From 0ef0a7ee9f66651b263defa140f0e98c917c0c55 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Markus=20Hegedu=CC=88s?= <markus.hegedues@prewave.ai>
Date: Fri, 21 Apr 2023 11:49:40 +0200
Subject: [PATCH 1/8] implement subclientId for server reload logic for
 RequestModelAction replace commandStack with commandStackManager

---
 .../glsp/server/emf/EMFModelState.java        | 17 ++++--
 .../server/emf/EMFSourceModelStorage.java     |  6 +--
 .../eclipse/glsp/server/actions/Action.java   | 20 ++++++-
 .../actions/SaveModelActionHandler.java       |  4 +-
 .../eclipse/glsp/server/di/DiagramModule.java | 16 ++++++
 .../model/ComputedBoundsActionHandler.java    |  2 +-
 .../core/model/ModelSubmissionHandler.java    | 20 +++----
 .../core/model/RequestModelActionHandler.java | 16 +++---
 .../undoredo/UndoRedoActionHandler.java       | 12 ++---
 .../actions/DefaultActionDispatcher.java      |  1 +
 .../internal/command/CommandStackFactory.java |  7 +++
 .../internal/command/CommandStackManager.java | 13 +++++
 .../command/DefaultCommandStackManager.java   | 53 +++++++++++++++++++
 .../GModelCommandStackFactory.java            | 11 ++++
 .../glsp/server/model/DefaultGModelState.java | 39 ++++++++------
 .../glsp/server/model/GModelState.java        |  4 +-
 .../eclipse/glsp/server/model/ModelState.java | 10 ++--
 .../operations/OperationActionHandler.java    | 12 ++---
 .../server/protocol/DefaultGLSPServer.java    |  2 +
 .../glsp/server/utils/ClientOptionsUtil.java  | 10 ++++
 .../glsp/server/utils/CollaborateUtil.java    |  5 ++
 21 files changed, 218 insertions(+), 62 deletions(-)
 create mode 100644 plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/command/CommandStackFactory.java
 create mode 100644 plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/command/CommandStackManager.java
 create mode 100644 plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/command/DefaultCommandStackManager.java
 create mode 100644 plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/gmodel/commandstack/GModelCommandStackFactory.java
 create mode 100644 plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/utils/CollaborateUtil.java

diff --git a/plugins/org.eclipse.glsp.server.emf/src/org/eclipse/glsp/server/emf/EMFModelState.java b/plugins/org.eclipse.glsp.server.emf/src/org/eclipse/glsp/server/emf/EMFModelState.java
index e906b722..7286db4d 100644
--- a/plugins/org.eclipse.glsp.server.emf/src/org/eclipse/glsp/server/emf/EMFModelState.java
+++ b/plugins/org.eclipse.glsp.server.emf/src/org/eclipse/glsp/server/emf/EMFModelState.java
@@ -17,6 +17,7 @@
 
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
+import org.eclipse.emf.common.command.BasicCommandStack;
 import org.eclipse.emf.common.command.CommandStack;
 import org.eclipse.emf.common.util.EList;
 import org.eclipse.emf.ecore.resource.Resource;
@@ -24,6 +25,7 @@
 import org.eclipse.emf.edit.domain.EditingDomain;
 import org.eclipse.glsp.graph.GModelIndex;
 import org.eclipse.glsp.graph.GModelRoot;
+import org.eclipse.glsp.server.internal.command.CommandStackManager;
 import org.eclipse.glsp.server.model.DefaultGModelState;
 import org.eclipse.glsp.server.session.ClientSession;
 import org.eclipse.glsp.server.session.ClientSessionListener;
@@ -51,6 +53,9 @@ public class EMFModelState extends DefaultGModelState implements ClientSessionLi
    @Inject
    protected EMFIdGenerator idGenerator;
 
+   @Inject
+   protected CommandStackManager commandStackManager;
+
    protected EditingDomain editingDomain;
 
    @Override
@@ -59,9 +64,9 @@ public void init() {
       this.clientSessionManager.addListener(this, this.clientId);
    }
 
