eclipse-syson · jerome-obeo · Apr 24, 2026
diff --git a/backend/services/syson-services/src/main/java/org/eclipse/syson/services/UtilService.java b/backend/services/syson-services/src/main/java/org/eclipse/syson/services/UtilService.java
@@ -238,14 +238,28 @@ public List<StateUsage> getAllNonExhibitStates(Element element) {
      *
      * @param eObject
      *            the {@link EObject} stored in a {@link ResourceSet}
-     * @param type
+     * @param eClass
      *            the searched type, represented by its qualified name
      * @return a list of reachable object
      */
     public List<EObject> getAllReachable(EObject eObject, EClass eClass) {
         return this.getAllReachableType(eObject, eClass);
     }
 
+    /**
+     *  * Get all reachable elements of the type given by the {@link EClass} in the {@link ResourceSet} of the given type
+     * (represented by its qualified name) without considering elements inside standard libs.
+     *
+     * @param eObject
+     *            the {@link EObject} stored in a {@link ResourceSet}
+     * @param eClass
+     *            the searched type, represented by its qualified name
+     * @return a list of reachable object
+     */
+    public List<EObject> getAllReachableWithoutStandardLibs(EObject eObject, EClass eClass) {
+        return this.getAllReachableType(eObject, eClass, false);
+    }
+
     /**
      * Get all reachable elements of the type given by the {@link EClass} in the {@link ResourceSet} of the given
      * {@link EObject}.
@@ -605,6 +619,18 @@ public ActionUsage retrieveStandardStartAction(Element eObject) {
         return this.findByNameAndTypeInStandardLibraries(eObject, ActionUsage.class, "Actions::Action::start");
     }
 
+    /**
+     * Retrieve the start state defined inside the standard library <code>States</code>.
+     *
+     * @param eObject
+     *            an object to access to the library resources.
+     *
+     * @return the standard start StateUsage defined in the <code>States</code> library.
+     */
+    public StateUsage retrieveStandardStartState(Element eObject) {
+        return this.findByNameAndTypeInStandardLibraries(eObject, StateUsage.class, "States::StateAction::start");
+    }
+
     /**
      * Retrieve the done action defined inside the standard library <code>Actions</code>.
      *
@@ -617,6 +643,18 @@ public ActionUsage retrieveStandardDoneAction(Element eObject) {
         return this.findByNameAndTypeInStandardLibraries(eObject, ActionUsage.class, "Actions::Action::done");
     }
 
+    /**
+     * Retrieve the done state defined inside the standard library <code>States</code>.
+     *
+     * @param eObject
+     *            an object to access to the library resources.
+     *
+     * @return the standard done StateUsage defined in the <code>States</code> library.
+     */
+    public ActionUsage retrieveStandardDoneState(Element eObject) {
+        return this.findByNameAndTypeInStandardLibraries(eObject, ActionUsage.class, "States::StateAction::done");
+    }
+
     private <T extends Element> T findByNameAndTypeInStandardLibraries(Element context, Class<T> klass, String qualifiedName) {
         return context.eResource().getResourceSet().getResources().stream()
                 .flatMap(resource -> this.getLibraries(resource, true).stream())
@@ -1022,6 +1060,10 @@ public boolean isUnsynchronized(Element element) {
             isUnsynchronized = true;
         } else if (Objects.equals(element, this.retrieveStandardDoneAction(element))) {
             isUnsynchronized = true;
+        } else if (Objects.equals(element, this.retrieveStandardStartState(element))) {
+            isUnsynchronized = true;
+        } else if (Objects.equals(element, this.retrieveStandardDoneState(element))) {
+            isUnsynchronized = true;
         } else if (element instanceof NamespaceImport) {
             isUnsynchronized = true;
         } else if (element instanceof AnnotatingElement) {

