlaceConfig config, ZoneSummary summary);
-            int placeId, PlaceConfig config, ZoneSummary summary);
 
         public void moveSucceededWithUpdates (
-            int placeId, PlaceConfig config, ZoneSummary summary,
+            int placeId, PlaceConfig config, ZoneSummary summary, SceneUpdate[] updates);
-            SceneUpdate[] updates);
 
         public void moveSucceededWithScene (
-            int placeId, PlaceConfig config, ZoneSummary summary,
+            int placeId, PlaceConfig config, ZoneSummary summary, SceneModel model);
-            SceneModel model);
     }
 
     /**
-     * Requests that that this client's body be moved to the specified
+     * Requests that that this client's body be moved to the specified scene in the specified zone.
-     * scene in the specified zone.
      *
      * @param zoneId the zone id to which we want to move.
      * @param sceneId the scene id to which we want to move.
-     * @param version the version number of the scene object that we have
+     * @param version the version number of the scene object that we have in our local repository.
-     * in our local repository.
+     * @param listener receives the callback when the request succeeds or fails.
-     * @param listener the object that will receive the callback when the
-     * request succeeds or fails.
      */
-    public void moveTo (Client client, int zoneId, int sceneId,
+    public void moveTo (Client client, int zoneId, int sceneId, int version,
-                        int version, ZoneMoveListener listener);
+                        ZoneMoveListener listener);
 }

src/java/com/threerings/whirled/zone/server/ZoneMoveHandler.java

@@ -0,0 +1,117 @@
+//
+// $Id$
+//
+// Vilya library - tools for developing networked games
+// Copyright (C) 2002-2007 Three Rings Design, Inc., All Rights Reserved
+// http://www.threerings.net/code/vilya/
+//
+// This library is free software; you can redistribute it and/or modify it
+// under the terms of the GNU Lesser General Public License as published
+// by the Free Software Foundation; either version 2.1 of the License, or
+// (at your option) any later version.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+// Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public
+// License along with this library; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+
+package com.threerings.whirled.zone.server;
+
+import com.threerings.presents.server.InvocationException;
+
+import com.threerings.crowd.data.BodyObject;
+import com.threerings.crowd.data.PlaceConfig;
+
+import com.threerings.whirled.client.SceneService;
+import com.threerings.whirled.data.SceneModel;
+import com.threerings.whirled.data.SceneUpdate;
+import com.threerings.whirled.data.ScenedBodyObject;
+import com.threerings.whirled.server.AbstractSceneMoveHandler;
+import com.threerings.whirled.server.SceneManager;
+import com.threerings.whirled.server.SceneMoveHandler;
+import com.threerings.whirled.server.SceneRegistry;
+import com.threerings.whirled.server.WhirledServer;
+
+import com.threerings.whirled.zone.Log;
+import com.threerings.whirled.zone.client.ZoneService;
+import com.threerings.whirled.zone.data.ZoneCodes;
+import com.threerings.whirled.zone.data.ZoneSummary;
+import com.threerings.whirled.zone.data.ZonedBodyObject;
+
+/**
+ * Handles transitioning between zones.
+ */
+public class ZoneMoveHandler extends AbstractSceneMoveHandler
+    implements ZoneManager.ResolutionListener
+{
+    public ZoneMoveHandler (ZoneManager zmgr, BodyObject body, int sceneId, int sceneVer,
+                            ZoneService.ZoneMoveListener listener)
+    {
+        super(body, sceneId, sceneVer, listener);
+        _zmgr = zmgr;
+    }
+
+    // from interface ZoneManager.ResolutionListener
+    public void zoneWasResolved (ZoneSummary summary)
+    {
+        // give the zone manager a chance to veto the request
+        String errmsg = _zmgr.ratifyBodyEntry(_body, summary.zoneId);
+        if (errmsg != null) {
+            _listener.requestFailed(errmsg);
+            return;
+        }
+        _summary = summary;
+
+        // now resolve the target scene
+        WhirledServer.screg.resolveScene(_sceneId, this);
+    }
+
+    // from interface ZoneManager.ResolutionListener
+    public void zoneFailedToResolve (int zoneId, Exception reason)
+    {
+        Log.warning("Unable to resolve zone [zoneId=" + zoneId + ", reason=" + reason + "].");
+        _listener.requestFailed(ZoneCodes.NO_SUCH_ZONE);
+    }
+
+    @Override // from AbstractSceneMoveHandler
+    protected void effectSceneMove (SceneManager scmgr)
+        throws InvocationException
+    {
+        // move to the place object associated with this scene
+        int ploid = scmgr.getPlaceObject().getOid();
+        PlaceConfig config = WhirledServer.plreg.locprov.moveTo(_body, ploid);
+
+        // now that we've moved, we can update the user object with the new scene and zone ids
+        _body.startTransaction();
+        try {
+            ((ScenedBodyObject)_body).setSceneId(scmgr.getScene().getId());
+            ((ZonedBodyObject)_body).setZoneId(_summary.zoneId);
+        } finally {
+            _body.commitTransaction();
+        }
+
+        // check to see if they need a newer version of the scene data
+        ZoneService.ZoneMoveListener listener = (ZoneService.ZoneMoveListener)_listener;
+        SceneModel model = scmgr.getScene().getSceneModel();
+        if (_version < model.version) {
+            SceneUpdate[] updates = scmgr.getUpdates(_version);
+            if (updates != null) {
+                listener.moveSucceededWithUpdates(ploid, config, _summary, updates);
+            } else {
+                listener.moveSucceededWithScene(ploid, config, _summary, model);
+            }
+        } else {
+            listener.moveSucceeded(ploid, config, _summary);
+        }
+
+        // let the zone manager know that someone just came on in
+        _zmgr.bodyDidEnterZone(_body, _summary.zoneId);
+    }
+
+    protected ZoneManager _zmgr;
+    protected ZoneSummary _summary;
+}