-   public void setEditingDomain(final EditingDomain editingDomain) {
+   public void setEditingDomain(final EditingDomain editingDomain, final String subclientId) {
       this.editingDomain = editingDomain;
-      setCommandStack(this.editingDomain.getCommandStack());
+      commandStackManager.setCommandStack(this.editingDomain.getCommandStack(), subclientId);
    }
 
    public EditingDomain getEditingDomain() { return editingDomain; }
@@ -102,8 +107,12 @@ protected void closeResourceSet() {
          }
       }
       if (result) {
-         commandStack.flush();
-         saveIsDone();
+         commandStackManager.getAllCommandStack().forEach(commandStack -> {
+            commandStack.flush();
+            if (commandStack instanceof BasicCommandStack) {
+               ((BasicCommandStack) commandStack).saveIsDone();
+            }
+         });
       }
    }
 
diff --git a/plugins/org.eclipse.glsp.server.emf/src/org/eclipse/glsp/server/emf/EMFSourceModelStorage.java b/plugins/org.eclipse.glsp.server.emf/src/org/eclipse/glsp/server/emf/EMFSourceModelStorage.java
index 5b24f3cf..d467454c 100644
--- a/plugins/org.eclipse.glsp.server.emf/src/org/eclipse/glsp/server/emf/EMFSourceModelStorage.java
+++ b/plugins/org.eclipse.glsp.server.emf/src/org/eclipse/glsp/server/emf/EMFSourceModelStorage.java
@@ -56,17 +56,17 @@ public void loadSourceModel(final RequestModelAction action) {
          .orElseThrow(() -> new GLSPServerException("No source URI given to load model!"));
       URI resourceURI = URI.createFileURI(sourceURI);
 
-      EditingDomain editingDomain = getOrCreateEditingDomain();
+      EditingDomain editingDomain = getOrCreateEditingDomain(action.getSubclientId());
       doLoadSourceModel(editingDomain.getResourceSet(), resourceURI, action);
    }
 
-   protected EditingDomain getOrCreateEditingDomain() {
+   protected EditingDomain getOrCreateEditingDomain(final String subclientId) {
       if (modelState.getEditingDomain() != null) {
          return modelState.getEditingDomain();
       }
       EditingDomain editingDomain = editingDomainFactory.createEditingDomain();
       setupResourceSet(editingDomain.getResourceSet());
-      modelState.setEditingDomain(editingDomain);
+      modelState.setEditingDomain(editingDomain, subclientId);
       return editingDomain;
    }
 
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/actions/Action.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/actions/Action.java
index 7d981b17..b2eaed92 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/actions/Action.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/actions/Action.java
@@ -15,6 +15,8 @@
  ********************************************************************************/
 package org.eclipse.glsp.server.actions;
 
+import org.eclipse.glsp.server.internal.util.GenericsUtil;
+
 /**
  * Java-implementation of the `Action` interface. An action is a declarative description of a behavior that
  * shall be
@@ -31,13 +33,22 @@ public abstract class Action {
     */
    private final String kind;
 
-   public Action(final String kind) {
+   private String subclientId;
+
+   public Action(final String kind, final String subclientId) {
       super();
       this.kind = kind;
+      this.subclientId = subclientId;
+   }
+
+   public Action(final String kind) {
+      this(kind, null);
    }
 
    public String getKind() { return kind; }
 
+   public String getSubclientId() { return subclientId; }
+
    @Override
    public String toString() {
       StringBuilder builder = new StringBuilder();
@@ -47,4 +58,11 @@ public String toString() {
       return builder.toString();
    }
 
+   public static Action addSubclientId(final Action initialAction, final Action extendedAction) {
+      if (initialAction.getSubclientId() != null) {
+         extendedAction.subclientId = initialAction.subclientId;
+      }
+      return extendedAction;
+   }
+
 }
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/actions/SaveModelActionHandler.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/actions/SaveModelActionHandler.java
index 4bd58ea2..44c72bdf 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/actions/SaveModelActionHandler.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/actions/SaveModelActionHandler.java
@@ -45,11 +45,11 @@ public List<Action> executeAction(final SaveModelAction action) {
       modelSourceWatcher.ifPresent(watcher -> watcher.pauseWatching());
       try {
          sourceModelStorage.saveSourceModel(action);
-         modelState.saveIsDone();
+         modelState.saveIsDone(action.getSubclientId());
       } finally {
          modelSourceWatcher.ifPresent(watcher -> watcher.continueWatching());
       }
-      return listOf(new SetDirtyStateAction(modelState.isDirty(), SetDirtyStateAction.Reason.SAVE));
+      return listOf(new SetDirtyStateAction(modelState.isDirty(action.getSubclientId()), SetDirtyStateAction.Reason.SAVE));
    }
 