diff --git a/...rg/eclipse/syson/diagram/common/view/edges/AbstractTransitionEdgeDescriptionProvider.java b/...rg/eclipse/syson/diagram/common/view/edges/AbstractTransitionEdgeDescriptionProvider.java
@@ -33,7 +33,9 @@
 import org.eclipse.sirius.components.view.diagram.NodeTool;
 import org.eclipse.sirius.components.view.diagram.SynchronizationPolicy;
 import org.eclipse.syson.diagram.common.view.nodes.DoneActionNodeDescriptionProvider;
+import org.eclipse.syson.diagram.common.view.nodes.DoneStateNodeDescriptionProvider;
 import org.eclipse.syson.diagram.common.view.nodes.StartActionNodeDescriptionProvider;
+import org.eclipse.syson.diagram.common.view.nodes.StartStateNodeDescriptionProvider;
 import org.eclipse.syson.diagram.common.view.services.ViewEdgeService;
 import org.eclipse.syson.diagram.services.aql.DiagramQueryAQLService;
 import org.eclipse.syson.services.UtilService;
@@ -73,7 +75,7 @@ public EdgeDescription create() {
                 .name(this.getEdgeDescriptionName())
                 .preconditionExpression(ServiceMethod.of2(ViewEdgeService::isInSameGraphicalContainer).aql(org.eclipse.sirius.components.diagrams.description.EdgeDescription.GRAPHICAL_EDGE_SOURCE,
                         org.eclipse.sirius.components.diagrams.description.EdgeDescription.GRAPHICAL_EDGE_TARGET, org.eclipse.sirius.components.diagrams.description.DiagramDescription.CACHE))
-                .semanticCandidatesExpression(ServiceMethod.of1(UtilService::getAllReachable).aqlSelf(domainType))
+                .semanticCandidatesExpression(ServiceMethod.of1(UtilService::getAllReachableWithoutStandardLibs).aqlSelf(domainType))
                 .sourceExpression(AQLConstants.AQL_SELF + "." + SysmlPackage.eINSTANCE.getTransitionUsage_Source().getName())
                 .style(this.createDefaultEdgeStyle())
                 .conditionalStyles(this.createStateConditionalStyle())
@@ -181,11 +183,13 @@ protected List<NodeDescription> getAllActionOrStateUsage(IViewDiagramElementFind
     }
 
     protected boolean isStartNode(NodeDescription n) {
-        return Objects.equals(this.getDescriptionNameGenerator().getNodeName(StartActionNodeDescriptionProvider.START_ACTION_NAME), n.getName());
+        return Objects.equals(this.getDescriptionNameGenerator().getNodeName(StartActionNodeDescriptionProvider.START_ACTION_NAME), n.getName()) ||
+                Objects.equals(this.getDescriptionNameGenerator().getNodeName(StartStateNodeDescriptionProvider.START_STATE_NAME), n.getName());
     }
 
     protected boolean isDoneNode(NodeDescription n) {
-        return Objects.equals(this.getDescriptionNameGenerator().getNodeName(DoneActionNodeDescriptionProvider.DONE_ACTION_NAME), n.getName());
+        return Objects.equals(this.getDescriptionNameGenerator().getNodeName(DoneActionNodeDescriptionProvider.DONE_ACTION_NAME), n.getName()) ||
+                Objects.equals(this.getDescriptionNameGenerator().getNodeName(DoneStateNodeDescriptionProvider.DONE_STATE_NAME), n.getName());
     }
 