src/java/com/threerings/whirled/zone/server/ZoneProvider.java

@@ -44,20 +44,17 @@ import com.threerings.whirled.zone.data.ZoneSummary;
 import com.threerings.whirled.zone.data.ZonedBodyObject;
 
 /**
- * Provides zone related services which are presently the ability to move
+ * Provides zone related services which are presently the ability to move from zone to zone.
- * from zone to zone.
  */
 public class ZoneProvider
     implements ZoneCodes, InvocationProvider
 {
     /**
-     * Constructs a zone provider that will interoperate with the supplied
+     * Constructs a zone provider that will interoperate with the supplied zone and scene
-     * zone and scene registries. The zone provider will automatically be
+     * registries. The zone provider will automatically be constructed and registered by the {@link
-     * constructed and registered by the {@link ZoneRegistry}, which a
+     * ZoneRegistry}, which a zone-using system must create and initialize in their server.
-     * zone-using system must create and initialize in their server.
      */
-    public ZoneProvider (LocationProvider locprov, ZoneRegistry zonereg,
+    public ZoneProvider (LocationProvider locprov, ZoneRegistry zonereg, SceneRegistry screg)
-                         SceneRegistry screg)
     {
         _locprov = locprov;
         _zonereg = zonereg;
@@ -70,31 +67,25 @@ public class ZoneProvider
      * @param caller the user requesting the move.
      * @param zoneId the qualified zone id of the new zone.
      * @param sceneId the identifier of the new scene.
-     * @param sceneVer the version of the scene model currently held by
+     * @param sceneVer the version of the scene model currently held by the client.
-     * the client.
      * @param listener the entity to inform of success or failure.
      */
     public void moveTo (ClientObject caller, int zoneId, int sceneId,
                         int sceneVer, ZoneMoveListener listener)
         throws InvocationException
     {
-        // avoid cluttering up the method declaration with final keywords
-        final BodyObject fsource = (BodyObject)caller;
-        final int fsceneId = sceneId;
-        final int fsceneVer = sceneVer;
-        final ZoneMoveListener flistener = listener;
-
-        // look up the caller's current zone id and make sure it is happy
-        // about their departure from the current zone
         if (!(caller instanceof ZonedBodyObject)) {
-            Log.warning("Request to switch zones by non-ZonedBodyObject!? " +
+            Log.warning("Request to switch zones by non-ZonedBodyObject " +
                         "[clobj=" + caller.getClass() + "].");
             throw new InvocationException(INTERNAL_ERROR);
         }
-        ZonedBodyObject zcaller = (ZonedBodyObject)caller;
+
-        ZoneManager ozmgr = _zonereg.getZoneManager(zcaller.getZoneId());
+        // look up the caller's current zone id and make sure it is happy about their departure
+        // from the current zone
+        BodyObject body = (BodyObject)caller;
+        ZoneManager ozmgr = _zonereg.getZoneManager(((ZonedBodyObject)caller).getZoneId());
         if (ozmgr != null) {
-            String msg = ozmgr.ratifyBodyExit(fsource);
+            String msg = ozmgr.ratifyBodyExit(body);
             if (msg != null) {
                 throw new InvocationException(msg);
             }
@@ -103,146 +94,23 @@ public class ZoneProvider
         // look up the zone manager for the zone
         ZoneManager zmgr = _zonereg.getZoneManager(zoneId);
         if (zmgr == null) {
-            Log.warning("Requested to enter a zone for which we have no " +
+            Log.warning("Requested to enter a zone for which we have no manager " +
-                        "manager [user=" + fsource.who() +
+                        "[user=" + body.who() + ", zoneId=" + zoneId + "].");
-                        ", zoneId=" + zoneId + "].");
             throw new InvocationException(NO_SUCH_ZONE);
         }
 