 }
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/di/DiagramModule.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/di/DiagramModule.java
index 5fa2ccd2..00787b4f 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/di/DiagramModule.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/di/DiagramModule.java
@@ -87,10 +87,14 @@
 import org.eclipse.glsp.server.gson.GraphGsonConfigurationFactory;
 import org.eclipse.glsp.server.internal.actions.DefaultActionDispatcher;
 import org.eclipse.glsp.server.internal.actions.DefaultActionHandlerRegistry;
+import org.eclipse.glsp.server.internal.command.CommandStackFactory;
+import org.eclipse.glsp.server.internal.command.CommandStackManager;
+import org.eclipse.glsp.server.internal.command.DefaultCommandStackManager;
 import org.eclipse.glsp.server.internal.diagram.DefaultServerConfigurationContribution;
 import org.eclipse.glsp.server.internal.featues.directediting.DefaultContextEditValidatorRegistry;
 import org.eclipse.glsp.server.internal.featues.navigation.DefaultNavigationTargetProviderRegistry;
 import org.eclipse.glsp.server.internal.features.contextactions.DefaultContextActionsProviderRegistry;
+import org.eclipse.glsp.server.internal.gmodel.commandstack.GModelCommandStackFactory;
 import org.eclipse.glsp.server.internal.gson.DefaultGraphGsonConfigurationFactory;
 import org.eclipse.glsp.server.internal.operations.DefaultOperationHandlerRegistry;
 import org.eclipse.glsp.server.internal.toolpalette.DefaultToolPaletteItemProvider;
@@ -210,6 +214,10 @@ protected void configureBase() {
       bindOptionally(PopupModelFactory.class, bindPopupModelFactory());
       bindOptionally(LayoutEngine.class, bindLayoutEngine());
       bindOptionally(GraphExtension.class, bindGraphExtension());
+
+      // Command Stack
+      bind(CommandStackFactory.class).to(bindCommandStackFactory()).in(Singleton.class);
+      bind(CommandStackManager.class).to(bindCommandStackManager()).in(Singleton.class);
    }
 
    protected void bindDiagramType() {
@@ -372,5 +380,13 @@ protected Class<? extends GraphExtension> bindGraphExtension() {
       return null;
    }
 
+   protected Class<? extends CommandStackFactory> bindCommandStackFactory() {
+      return GModelCommandStackFactory.class;
+   }
+
+   protected Class<? extends CommandStackManager> bindCommandStackManager() {
+      return DefaultCommandStackManager.class;
+   }
+
    public abstract String getDiagramType();
 }
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/features/core/model/ComputedBoundsActionHandler.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/features/core/model/ComputedBoundsActionHandler.java
index d4be507d..8c58d234 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/features/core/model/ComputedBoundsActionHandler.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/features/core/model/ComputedBoundsActionHandler.java
@@ -45,7 +45,7 @@ public List<Action> executeAction(final ComputedBoundsAction action) {
          if (model != null && action.getRevision().isPresent()
             && action.getRevision().get().doubleValue() == model.getRevision()) {
             LayoutUtil.applyBounds(model, action, modelState);
-            return submissionHandler.submitModelDirectly();
+            return submissionHandler.submitModelDirectly(action.getSubclientId());
          }
       }
       return none();
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/features/core/model/ModelSubmissionHandler.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/features/core/model/ModelSubmissionHandler.java
index 8da40c65..002f2dfb 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/features/core/model/ModelSubmissionHandler.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/features/core/model/ModelSubmissionHandler.java
@@ -61,28 +61,28 @@ public class ModelSubmissionHandler {
     * @param reason The optional reason that caused the model update.
     * @return A list of actions to be processed in order to submit the model.
     */
-   public List<Action> submitModel(final String reason) {
+   public List<Action> submitModel(final String reason, final String subclientId) {
       modelFactory.createGModel();
       modelState.getRoot().setRevision(modelState.getRoot().getRevision() + 1);
       boolean needsClientLayout = diagramConfiguration.needsClientLayout();
       if (needsClientLayout) {
          synchronized (modelLock) {
             return Arrays.asList(new RequestBoundsAction(modelState.getRoot()),
-               new SetDirtyStateAction(modelState.isDirty(), reason));
+               new SetDirtyStateAction(modelState.isDirty(subclientId), reason));
          }
       }
-      return submitModelDirectly(reason);
+      return submitModelDirectly(reason, subclientId);
    }
 
