[444261] Reloads the resources when changes are canceled.

* Instead of undoing changes to retrieve the state before the user
modified the resource, we now reload resources.
* Creates a new resource status to handle this case.
* Removes the RestoreToLastSavePointListener which is not necessary
anymore.

Bug: 444261
Change-Id: Id814706367282b1da53ff8497b1c7d406d2c69d6
Signed-off-by: Florian Barbin <florian.barbin@obeo.fr>

9 files changed, 152 insertions, 183 deletions

diff --git a/plugins/org.eclipse.sirius.common/src/org/eclipse/sirius/common/tools/api/resource/ResourceSetSync.java b/plugins/org.eclipse.sirius.common/src/org/eclipse/sirius/common/tools/api/resource/ResourceSetSync.java
index 9ebb8945cf..8740f26443 100644
--- a/plugins/org.eclipse.sirius.common/src/org/eclipse/sirius/common/tools/api/resource/ResourceSetSync.java
+++ b/plugins/org.eclipse.sirius.common/src/org/eclipse/sirius/common/tools/api/resource/ResourceSetSync.java
@@ -97,7 +97,7 @@ public final class ResourceSetSync extends ResourceSetListenerImpl implements Re
         /**
          * The resource in-memory status in regard of the physical data.
          */
-        CHANGED, EXTERNAL_CHANGED, CONFLICTING_CHANGED, CONFLICTING_DELETED, DELETED, SYNC, UNKNOWN
+        CHANGED, EXTERNAL_CHANGED, CONFLICTING_CHANGED, CONFLICTING_DELETED, DELETED, SYNC, CHANGES_CANCELED, UNKNOWN
     }
 
     /**
diff --git a/plugins/org.eclipse.sirius.doc/doc/Release Notes.html b/plugins/org.eclipse.sirius.doc/doc/Release Notes.html
index a809e5820e..1fb5d13cea 100644
--- a/plugins/org.eclipse.sirius.doc/doc/Release Notes.html
+++ b/plugins/org.eclipse.sirius.doc/doc/Release Notes.html
@@ -105,6 +105,10 @@
 			<li>The static method 
 				<code>org.eclipse.sirius.common.tools.api.util.ReflectionHelper.getFieldValueWithoutException(Class&lt;?&gt;, String)</code> has been added to return an internal static value of a class.   
 			</li>
+			<li>
+				<code>org.eclipse.sirius.common.tools.api.resource.ResourceSetSync</code> has a new state 
+				<code>CHANGES_CANCELED</code> used to define the state where the user canceled its changes.
+			</li>
 		</ul>
 		<h4 id="Changesinorg.eclipse.sirius.ecore.extender">Changes in 
 			<code>org.eclipse.sirius.ecore.extender</code>
@@ -2188,4 +2192,4 @@ void removeSelectedView(DView view);
 			<li>The ability to print table representations has been disabled for the 0.9 release due to an external dependency issue (see <a href="https://bugs.eclipse.org/bugs/show_bug.cgi?id=422223" target="_blank">bug #422223</a>: for the details). It should be re-introduced in 1.0.</li>
 		</ul>
 	</body>
-</html>
\ No newline at end of file
+</html>
diff --git a/plugins/org.eclipse.sirius.doc/doc/Release Notes.textile b/plugins/org.eclipse.sirius.doc/doc/Release Notes.textile
index c7488cbcba..7e68bf2886 100644
--- a/plugins/org.eclipse.sirius.doc/doc/Release Notes.textile
+++ b/plugins/org.eclipse.sirius.doc/doc/Release Notes.textile
@@ -33,6 +33,7 @@ h4. Changes in @org.eclipse.sirius.common@
 * @org.eclipse.sirius.common.tools.api.util.ECrossReferenceAdapterWithUnproxyCapability@ is a specific kind of ECrossReferenceAdapter. It provides the capability to resolve all proxy cross references to a given resource. It is now used by the Session as semantic cross referencer. This type is exposed as API but it is not intended to be used/referenced/extended by user code (as the below @LazyCrossReferencer@ type).
 * @org.eclipse.sirius.common.tools.api.util.LazyCrossReferencer@ now extends @ECrossReferenceAdapterWithUnproxyCapability@ and implements @resolveProxyCrossReferences(Resource)@.
 * The static method @org.eclipse.sirius.common.tools.api.util.ReflectionHelper.getFieldValueWithoutException(Class<?>, String)@ has been added to return an internal static value of a class.   
+* @org.eclipse.sirius.common.tools.api.resource.ResourceSetSync@ has a new state @CHANGES_CANCELED@ used to define the state where the user canceled its changes.
 