-        // resolve the zone!
+        // resolve the zone and move the user
-        ZoneManager.ResolutionListener zl = new ZoneManager.ResolutionListener()
+        zmgr.resolveZone(zoneId, new ZoneMoveHandler(
-        {
+                             zmgr, (BodyObject)caller, sceneId, sceneVer, listener));
-            public void zoneWasResolved (ZoneSummary summary) {
-                continueMoveTo(
-                    fsource, summary, fsceneId, fsceneVer, flistener);
-            }
-
-            public void zoneFailedToResolve (int zoneId, Exception reason) {
-                Log.warning("Unable to resolve zone [zoneId=" + zoneId +
-                            ", reason=" + reason + "].");
-                flistener.requestFailed(NO_SUCH_ZONE);
-            }
-        };
-        zmgr.resolveZone(zoneId, zl);
     }
 
     /**
-     * This is called after we have resolved our zone.
+     * Ejects the specified body from their current scene and sends them a request to move to the
-     */
+     * specified new zone and scene. This is the zone-equivalent to {@link
-    protected void continueMoveTo (
+     * LocationProvider#moveBody}.
-        BodyObject source, ZoneSummary summary, int sceneId, int sceneVer,
-        ZoneMoveListener listener)
-    {
-        // avoid cluttering up the method declaration with final keywords
-        final BodyObject fsource = source;
-        final ZoneSummary fsum = summary;
-        final int fsceneVer = sceneVer;
-        final ZoneMoveListener flistener = listener;
-
-        // give the zone manager a chance to veto the request
-        ZoneManager zmgr = _zonereg.getZoneManager(summary.zoneId);
-        String errmsg = zmgr.ratifyBodyEntry(source, summary.zoneId);
-        if (errmsg != null) {
-            listener.requestFailed(errmsg);
-            return;
-        }
-
-        // create a callback object that will handle the resolution or
-        // failed resolution of the scene
-        SceneRegistry.ResolutionListener rl = null;
-        rl = new SceneRegistry.ResolutionListener() {
-            public void sceneWasResolved (SceneManager scmgr) {
-                // make sure our caller is still around; under heavy load,
-                // clients might end their session while the scene is
-                // resolving
-                if (!fsource.isActive()) {
-                    Log.info("Abandoning zone move, client gone " +
-                             "[who=" + fsource.who()  +
-                             ", dest=" + scmgr.where() + "].");
-                    // No one to respond to, just mark that we're okay with it.
-                    InvocationMarshaller.setNoResponse(flistener);
-                    return;
-                }
-                finishMoveTo(fsource, fsum, scmgr, fsceneVer, flistener);
-            }
-
-            public void sceneFailedToResolve (int sceneId, Exception reason) {
-                Log.warning("Unable to resolve scene [sceneid=" + sceneId +
-                            ", reason=" + reason + "].");
-                // pretend like the scene doesn't exist to the client
-                flistener.requestFailed(NO_SUCH_PLACE);
-            }
-        };
-
-        // make sure the scene they are headed to is actually loaded into
-        // the server
-        _screg.resolveScene(sceneId, rl);
-    }
-
-    /**
-     * This is called after the scene to which we are moving is guaranteed
-     * to have been loaded into the server.
-     */
-    protected void finishMoveTo (
-        BodyObject source, ZoneSummary summary, SceneManager scmgr,
-        int sceneVersion, ZoneMoveListener listener)
-    {
-        // move to the place object associated with this scene