-   public List<Action> submitModel() {
-      return submitModel(null);
+   public List<Action> submitModel(final String subclientId) {
+      return submitModel(null, subclientId);
    }
 
    /**
     * Returns a list of actions to directly update the client-side model without any server- or client-side layouting.
     * <p>
     * Typically {@link ActionHandler action handlers} don't invoke this method but use
-    * {@link #submitModel(String)}
+    * {@link #submitModel(String, String)}
     * instead, as this is only used to eventually submit the model on the client directly after all layouting is already
     * performed before. The only foreseen caller of this method is {@link ComputedBoundsActionHandler}.
     * </p>
@@ -95,7 +95,7 @@ public List<Action> submitModel() {
     * @param reason The optional reason that caused the model update.
     * @return A list of actions to be processed in order to submit the model.
     */
-   public List<Action> submitModelDirectly(final String reason) {
+   public List<Action> submitModelDirectly(final String reason, final String subclientId) {
       GModelRoot gModel = modelState.getRoot();
       if (diagramConfiguration.getLayoutKind() == ServerLayoutKind.AUTOMATIC && layoutEngine.isPresent()) {
          layoutEngine.get().layout();
@@ -106,14 +106,14 @@ public List<Action> submitModelDirectly(final String reason) {
          List<Action> result = new ArrayList<>();
          result.add(modelAction);
          if (!diagramConfiguration.needsClientLayout()) {
-            result.add(new SetDirtyStateAction(modelState.isDirty(), reason));
+            result.add(new SetDirtyStateAction(modelState.isDirty(subclientId), reason));
          }
          return result;
       }
    }
 
-   public List<Action> submitModelDirectly() {
-      return submitModelDirectly(null);
+   public List<Action> submitModelDirectly(final String subclientId) {
+      return submitModelDirectly(null, subclientId);
    }
 
    public synchronized Object getModelLock() { return modelLock; }
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/features/core/model/RequestModelActionHandler.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/features/core/model/RequestModelActionHandler.java
index c40007d4..aaaef886 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/features/core/model/RequestModelActionHandler.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/features/core/model/RequestModelActionHandler.java
@@ -24,6 +24,7 @@
 import org.eclipse.glsp.server.di.DiagramModule;
 import org.eclipse.glsp.server.features.sourcemodelwatcher.SourceModelWatcher;
 import org.eclipse.glsp.server.model.GModelState;
+import org.eclipse.glsp.server.utils.ClientOptionsUtil;
 import org.eclipse.glsp.server.utils.ServerMessageUtil;
 import org.eclipse.glsp.server.utils.ServerStatusUtil;
 
@@ -58,15 +59,18 @@ public class RequestModelActionHandler extends AbstractActionHandler<RequestMode
 
    @Override
    public List<Action> executeAction(final RequestModelAction action) {
-      modelState.setClientOptions(action.getOptions());
+      // only reload if not initialized
+      if (!ClientOptionsUtil.disableReloadIsTrue(action.getOptions()) || modelState.getRoot() == null) {
+         modelState.setClientOptions(action.getOptions());
 
-      notifyStartLoading();
-      sourceModelStorage.loadSourceModel(action);
-      notifyFinishedLoading();
+         notifyStartLoading();
+         sourceModelStorage.loadSourceModel(action);
+         notifyFinishedLoading();
 
-      sourceModelWatcher.ifPresent(watcher -> watcher.startWatching());
+         sourceModelWatcher.ifPresent(watcher -> watcher.startWatching());
+      }
 
-      return modelSubmissionHandler.submitModel();
+      return modelSubmissionHandler.submitModel(action.getSubclientId());
    }
 
    protected void notifyStartLoading() {
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/features/undoredo/UndoRedoActionHandler.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/features/undoredo/UndoRedoActionHandler.java
index fd203908..ddb94d75 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/features/undoredo/UndoRedoActionHandler.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/features/undoredo/UndoRedoActionHandler.java
@@ -39,12 +39,12 @@ public class UndoRedoActionHandler implements ActionHandler {
 