 h4. Changes in @org.eclipse.sirius.ecore.extender@
 
diff --git a/plugins/org.eclipse.sirius.tests.swtbot/src/org/eclipse/sirius/tests/swtbot/CloseWithoutSavingTest.java b/plugins/org.eclipse.sirius.tests.swtbot/src/org/eclipse/sirius/tests/swtbot/CloseWithoutSavingTest.java
new file mode 100644
index 0000000000..8718ccaea9
--- /dev/null
+++ b/plugins/org.eclipse.sirius.tests.swtbot/src/org/eclipse/sirius/tests/swtbot/CloseWithoutSavingTest.java
@@ -0,0 +1,94 @@
+/*******************************************************************************
+ * Copyright (c) 2015 Obeo.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *    Obeo - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.sirius.tests.swtbot;
+
+import org.eclipse.draw2d.geometry.Point;
+import org.eclipse.sirius.diagram.DDiagram;
+import org.eclipse.sirius.tests.swtbot.support.api.AbstractSiriusSwtBotGefTestCase;
+import org.eclipse.sirius.tests.swtbot.support.api.business.UILocalSession;
+import org.eclipse.sirius.tests.swtbot.support.api.business.UIResource;
+import org.eclipse.sirius.tests.swtbot.support.api.condition.ItemEnabledCondition;
+import org.eclipse.sirius.tests.swtbot.support.api.editor.SWTBotSiriusDiagramEditor;
+import org.eclipse.sirius.tests.swtbot.support.api.editor.SWTBotSiriusHelper;
+import org.eclipse.sirius.tests.swtbot.support.utils.SWTBotUtils;
+import org.eclipse.sirius.tests.unit.diagram.modeler.ecore.EcoreModeler;
+import org.eclipse.swtbot.eclipse.finder.waits.Conditions;
+import org.eclipse.swtbot.swt.finder.widgets.SWTBotButton;
+import org.eclipse.swtbot.swt.finder.widgets.SWTBotShell;
+
+/**
+ * Tests that the session modifications are properly canceled when the user
+ * chooses to don't save the changes.
+ * 
+ * @author Florian Barbin
+ */
+public class CloseWithoutSavingTest extends AbstractSiriusSwtBotGefTestCase implements EcoreModeler {
+
+    private static final String MODEL = "blank.ecore";
+
+    private static final String DATA_UNIT_DIR = "data/unit/blankEcore/";
+
+    private UILocalSession localSession;
+
+    private DDiagram diagram;
+
+    @Override
+    protected void onSetUpBeforeClosingWelcomePage() throws Exception {
+        copyFileToTestProject(Activator.PLUGIN_ID, DATA_UNIT_DIR, MODEL);
+    }
+
+    @Override
+    protected void onSetUpAfterOpeningDesignerPerspective() throws Exception {
+        UIResource semanticModel = new UIResource(designerProject, "/", MODEL);
+        localSession = designerPerspective.openSessionCreationWizardFromSemanticResource(semanticModel).fromAlreadySelectedSemanticResource().withDefaultSessionName().finish()
+                .selectViewpoints(DESIGN_VIEWPOINT_NAME);
+        editor = (SWTBotSiriusDiagramEditor) openRepresentation(localSession.getOpenedSession(), ENTITIES_DESC_NAME, "root" + " package entities", DDiagram.class);
+        editor.save();
+        diagram = (DDiagram) getRepresentationWithName(localSession.getOpenedSession(), ENTITIES_DESC_NAME, "root" + " package entities");
+    }
+
+    /**
+     * This test creates multiple EPackages and make sure the restore to the
+     * last save point works properly.
+     */
+    public void testCreateMultipleElementsAndCloseWithoutSaving() {
+        assertEquals("The diagram should be empty", 0, diagram.getOwnedDiagramElements().size());
+        for (int i = 0; i < 35; i++) {
+            editor.activateTool("Package");
+            editor.click(new Point(2, 2));
+            SWTBotUtils.waitAllUiEvents();
+        }
+
+        // Closes the editor without saving.
+        SWTBotSiriusHelper.close(editor, true);
+        bot.waitUntilWidgetAppears(Conditions.shellIsActive("Save"));
+        final SWTBotShell uncontrolShell = bot.shell("Save");
+        uncontrolShell.activate();
+        SWTBotButton no = bot.button("No");
+        bot.waitUntilWidgetAppears(new ItemEnabledCondition(no));
+        no.click();
+
+        SWTBotUtils.waitAllUiEvents();
+
+        // Retrieves the diagram and makes sure it's empty.
+        diagram = (DDiagram) getRepresentationWithName(localSession.getOpenedSession(), ENTITIES_DESC_NAME, "root" + " package entities");
+        assertEquals("The diagram should be empty after having closed without saving.", 0, diagram.getDiagramElements().size());
+    }
+
+    @Override
+    protected void tearDown() throws Exception {
+        localSession = null;
+        diagram = null;
+        editor = null;
+        super.tearDown();
+    }
+
+}
diff --git a/plugins/org.eclipse.sirius.tests.swtbot/src/org/eclipse/sirius/tests/swtbot/suite/AllTestSuite.java b/plugins/org.eclipse.sirius.tests.swtbot/src/org/eclipse/sirius/tests/swtbot/suite/AllTestSuite.java
index 4244b23f40..7c7e164182 100644
--- a/plugins/org.eclipse.sirius.tests.swtbot/src/org/eclipse/sirius/tests/swtbot/suite/AllTestSuite.java
+++ b/plugins/org.eclipse.sirius.tests.swtbot/src/org/eclipse/sirius/tests/swtbot/suite/AllTestSuite.java
@@ -170,6 +170,7 @@ public class AllTestSuite extends TestCase {
         suite.addTestSuite(NodeCreationWithSnapToGridTest.class);
         suite.addTestSuite(GenericClipboardSupportTest.class);
         suite.addTestSuite(MultiSessionCopyPasteTest.class);
+        suite.addTestSuite(CloseWithoutSavingTest.class);
     }
 
