eclipse-capella#2894 Avoid potential deadlocks in refresh

Change-Id: I653a0e579d58abf71f44ceb8eb85179cc07d5eb5
Signed-off-by: Maxime Porhel <[email protected]>

core/plugins/org.polarsys.capella.core.sirius.analysis/src/org/polarsys/capella/core/sirius/analysis/DiagramServices.java

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2006, 2023 THALES GLOBAL SERVICES.
+ * Copyright (c) 2006, 2024 THALES GLOBAL SERVICES and others.
  * 
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License 2.0 which is available at
@@ -9,6 +9,7 @@
  * 
  * Contributors:
  *    Thales - initial API and implementation
+ *    Maxime Porhel (Obeo) - Avoid potential deadlocks in refresh 
  *******************************************************************************/
 package org.polarsys.capella.core.sirius.analysis;
 
@@ -93,6 +94,8 @@
 import org.eclipse.sirius.ecore.extender.business.api.accessor.ModelAccessor;
 import org.eclipse.sirius.tools.api.SiriusPlugin;
 import org.eclipse.sirius.ui.business.api.dialect.DialectEditor;
+import org.eclipse.sirius.ui.business.api.session.IEditingSession;
+import org.eclipse.sirius.ui.business.api.session.SessionUIManager;
 import org.eclipse.sirius.viewpoint.DRepresentation;
 import org.eclipse.sirius.viewpoint.DSemanticDecorator;
 import org.eclipse.sirius.viewpoint.ViewpointPackage;
@@ -2100,13 +2103,20 @@ public void refreshRepresentationOfEditor(IEditorPart editor) {
    * @return
    */
   public EditPart getEditPart(DDiagramElement diagramElement) {
-    IEditorPart editor = EclipseUIUtil.getActiveEditor();
-    if (editor instanceof DiagramEditor) {
-      Session session = new EObjectQuery(diagramElement).getSession();
+    DDiagram parentDiagram = diagramElement == null ? null : diagramElement.getParentDiagram();
+    Session session = parentDiagram == null ? null : new EObjectQuery(parentDiagram).getSession();
+    IEditingSession uiSession = SessionUIManager.INSTANCE.getUISession(session);
+
+    DialectEditor editor = null;
+    if (uiSession != null && parentDiagram != null) {
+      editor = uiSession.getEditor(parentDiagram);
+    }
+
+    if (editor instanceof DiagramEditor diagramEditor) {
       View gmfView = SiriusGMFHelper.getGmfView(diagramElement, session);
 
-      if (gmfView != null && editor instanceof DiagramEditor) {
-        final Map<?, ?> editPartRegistry = ((DiagramEditor) editor).getDiagramGraphicalViewer().getEditPartRegistry();
+      if (gmfView != null && diagramEditor.getDiagramGraphicalViewer() != null) {
+        final Map<?, ?> editPartRegistry = diagramEditor.getDiagramGraphicalViewer().getEditPartRegistry();
         final Object editPart = editPartRegistry.get(gmfView);
         if (editPart instanceof EditPart) {
           return (EditPart) editPart;