    @Override
    public List<Action> execute(final Action action) {
-      if (action instanceof UndoAction && modelState.canUndo()) {
-         modelState.undo();
-         return modelSubmissionHandler.submitModel(SetDirtyStateAction.Reason.UNDO);
-      } else if (action instanceof RedoAction && modelState.canRedo()) {
-         modelState.redo();
-         return modelSubmissionHandler.submitModel(SetDirtyStateAction.Reason.REDO);
+      if (action instanceof UndoAction && modelState.canUndo(action.getSubclientId())) {
+         modelState.undo(action.getSubclientId());
+         return modelSubmissionHandler.submitModel(SetDirtyStateAction.Reason.UNDO, action.getSubclientId());
+      } else if (action instanceof RedoAction && modelState.canRedo(action.getSubclientId())) {
+         modelState.redo(action.getSubclientId());
+         return modelSubmissionHandler.submitModel(SetDirtyStateAction.Reason.REDO, action.getSubclientId());
       }
       LOGGER.warn("Cannot undo or redo");
       return none();
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/actions/DefaultActionDispatcher.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/actions/DefaultActionDispatcher.java
index 03d87259..4a05493c 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/actions/DefaultActionDispatcher.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/actions/DefaultActionDispatcher.java
@@ -192,6 +192,7 @@ protected List<CompletableFuture<Void>> runAction(final Action action) {
       for (final ActionHandler actionHandler : actionHandlers) {
          final List<Action> responses = actionHandler.execute(action).stream()
             .map(response -> ResponseAction.respond(action, response))
+            .map(response -> Action.addSubclientId(action, response))
             .collect(Collectors.toList());
          results.addAll(dispatchAll(responses));
          if (action instanceof UpdateModelAction) {
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/command/CommandStackFactory.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/command/CommandStackFactory.java
new file mode 100644
index 00000000..9fa927ad
--- /dev/null
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/command/CommandStackFactory.java
@@ -0,0 +1,7 @@
+package org.eclipse.glsp.server.internal.command;
+
+import org.eclipse.emf.common.command.CommandStack;
+
+public interface CommandStackFactory {
+    CommandStack createCommandStack();
+}
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/command/CommandStackManager.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/command/CommandStackManager.java
new file mode 100644
index 00000000..bc9f8fa2
--- /dev/null
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/command/CommandStackManager.java
@@ -0,0 +1,13 @@
+package org.eclipse.glsp.server.internal.command;
+
+import org.eclipse.emf.common.command.CommandStack;
+
+import java.util.List;
+
+public interface CommandStackManager {
+    CommandStack getOrCreateCommandStack(String subclientId);
+
+    List<CommandStack> getAllCommandStack();
+
+    void setCommandStack(CommandStack commandStack, String subclientId);
+}
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/command/DefaultCommandStackManager.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/command/DefaultCommandStackManager.java
new file mode 100644
index 00000000..d734100b
--- /dev/null
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/command/DefaultCommandStackManager.java
@@ -0,0 +1,53 @@
+package org.eclipse.glsp.server.internal.command;
+
+import com.google.inject.Inject;
+import org.eclipse.emf.common.command.CommandStack;
+import org.eclipse.glsp.server.utils.CollaborateUtil;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+public class DefaultCommandStackManager implements CommandStackManager {
+
+    @Inject
+    CommandStackFactory factory;
+
+    // subclientId, CommandStack
+    protected Map<String, CommandStack> commandStackMap = new HashMap<>();
+
+    @Override
+    public CommandStack getOrCreateCommandStack(final String subclientId) {
+        String subclientIdOrFallback = getSubclientIdOrFallback(subclientId);
+        if (commandStackMap.containsKey(subclientIdOrFallback)) {
+            return commandStackMap.get(getSubclientIdOrFallback(subclientIdOrFallback));
+        }
+
+        CommandStack commandStack = factory.createCommandStack();
+        commandStackMap.put(subclientIdOrFallback, commandStack);
+        return commandStack;
+    }
+
+    @Override
+    public List<CommandStack> getAllCommandStack() {
+        return new ArrayList<>(commandStackMap.values());
+    }
+
+    @Override
+    public void setCommandStack(final CommandStack commandStack, final String subclientId) {
+        String subclientIdOrFallback = getSubclientIdOrFallback(subclientId);
+        if (commandStackMap.containsKey(subclientIdOrFallback)) {
+            commandStackMap.get(subclientIdOrFallback).flush();
+        }
+        commandStackMap.put(subclientIdOrFallback, commandStack);
+    }
+
+    private String getSubclientIdOrFallback(final String subclientId) {
+        if (subclientId != null) {
+            return subclientId;
+        }
+        return CollaborateUtil.FALLBACK_SUBCLIENT_ID;
+    }
+
+}
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/gmodel/commandstack/GModelCommandStackFactory.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/gmodel/commandstack/GModelCommandStackFactory.java
new file mode 100644
index 00000000..4b280354
--- /dev/null
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/gmodel/commandstack/GModelCommandStackFactory.java
@@ -0,0 +1,11 @@
+package org.eclipse.glsp.server.internal.gmodel.commandstack;
+
+import org.eclipse.emf.common.command.CommandStack;
+import org.eclipse.glsp.server.internal.command.CommandStackFactory;
+
+public class GModelCommandStackFactory implements CommandStackFactory  {
+    @Override
+    public CommandStack createCommandStack() {
+        return new GModelCommandStack();
+    }
+}
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/model/DefaultGModelState.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/model/DefaultGModelState.java
index ef66fb54..5a061640 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/model/DefaultGModelState.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/model/DefaultGModelState.java
@@ -25,26 +25,33 @@
 import org.eclipse.glsp.graph.GModelIndex;
 import org.eclipse.glsp.graph.GModelRoot;
 import org.eclipse.glsp.server.di.ClientId;
+import org.eclipse.glsp.server.internal.command.CommandStackManager;
 import org.eclipse.glsp.server.internal.gmodel.commandstack.GModelCommandStack;
 