     /**
diff --git a/plugins/org.eclipse.sirius.ui/src/org/eclipse/sirius/ui/business/internal/session/EditingSession.java b/plugins/org.eclipse.sirius.ui/src/org/eclipse/sirius/ui/business/internal/session/EditingSession.java
index 38fc72e9ef..6a624fd06f 100644
--- a/plugins/org.eclipse.sirius.ui/src/org/eclipse/sirius/ui/business/internal/session/EditingSession.java
+++ b/plugins/org.eclipse.sirius.ui/src/org/eclipse/sirius/ui/business/internal/session/EditingSession.java
@@ -28,12 +28,16 @@ import org.eclipse.jface.preference.IPreferenceStore;
 import org.eclipse.sirius.business.api.session.Session;
 import org.eclipse.sirius.business.api.session.danalysis.DAnalysisSession;
 import org.eclipse.sirius.business.internal.session.ReloadingPolicyImpl;
+import org.eclipse.sirius.common.tools.api.resource.ResourceSetSync.ResourceStatus;
+import org.eclipse.sirius.common.tools.api.resource.ResourceSyncClient;
+import org.eclipse.sirius.common.tools.api.resource.ResourceSyncClient.ResourceStatusChange;
 import org.eclipse.sirius.common.ui.tools.api.util.EclipseUIUtil;
 import org.eclipse.sirius.common.ui.tools.api.util.SWTUtil;
 import org.eclipse.sirius.tools.api.command.ui.RefreshFilter;
 import org.eclipse.sirius.tools.api.command.ui.RefreshFilterManager;
 import org.eclipse.sirius.ui.business.api.dialect.DialectEditor;
 import org.eclipse.sirius.ui.business.api.dialect.DialectUIManager;
+import org.eclipse.sirius.ui.business.api.preferences.SiriusUIPreferencesKeys;
 import org.eclipse.sirius.ui.business.api.session.EditingSessionEvent;
 import org.eclipse.sirius.ui.business.api.session.EditorNameAdapter;
 import org.eclipse.sirius.ui.business.api.session.IEditingSession;
@@ -86,8 +90,6 @@ public class EditingSession implements IEditingSession, ISaveablesSource, Refres
      */
     private EditorNameAdapter editorNameAdapter;
 