     protected boolean isActionOrStateUsage(NodeDescription nodeDescription) {

diff --git a/...java/org/eclipse/syson/diagram/common/view/nodes/AbstractFakeNodeDescriptionProvider.java b/...java/org/eclipse/syson/diagram/common/view/nodes/AbstractFakeNodeDescriptionProvider.java
@@ -124,5 +124,9 @@ protected void addReusableCustomNodes(IViewDiagramElementFinder cache, List<Node
                 .ifPresent(childrenNodes::add);
         cache.getNodeDescription(this.descriptionNameGenerator.getNodeName(DoneActionNodeDescriptionProvider.DONE_ACTION_NAME))
                 .ifPresent(childrenNodes::add);
+        cache.getNodeDescription(this.descriptionNameGenerator.getNodeName(StartStateNodeDescriptionProvider.START_STATE_NAME))
+                .ifPresent(childrenNodes::add);
+        cache.getNodeDescription(this.descriptionNameGenerator.getNodeName(DoneStateNodeDescriptionProvider.DONE_STATE_NAME))
+                .ifPresent(childrenNodes::add);
     }
 }
diff --git a/...in/java/org/eclipse/syson/diagram/common/view/nodes/DoneStateNodeDescriptionProvider.java b/...in/java/org/eclipse/syson/diagram/common/view/nodes/DoneStateNodeDescriptionProvider.java
@@ -0,0 +1,77 @@
+/*******************************************************************************
+ * Copyright (c) 2024, 2026 Obeo.
+ * This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v2.0
+ * which accompanies this distribution, and is available at
+ * https://www.eclipse.org/legal/epl-2.0/
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ * Contributors:
+ *     Obeo - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.syson.diagram.common.view.nodes;
+
+import java.util.Objects;
+
+import org.eclipse.sirius.components.view.builder.IViewDiagramElementFinder;
+import org.eclipse.sirius.components.view.builder.providers.IColorProvider;
+import org.eclipse.sirius.components.view.diagram.DiagramDescription;
+import org.eclipse.sirius.components.view.diagram.NodeDescription;
+import org.eclipse.sirius.components.view.diagram.NodePalette;
+import org.eclipse.sirius.components.view.diagram.SynchronizationPolicy;
+import org.eclipse.sirius.components.view.diagram.UserResizableDirection;
+import org.eclipse.syson.services.UtilService;
+import org.eclipse.syson.sysml.SysmlPackage;
+import org.eclipse.syson.util.IDescriptionNameGenerator;
+import org.eclipse.syson.util.ServiceMethod;
+import org.eclipse.syson.util.SysMLMetamodelHelper;
+
+/**
+ * Used to create the ending node description of a state.
+ *
+ * @author Jerome Gout
+ */
+public class DoneStateNodeDescriptionProvider extends AbstractNodeDescriptionProvider {
+
+    public static final String DONE_STATE_NAME = "DoneState";
+
+    private final IDescriptionNameGenerator descriptionNameGenerator;
+
+    public DoneStateNodeDescriptionProvider(IColorProvider colorProvider, IDescriptionNameGenerator descriptionNameGenerator) {
+        super(colorProvider);
+        this.descriptionNameGenerator = Objects.requireNonNull(descriptionNameGenerator);
+    }
+
+    @Override
+    public NodeDescription create() {
+        String domainType = SysMLMetamodelHelper.buildQualifiedName(SysmlPackage.eINSTANCE.getStateUsage());
+        return this.diagramBuilderHelper.newNodeDescription()
+                .collapsible(false)
+                .domainType(domainType)
+                .defaultWidthExpression("36")
+                .defaultHeightExpression("36")
+                .name(this.descriptionNameGenerator.getNodeName(DONE_STATE_NAME))
+                .semanticCandidatesExpression(ServiceMethod.of0(UtilService::retrieveStandardDoneState).aqlSelf())
+                .style(this.createImageNodeStyleDescription("images/done_action.svg"))
+                .userResizable(UserResizableDirection.NONE)
+                .synchronizationPolicy(SynchronizationPolicy.UNSYNCHRONIZED)
+                .build();
+    }
+
+    @Override
+    public void link(DiagramDescription diagramDescription, IViewDiagramElementFinder cache) {
+        // this nodeDescription has not been added to the diagramDescription children but to the fakeNodeDescription
+        // children instead
+        cache.getNodeDescription(this.descriptionNameGenerator.getNodeName(DONE_STATE_NAME)).ifPresent(nodeDescription -> {
+            nodeDescription.setPalette(this.createNodePalette());
+        });
+    }
+
+    private NodePalette createNodePalette() {
+        return this.diagramBuilderHelper.newNodePalette()