 import com.google.inject.Inject;
 
 public class DefaultGModelState implements GModelState {
 
+   public DefaultGModelState() {
+      System.out.println("test");
+   }
+
    @Inject
    @ClientId
    protected String clientId;
 
+   @Inject
+   protected CommandStackManager commandStackManager;
+
    protected Map<String, String> options;
    protected final Map<String, Object> properties = new HashMap<>();
    protected GModelRoot currentModel;
-   protected CommandStack commandStack;
    protected String editMode;
    protected GModelIndex index = GModelIndex.empty();
 
    @Inject
    public void init() {
-      setCommandStack(new GModelCommandStack());
+      commandStackManager.setCommandStack(new GModelCommandStack(), null);
    }
 
    @Override
@@ -71,13 +78,6 @@ protected GModelIndex getOrUpdateIndex(final GModelRoot newRoot) {
 
    protected void setRoot(final GModelRoot newRoot) { this.currentModel = newRoot; }
 
-   protected void setCommandStack(final CommandStack commandStack) {
-      if (this.commandStack != null) {
-         this.commandStack.flush();
-      }
-      this.commandStack = commandStack;
-   }
-
    @Override
    public void setClientOptions(final Map<String, String> options) { this.options = options; }
 
@@ -85,43 +85,50 @@ protected void setCommandStack(final CommandStack commandStack) {
    public GModelIndex getIndex() { return index; }
 
    @Override
-   public void execute(final Command command) {
+   public void execute(final Command command, String subclientId) {
+      CommandStack commandStack = commandStackManager.getOrCreateCommandStack(subclientId);
       if (commandStack != null) {
          commandStack.execute(command);
       }
    }
 
    @Override
-   public boolean canUndo() {
+   public boolean canUndo(final String subclientId) {
+      CommandStack commandStack = commandStackManager.getOrCreateCommandStack(subclientId);
       return commandStack != null && commandStack.canUndo();
    }
 
    @Override
-   public boolean canRedo() {
+   public boolean canRedo(final String subclientId) {
+      CommandStack commandStack = commandStackManager.getOrCreateCommandStack(subclientId);
       return commandStack != null && commandStack.canRedo();
    }
 
    @Override
-   public void undo() {
+   public void undo(final String subclientId) {
+      CommandStack commandStack = commandStackManager.getOrCreateCommandStack(subclientId);
       if (commandStack != null) {
          commandStack.undo();
       }
    }
 
    @Override
-   public void redo() {
+   public void redo(final String subclientId) {
+      CommandStack commandStack = commandStackManager.getOrCreateCommandStack(subclientId);
       if (commandStack != null) {
          commandStack.redo();
       }
    }
 
    @Override
-   public boolean isDirty() {
+   public boolean isDirty(final String subclientId) {
+      CommandStack commandStack = commandStackManager.getOrCreateCommandStack(subclientId);
       return commandStack instanceof BasicCommandStack && ((BasicCommandStack) commandStack).isSaveNeeded();
    }
 
    @Override
-   public void saveIsDone() {
+   public void saveIsDone(final String subclientId) {
+      CommandStack commandStack = commandStackManager.getOrCreateCommandStack(subclientId);
       if (commandStack instanceof BasicCommandStack) {
          ((BasicCommandStack) commandStack).saveIsDone();
       }
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/model/GModelState.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/model/GModelState.java
index e9ea274d..70ffa118 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/model/GModelState.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/model/GModelState.java
@@ -36,12 +36,12 @@ public interface GModelState extends ModelState<GModelRoot> {
    /**
     * Called after a save has been successfully performed.
     */
-   void saveIsDone();
+   void saveIsDone(String subclientId);
 