-    private RestoreToLastSavePointListener restoreToSavePointListener;
-
     private SaveSessionWhenNoDialectEditorsListener saveSessionListener;
 
     /**
@@ -104,18 +106,11 @@ public class EditingSession implements IEditingSession, ISaveablesSource, Refres
     }
 
     private void initListeners() {
-        this.restoreToSavePointListener = new RestoreToLastSavePointListener(session);
-        this.restoreToSavePointListener.register();
         this.saveSessionListener = new SaveSessionWhenNoDialectEditorsListener(session);
         this.saveSessionListener.register();
     }
 
     private void removeListeners() {
-        if (restoreToSavePointListener != null) {
-            restoreToSavePointListener.unregister();
-            restoreToSavePointListener.dispose();
-            restoreToSavePointListener = null;
-        }
 
         if (this.saveSessionListener != null) {
             this.saveSessionListener.unregister();
@@ -239,21 +234,53 @@ public class EditingSession implements IEditingSession, ISaveablesSource, Refres
         int choice = ISaveablePart2.DEFAULT;
         if (saveable != null) {
             boolean stillOpenElsewhere = getEditors().size() > 1 && !closeAllDetected();
-            boolean promptStandardDialog = !RestoreToLastSavePointListener.isAllowedToReturnToSyncState();
+            boolean promptStandardDialog = !isAllowedToReturnToSyncState();
 
             choice = SWTUtil.showSaveDialog(session, saveable.getName(), true, stillOpenElsewhere, promptStandardDialog);
 
             if (choice == ISaveablePart2.CANCEL) {
                 needSaveOnCloseDetec.reInit();
             } else if (choice == ISaveablePart2.NO && (getEditors().size() == 1 || closeAllDetected())) {
-                if (restoreToSavePointListener != null) {
-                    restoreToSavePointListener.returnToSyncState();
-                }
+                returnToSyncState();
             }
         }
         return choice;
     }
 