+                .quickAccessTools(this.getDeleteFromDiagramTool())
+                .toolSections(this.defaultToolsFactory.createDefaultHideRevealNodeToolSection())
+                .build();
+    }
+}
diff --git a/...n/java/org/eclipse/syson/diagram/common/view/nodes/StartStateNodeDescriptionProvider.java b/...n/java/org/eclipse/syson/diagram/common/view/nodes/StartStateNodeDescriptionProvider.java
@@ -0,0 +1,109 @@
+/*******************************************************************************
+ * Copyright (c) 2024, 2026 Obeo.
+ * This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v2.0
+ * which accompanies this distribution, and is available at
+ * https://www.eclipse.org/legal/epl-2.0/
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ * Contributors:
+ *     Obeo - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.syson.diagram.common.view.nodes;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Objects;
+
+import org.eclipse.sirius.components.collaborative.diagrams.api.IDiagramService;
+import org.eclipse.sirius.components.core.api.IEditingContext;
+import org.eclipse.sirius.components.diagrams.description.EdgeDescription;
+import org.eclipse.sirius.components.view.builder.IViewDiagramElementFinder;
+import org.eclipse.sirius.components.view.builder.providers.IColorProvider;
+import org.eclipse.sirius.components.view.diagram.DiagramDescription;
+import org.eclipse.sirius.components.view.diagram.EdgeTool;
+import org.eclipse.sirius.components.view.diagram.NodeDescription;
+import org.eclipse.sirius.components.view.diagram.NodePalette;
+import org.eclipse.sirius.components.view.diagram.SynchronizationPolicy;
+import org.eclipse.sirius.components.view.diagram.UserResizableDirection;
+import org.eclipse.syson.diagram.common.view.services.ViewCreateService;
+import org.eclipse.syson.services.UtilService;
+import org.eclipse.syson.sysml.SysmlPackage;
+import org.eclipse.syson.util.IDescriptionNameGenerator;
+import org.eclipse.syson.util.ServiceMethod;
+import org.eclipse.syson.util.SysMLMetamodelHelper;
+
+/**
+ * Used to create the starting node description of a state.
+ *
+ * @author Jerome Gout
+ */
+public class StartStateNodeDescriptionProvider extends AbstractNodeDescriptionProvider {
+
+    public static final String START_STATE_NAME = "StartState";
+
+    private final IDescriptionNameGenerator descriptionNameGenerator;
+
+    public StartStateNodeDescriptionProvider(IColorProvider colorProvider, IDescriptionNameGenerator descriptionNameGenerator) {
+        super(colorProvider);
+        this.descriptionNameGenerator = Objects.requireNonNull(descriptionNameGenerator);
+    }
+
+    @Override
+    public NodeDescription create() {
+        String domainType = SysMLMetamodelHelper.buildQualifiedName(SysmlPackage.eINSTANCE.getStateUsage());
+        return this.diagramBuilderHelper.newNodeDescription()
+                .collapsible(false)
+                .domainType(domainType)
+                .defaultWidthExpression("28")
+                .defaultHeightExpression("28")
+                .name(this.descriptionNameGenerator.getNodeName(START_STATE_NAME))
+                .semanticCandidatesExpression(ServiceMethod.of0(UtilService::retrieveStandardStartState).aqlSelf())
+                .style(this.createImageNodeStyleDescription("images/start_action.svg"))
+                .userResizable(UserResizableDirection.NONE)
+                .synchronizationPolicy(SynchronizationPolicy.UNSYNCHRONIZED)
+                .build();
+    }
+
+    @Override
+    public void link(DiagramDescription diagramDescription, IViewDiagramElementFinder cache) {
+        // this nodeDescription has not been added to the diagramDescription children but to the fakeNodeDescription
+        // children instead
+        cache.getNodeDescription(this.descriptionNameGenerator.getNodeName(START_STATE_NAME)).ifPresent(nodeDescription -> {
+            nodeDescription.setPalette(this.createNodePalette(cache));
+        });
+    }
+
+    private NodePalette createNodePalette(IViewDiagramElementFinder cache) {
+        var edgeTools = new ArrayList<EdgeTool>(this.getEdgeTools(cache));
+
+        return this.diagramBuilderHelper.newNodePalette()
+                .edgeTools(edgeTools.toArray(EdgeTool[]::new))
+                .quickAccessTools(this.getDeleteFromDiagramTool())
+                .toolSections(this.defaultToolsFactory.createDefaultHideRevealNodeToolSection())