    /**
     * Uses its {@link BasicCommandStack} to execute a given {@link Command}.
     *
     * @param command The {@link Command} to be executed.
     */
-   void execute(Command command);
+   void execute(Command command, String subclientId);
 }
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/model/ModelState.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/model/ModelState.java
index 0a9598ff..731dcc79 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/model/ModelState.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/model/ModelState.java
@@ -34,15 +34,15 @@ interface ModelState<T> {
 
    void updateRoot(T newRoot);
 
-   boolean canUndo();
+   boolean canUndo(String subclientId);
 
-   boolean canRedo();
+   boolean canRedo(String subclientId);
 
-   void undo();
+   void undo(String subclientId);
 
-   void redo();
+   void redo(String subclientId);
 
-   boolean isDirty();
+   boolean isDirty(String subclientId);
 
    String getEditMode();
 
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/operations/OperationActionHandler.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/operations/OperationActionHandler.java
index 30b0d059..6e56c867 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/operations/OperationActionHandler.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/operations/OperationActionHandler.java
@@ -62,18 +62,18 @@ protected List<Action> executeOperation(final Operation operation) {
    protected List<Action> executeHandler(final Operation operation, final OperationHandler<?> handler) {
       Optional<Command> command = handler.execute(operation);
       if (command.isPresent()) {
-         exexcuteCommand(command.get());
-         return submitModel();
+         exexcuteCommand(command.get(), operation.getSubclientId());
+         return submitModel(operation.getSubclientId());
       }
       return none();
    }
 
-   protected void exexcuteCommand(final Command command) {
-      modelState.execute(command);
+   protected void exexcuteCommand(final Command command, final String subclientId) {
+      modelState.execute(command, subclientId);
    }
 
-   protected List<Action> submitModel() {
-      return modelSubmissionHandler.submitModel(SetDirtyStateAction.Reason.OPERATION);
+   protected List<Action> submitModel(final String subclientId) {
+      return modelSubmissionHandler.submitModel(SetDirtyStateAction.Reason.OPERATION, subclientId);
    }
 
    /**
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/protocol/DefaultGLSPServer.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/protocol/DefaultGLSPServer.java
index 5903d988..3fa50fd7 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/protocol/DefaultGLSPServer.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/protocol/DefaultGLSPServer.java
@@ -28,6 +28,7 @@
 import org.apache.logging.log4j.Logger;
 import org.eclipse.glsp.server.actions.ActionMessage;
 import org.eclipse.glsp.server.actions.ActionRegistry;
+import org.eclipse.glsp.server.model.GModelState;
 import org.eclipse.glsp.server.session.ClientSession;
 import org.eclipse.glsp.server.session.ClientSessionManager;
 import org.eclipse.glsp.server.types.GLSPServerException;
@@ -120,6 +121,7 @@ public CompletableFuture<Void> initializeClientSession(final InitializeClientSes
          ClientSession session = sessionManager.getOrCreateClientSession(params.getClientSessionId(),
             params.getDiagramType());
          clientSessions.put(params.getClientSessionId(), session);
+         GModelState modelState = session.getInjector().getInstance(GModelState.class);
          return handleInitializeClientSessionArgs(params.getArgs());
       } catch (GLSPServerException exception) {
          throw new ResponseErrorException(
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/utils/ClientOptionsUtil.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/utils/ClientOptionsUtil.java
index 05c6deb4..9fd49381 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/utils/ClientOptionsUtil.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/utils/ClientOptionsUtil.java
@@ -27,6 +27,8 @@ public final class ClientOptionsUtil {
    public static final String SOURCE_URI = "sourceUri";
    private static final String FILE_PREFIX = "file://";
 
+   private static final String DISABLE_RELOAD = "disableReload";
+
    private ClientOptionsUtil() {}
 
    public static Optional<String> getSourceUri(final Map<String, String> options) {
@@ -35,7 +37,15 @@ public static Optional<String> getSourceUri(final Map<String, String> options) {
 
    public static Optional<String> getDiagramType(final Map<String, String> options) {
       return MapUtil.getValue(options, DIAGRAM_TYPE);
+   }
+
+   public static Optional<Boolean> getDisableReload(final Map<String, String> options) {
+      return MapUtil.getValue(options, DISABLE_RELOAD).map(Boolean::valueOf);
+   }
 