+    /**
+     * Notifies the session that the changes have been canceled by user. That
+     * will cause the reloading of "changed" resources.
+     */
+    private void returnToSyncState() {
+        if (isAllowedToReturnToSyncState()) {
+            List<ResourceStatusChange> changes = new ArrayList<ResourceStatusChange>();
+            for (Resource currentResource : session.getAllSessionResources()) {
+                if (currentResource.isModified()) {
+                    changes.add(new ResourceStatusChange(currentResource, ResourceStatus.CHANGES_CANCELED, ResourceStatus.CHANGED));
+                }
+            }
+            for (Resource currentResource : session.getSemanticResources()) {
+                if (currentResource.isModified()) {
+                    changes.add(new ResourceStatusChange(currentResource, ResourceStatus.CHANGES_CANCELED, ResourceStatus.CHANGED));
+                }
+            }
+            if (session instanceof ResourceSyncClient) {
+                ((ResourceSyncClient) session).statusesChanged(changes);
+            }
+        }
+    }
+
+    /**
+     * Check the DesignerUIPreferencesKeys.PREF_RELOAD_ON_LAST_EDITOR_CLOSE
+     * preference state.
+     * 
+     * @return the preference value.
+     */
+    private boolean isAllowedToReturnToSyncState() {
+        IPreferenceStore preferenceStore = SiriusEditPlugin.getPlugin().getPreferenceStore();
+        return preferenceStore != null && preferenceStore.getBoolean(SiriusUIPreferencesKeys.PREF_RELOAD_ON_LAST_EDITOR_CLOSE.name());
+    }
+
     private boolean closeAllDetected() {
         return needSaveOnCloseDetec.closeAllDetected();
     }
diff --git a/plugins/org.eclipse.sirius.ui/src/org/eclipse/sirius/ui/business/internal/session/RestoreToLastSavePointListener.java b/plugins/org.eclipse.sirius.ui/src/org/eclipse/sirius/ui/business/internal/session/RestoreToLastSavePointListener.java
deleted file mode 100644
index 89d25b9c5f..0000000000
--- a/plugins/org.eclipse.sirius.ui/src/org/eclipse/sirius/ui/business/internal/session/RestoreToLastSavePointListener.java
+++ /dev/null
@@ -1,167 +0,0 @@
-/*******************************************************************************
- * Copyright (c) 2011, 2014 THALES GLOBAL SERVICES and others.
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the Eclipse Public License v1.0
- * which accompanies this distribution, and is available at
- * http://www.eclipse.org/legal/epl-v10.html
- *
- * Contributors:
- *    Obeo - initial API and implementation
- *******************************************************************************/
-package org.eclipse.sirius.ui.business.internal.session;
-
-import java.util.Collection;
-
-import org.eclipse.core.commands.ExecutionException;
-import org.eclipse.core.commands.operations.IOperationHistory;
-import org.eclipse.core.commands.operations.IOperationHistoryListener;
-import org.eclipse.core.commands.operations.IUndoContext;
-import org.eclipse.core.commands.operations.IUndoableOperation;
-import org.eclipse.core.commands.operations.ObjectUndoContext;
-import org.eclipse.core.commands.operations.OperationHistoryEvent;
-import org.eclipse.core.commands.operations.OperationHistoryFactory;
-import org.eclipse.core.runtime.IProgressMonitor;
-import org.eclipse.core.runtime.NullProgressMonitor;
-import org.eclipse.emf.ecore.resource.Resource;
-import org.eclipse.emf.workspace.IWorkspaceCommandStack;
-import org.eclipse.jface.preference.IPreferenceStore;
-import org.eclipse.sirius.business.api.session.Session;
-import org.eclipse.sirius.business.api.session.SessionStatus;
-import org.eclipse.sirius.common.tools.api.resource.ResourceSetSync;
-import org.eclipse.sirius.common.tools.api.resource.ResourceSetSync.ResourceStatus;
-import org.eclipse.sirius.common.tools.api.resource.ResourceSyncClient;
-import org.eclipse.sirius.ext.base.Option;
-import org.eclipse.sirius.tools.api.command.EditingDomainUndoContext;
-import org.eclipse.sirius.ui.business.api.preferences.SiriusUIPreferencesKeys;
-import org.eclipse.sirius.viewpoint.SiriusPlugin;
-import org.eclipse.sirius.viewpoint.provider.SiriusEditPlugin;
-
-/**
- * Marker able to restore the command stack to the last save point.
- * 
- * @author mporhel
- */
-public class RestoreToLastSavePointListener implements ResourceSyncClient, IOperationHistoryListener {
-
-    private IUndoableOperation marker;
-
-    private Session session;
-
-    /**
-     * Create a new instance.
-     * 
-     * @param session
-     *            the session to listen
-     */
-    public RestoreToLastSavePointListener(Session session) {
-        this.session = session;
-    }
-
-    /**
-     * Register this listener.
-     */
-    public void register() {
-        OperationHistoryFactory.getOperationHistory().addOperationHistoryListener(this);