+                .build();
+    }
+
+    private List<EdgeTool> getEdgeTools(IViewDiagramElementFinder cache) {
+        var targetElementDescriptions = this.getStartTargetDescriptions(cache);
+
+        var createStartEdgeTool = this.diagramBuilderHelper.newEdgeTool().name(this.descriptionNameGenerator.getCreationToolName(SysmlPackage.eINSTANCE.getTransitionUsage()))
+                .iconURLsExpression("/icons/full/obj16/TransitionUsage.svg")
+                .body(this.viewBuilderHelper.newChangeContext()
+                        .expression(
+                                ServiceMethod.of5(ViewCreateService::createTransitionUsage).aql(EdgeDescription.SEMANTIC_EDGE_SOURCE, EdgeDescription.SEMANTIC_EDGE_TARGET, EdgeDescription.EDGE_SOURCE,
+                                        EdgeDescription.EDGE_TARGET, IEditingContext.EDITING_CONTEXT, IDiagramService.DIAGRAM_SERVICES))
+                        .build())
+                .targetElementDescriptions(targetElementDescriptions.toArray(NodeDescription[]::new))
+                .build();
+
+        return List.of(createStartEdgeTool);
+    }
+
+    private List<NodeDescription> getStartTargetDescriptions(IViewDiagramElementFinder cache) {
+        var targets = new ArrayList<NodeDescription>();
+        cache.getNodeDescription(this.descriptionNameGenerator.getNodeName(SysmlPackage.eINSTANCE.getStateUsage())).ifPresent(targets::add);
+        return targets;
+    }
+}
diff --git a/...se/syson/diagram/common/view/nodes/StateTransitionCompartmentNodeDescriptionProvider.java b/...se/syson/diagram/common/view/nodes/StateTransitionCompartmentNodeDescriptionProvider.java
@@ -32,6 +32,8 @@
 import org.eclipse.sirius.components.view.diagram.SynchronizationPolicy;
 import org.eclipse.sirius.components.view.diagram.UserResizableDirection;
 import org.eclipse.syson.diagram.common.view.services.description.ToolConstants;
+import org.eclipse.syson.diagram.common.view.tools.DoneStateNodeToolProvider;
+import org.eclipse.syson.diagram.common.view.tools.StartStateNodeToolProvider;
 import org.eclipse.syson.diagram.common.view.tools.StateTransitionCompartmentNodeToolProvider;
 import org.eclipse.syson.sysml.SysmlPackage;
 import org.eclipse.syson.util.AQLConstants;
@@ -76,6 +78,8 @@ public void link(DiagramDescription diagramDescription, IViewDiagramElementFinde
         cache.getNodeDescription(this.name).ifPresent(nodeDescription -> {
             cache.getNodeDescription(this.getDescriptionNameGenerator().getNodeName(SysmlPackage.eINSTANCE.getStateUsage())).ifPresent(nodeDescription.getReusedChildNodeDescriptions()::add);
             cache.getNodeDescription(this.getDescriptionNameGenerator().getNodeName(SysmlPackage.eINSTANCE.getStateDefinition())).ifPresent(nodeDescription.getReusedChildNodeDescriptions()::add);
+            cache.getNodeDescription(this.getDescriptionNameGenerator().getNodeName(StartStateNodeDescriptionProvider.START_STATE_NAME)).ifPresent(nodeDescription.getReusedChildNodeDescriptions()::add);
+            cache.getNodeDescription(this.getDescriptionNameGenerator().getNodeName(DoneStateNodeDescriptionProvider.DONE_STATE_NAME)).ifPresent(nodeDescription.getReusedChildNodeDescriptions()::add);
             nodeDescription.setPalette(this.createCompartmentPalette(cache));
         });
     }
@@ -117,6 +121,8 @@ protected NodePalette createCompartmentPalette(IViewDiagramElementFinder cache)
         var toolSections = this.toolDescriptionService.createDefaultNodeToolSections();
 
         // Do not use getItemCreationToolProvider because the compartment contains multiple creation tools.
+        this.toolDescriptionService.addNodeTool(toolSections, ToolConstants.BEHAVIOR, new StartStateNodeToolProvider(this.eClass, this.getDescriptionNameGenerator()).create(cache));
+        this.toolDescriptionService.addNodeTool(toolSections, ToolConstants.BEHAVIOR, new DoneStateNodeToolProvider(this.eClass, this.getDescriptionNameGenerator()).create(cache));
         this.toolDescriptionService.addNodeTool(toolSections, ToolConstants.BEHAVIOR, new StateTransitionCompartmentNodeToolProvider(false, false).create(cache));
         this.toolDescriptionService.addNodeTool(toolSections, ToolConstants.BEHAVIOR, new StateTransitionCompartmentNodeToolProvider(true, false).create(cache));
         this.toolDescriptionService.addNodeTool(toolSections, ToolConstants.BEHAVIOR, new StateTransitionCompartmentNodeToolProvider(false, true).create(cache));