-        PlaceObject plobj = scmgr.getPlaceObject();
-        int ploid = plobj.getOid();
-
-        try {
-            // try doing the actual move
-            PlaceConfig config = _locprov.moveTo(source, ploid);
-
-            // now that we've finally moved, we can update the user object
-            // with the new scene and zone ids
-            source.startTransaction();
-            try {
-                ((ScenedBodyObject)source).setSceneId(scmgr.getScene().getId());
-                ((ZonedBodyObject)source).setZoneId(summary.zoneId);
-            } finally {
-                source.commitTransaction();
-            }
-
-            // check to see if they need a newer version of the scene data
-            SceneModel model = scmgr.getScene().getSceneModel();
-            if (sceneVersion < model.version) {
-                SceneUpdate[] updates = scmgr.getUpdates(sceneVersion);
-                if (updates != null) {
-                    listener.moveSucceededWithUpdates(
-                        ploid, config, summary, updates);
-                } else {
-                    listener.moveSucceededWithScene(
-                        ploid, config, summary, model);
-                }
-
-            } else {
-                // then send the moveTo response
-                listener.moveSucceeded(ploid, config, summary);
-            }
-
-            // let the zone manager know that someone just came on in
-            ZoneManager zmgr = _zonereg.getZoneManager(summary.zoneId);
-            zmgr.bodyDidEnterZone(source, summary.zoneId);
-
-        } catch (InvocationException ie) {
-            listener.requestFailed(ie.getMessage());
-
-        } catch (RuntimeException re) {
-            Log.logStackTrace(re);
-            listener.requestFailed(INTERNAL_ERROR);
-        }
-    }
-
-    /**
-     * Ejects the specified body from their current scene and sends them a
-     * request to move to the specified new zone and scene. This is the
-     * zone-equivalent to {@link LocationProvider#moveBody}.
      *
-     * @return null if the user was forcibly moved, or a string indicating
+     * @return null if the user was forcibly moved, or a string indicating the reason for denial of
-     * the reason for denial of departure of their current zone (from
+     * departure of their current zone (from {@link ZoneManager#ratifyBodyExit}).
-     * {@link ZoneManager#ratifyBodyExit}).
      */
     public String moveBody (ZonedBodyObject source, int zoneId, int sceneId)
     {
@@ -264,18 +132,16 @@ public class ZoneProvider
     }
 
     /**
-     * Ejects the specified body from their current scene and zone. This
+     * Ejects the specified body from their current scene and zone. This is the zone equivalent to
-     * is the zone equivalent to {@link
+     * {@link LocationProvider#leaveOccupiedPlace}.
-     * LocationProvider#leaveOccupiedPlace}.
      *
-     * @return null if the user was forcibly moved, or a string indicating
+     * @return null if the user was forcibly moved, or a string indicating the reason for denial of
-     * the reason for denial of departure of their current zone (from
+     * departure of their current zone (from {@link ZoneManager#ratifyBodyExit}).
-     * {@link ZoneManager#ratifyBodyExit}).
      */
     public String leaveOccupiedZone (ZonedBodyObject source)
     {
-        // look up the caller's current zone id and make sure it is happy
+        // look up the caller's current zone id and make sure it is happy about their departure
-        // about their departure from the current zone
+        // from the current zone
         ZoneManager zmgr = _zonereg.getZoneManager(source.getZoneId());
         String msg;
         if (zmgr != null &&