-        ResourceSetSync.getOrInstallResourceSetSync(session.getTransactionalEditingDomain()).registerClient(this);
-    }
-
-    /**
-     * Unregister this listener.
-     */
-    public void unregister() {
-        OperationHistoryFactory.getOperationHistory().removeOperationHistoryListener(this);
-        // Do not call ResourceSetSync.getOrInstallResourceSetSync as the
-        // ResourceSetSync could already have been removed.
-        Option<ResourceSetSync> resourceSetSync = ResourceSetSync.getResourceSetSync(session.getTransactionalEditingDomain());
-        if (resourceSetSync.some()) {
-            resourceSetSync.get().unregisterClient(this);
-        }
-    }
-
-    /**
-     * Return to the last save point.
-     */
-    public void returnToSyncState() {
-        if (isAllowedToReturnToSyncState()) {
-            IProgressMonitor pm = new NullProgressMonitor();
-            try {
-                IOperationHistory operationHistory = OperationHistoryFactory.getOperationHistory();
-                IUndoContext undoCtx;
-                if (session.getTransactionalEditingDomain() != null) {
-                    if (session.getTransactionalEditingDomain().getCommandStack() instanceof IWorkspaceCommandStack) {
-                        undoCtx = ((IWorkspaceCommandStack) session.getTransactionalEditingDomain().getCommandStack()).getDefaultUndoContext();
-                    } else {
-                        undoCtx = new EditingDomainUndoContext(session.getTransactionalEditingDomain());
-                    }
-                } else {
-                    undoCtx = new ObjectUndoContext(this);
-                }
-                while (operationHistory != null && operationHistory.canUndo(undoCtx) && session.getStatus() != SessionStatus.SYNC) {
-                    IUndoableOperation toUndo = operationHistory.getUndoOperation(undoCtx);
-
-                    operationHistory.undoOperation(toUndo, new NullProgressMonitor(), null);
-
-                    if (marker == toUndo) {
-                        break;
-                    }
-                }
-                session.save(pm);
-            } catch (ExecutionException e) {
-                // Session could not be reloaded, close it.
-                session.close(pm);
-                String sessionLabel = SiriusEditPlugin.getPlugin().getUiCallback().getSessionNameToDisplayWhileSaving(session);
-                SiriusPlugin.getDefault().warning(sessionLabel + " were closed. An error occurs while attempting to cancel all modifications. No modification were saved.", e);
-            }
-        }
-    }
-
-    /**
-     * Check the DesignerUIPreferencesKeys.PREF_RELOAD_ON_LAST_EDITOR_CLOSE
-     * preference state.
-     * 
-     * @return the preference value.
-     */
-    public static boolean isAllowedToReturnToSyncState() {
-        IPreferenceStore preferenceStore = SiriusEditPlugin.getPlugin().getPreferenceStore();
-        return preferenceStore != null && preferenceStore.getBoolean(SiriusUIPreferencesKeys.PREF_RELOAD_ON_LAST_EDITOR_CLOSE.name());
-    }
-
-    /**
-     * Dispose this listener.
-     */
-    public void dispose() {
-        session = null;
-        marker = null;
-    }
-
-    /**
-     * {@inheritDoc}
-     */
-    public void statusChanged(Resource resource, ResourceStatus oldStatus, ResourceStatus newStatus) {
-        // Do nothing while processing,
-        // see statusesChanged(Collection<ReResourceStatusChange>)
-    }
-
-    /**
-     * {@inheritDoc}
-     */
-    public void statusesChanged(Collection<ResourceStatusChange> changes) {
-        /* this may be call in a async thread */
-        if (session != null) {
-            if (SessionStatus.SYNC.equals(session.getStatus())) {
-                marker = null;
-            }
-        }
-    }
-
-    /**
-     * {@inheritDoc}
-     */
-    public void historyNotification(OperationHistoryEvent event) {
-        if (session != null && SessionStatus.DIRTY.equals(session.getStatus())) {
-            if (marker == null) {
-                marker = event.getOperation();
-            }
-        }
-    }
-}
diff --git a/plugins/org.eclipse.sirius/src/org/eclipse/sirius/business/internal/session/ReloadingPolicyImpl.java b/plugins/org.eclipse.sirius/src/org/eclipse/sirius/business/internal/session/ReloadingPolicyImpl.java
index bf6139b985..95fc4690ec 100644
--- a/plugins/org.eclipse.sirius/src/org/eclipse/sirius/business/internal/session/ReloadingPolicyImpl.java
+++ b/plugins/org.eclipse.sirius/src/org/eclipse/sirius/business/internal/session/ReloadingPolicyImpl.java
@@ -10,6 +10,7 @@
  *******************************************************************************/
 package org.eclipse.sirius.business.internal.session;
 
+import java.util.Arrays;
 import java.util.List;
 
 import org.eclipse.emf.ecore.resource.Resource;
@@ -71,6 +72,9 @@ public class ReloadingPolicyImpl implements ReloadingPolicy {
         case CONFLICTING_DELETED:
             actions = handleExternalDeleteConflict(session, resource, newStatus);
             break;
+        case CHANGES_CANCELED:
+            actions = handleChangesCanceled(session, resource, newStatus);
+            break;
         default:
             break;
         }
@@ -78,6 +82,10 @@ public class ReloadingPolicyImpl implements ReloadingPolicy {
         return actions;
     }
 
+    private List<Action> handleChangesCanceled(Session session, Resource resource, ResourceStatus newStatus) {
+        return Arrays.asList(Action.RELOAD);
+    }
+
     private List<Action> handleExternalChangeConflict(final Session session, final Resource resource, final ResourceStatus newStatus) {
         final List<Action> actions = Lists.newArrayList();
         if (shouldReload(resource)) {
diff --git a/plugins/org.eclipse.sirius/src/org/eclipse/sirius/business/internal/session/danalysis/SessionResourcesSynchronizer.java b/plugins/org.eclipse.sirius/src/org/eclipse/sirius/business/internal/session/danalysis/SessionResourcesSynchronizer.java
index 746d820da7..a0be802f98 100644
--- a/plugins/org.eclipse.sirius/src/org/eclipse/sirius/business/internal/session/danalysis/SessionResourcesSynchronizer.java
+++ b/plugins/org.eclipse.sirius/src/org/eclipse/sirius/business/internal/session/danalysis/SessionResourcesSynchronizer.java
@@ -91,6 +91,7 @@ public class SessionResourcesSynchronizer implements ResourceSyncClient {
                 case CONFLICTING_CHANGED:
                 case CONFLICTING_DELETED:
                 case DELETED:
+                case CHANGES_CANCELED:
                     IProgressMonitor pm = new NullProgressMonitor();
                     for (Resource resource : newStatuses.get(newStatus)) {
                         try {
@@ -175,7 +176,7 @@ public class SessionResourcesSynchronizer implements ResourceSyncClient {
             break;
         }
     }
-    
+
     private void reloadResource(final Resource resource) throws IOException {
         session.notifyListeners(SessionListener.ABOUT_TO_BE_REPLACED);
         TransactionalEditingDomain ted = session.getTransactionalEditingDomain();