+   public static Boolean disableReloadIsTrue(final Map<String, String> options) {
+      Optional<Boolean> disableReload = getDisableReload(options);
+      return disableReload.isPresent() && disableReload.get();
    }
 
    public static Optional<File> getSourceUriAsFile(final Map<String, String> options) {
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/utils/CollaborateUtil.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/utils/CollaborateUtil.java
new file mode 100644
index 00000000..73f51d1f
--- /dev/null
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/utils/CollaborateUtil.java
@@ -0,0 +1,5 @@
+package org.eclipse.glsp.server.utils;
+
+public class CollaborateUtil {
+    public static final String FALLBACK_SUBCLIENT_ID = "FALLBACK_SUBCLIENT_ID";
+}

From 6d96d400f5a1a5ff0d607fb2fde41b1dbb25e037 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Markus=20Hegedu=CC=88s?= <markus.hegedues@prewave.ai>
Date: Mon, 8 May 2023 14:14:38 +0200
Subject: [PATCH 2/8] fix selection bug: subclientId not passed to response
 actions

---
 ...tractGModelCreateNodeOperationHandler.java |  6 +++++-
 .../GModelCreateNodeOperationHandler.java     |  6 +++++-
 .../command/DefaultCommandStackManager.java   |  4 ++--
 .../glsp/server/model/DefaultGModelState.java |  4 ----
 .../glsp/server/utils/CollaborateUtil.java    |  5 -----
 .../glsp/server/utils/CollaborationUtil.java  | 21 +++++++++++++++++++
 6 files changed, 33 insertions(+), 13 deletions(-)
 delete mode 100644 plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/utils/CollaborateUtil.java
 create mode 100644 plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/utils/CollaborationUtil.java

diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/gmodel/AbstractGModelCreateNodeOperationHandler.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/gmodel/AbstractGModelCreateNodeOperationHandler.java
index 960369e6..d7f21eb5 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/gmodel/AbstractGModelCreateNodeOperationHandler.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/gmodel/AbstractGModelCreateNodeOperationHandler.java
@@ -22,6 +22,7 @@
 import org.eclipse.glsp.graph.GModelElement;
 import org.eclipse.glsp.graph.GNode;
 import org.eclipse.glsp.graph.GPoint;
+import org.eclipse.glsp.server.actions.Action;
 import org.eclipse.glsp.server.actions.ActionDispatcher;
 import org.eclipse.glsp.server.actions.SelectAction;
 import org.eclipse.glsp.server.operations.AbstractCreateOperationHandler;
@@ -59,7 +60,10 @@ public void executeOperation(final CreateNodeOperation operation) {
          .map(location -> LayoutUtil.getRelativeLocation(location, container));
       GModelElement element = createNode(relativeLocation, operation.getArgs());
       container.getChildren().add(element);
-      actionDispatcher.dispatchAfterNextUpdate(new SelectAction(), new SelectAction(List.of(element.getId())));
+      actionDispatcher.dispatchAfterNextUpdate(
+              Action.addSubclientId(operation, new SelectAction()),
+              Action.addSubclientId(operation, new SelectAction(List.of(element.getId())))
+      );
    }
 
    /**
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/gmodel/GModelCreateNodeOperationHandler.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/gmodel/GModelCreateNodeOperationHandler.java
index b297c5bd..5f02eff8 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/gmodel/GModelCreateNodeOperationHandler.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/gmodel/GModelCreateNodeOperationHandler.java
@@ -23,6 +23,7 @@
 import org.eclipse.glsp.graph.GModelElement;
 import org.eclipse.glsp.graph.GNode;
 import org.eclipse.glsp.graph.GPoint;
+import org.eclipse.glsp.server.actions.Action;
 import org.eclipse.glsp.server.actions.ActionDispatcher;
 import org.eclipse.glsp.server.actions.SelectAction;
 import org.eclipse.glsp.server.operations.CreateEdgeOperation;
@@ -59,7 +60,10 @@ public void executeCreation(final CreateNodeOperation operation) {
       Optional<GPoint> relativeLocation = getRelativeLocation(container, absoluteLocation);
       GModelElement element = createNode(relativeLocation, operation.getArgs());
       container.getChildren().add(element);
-      actionDispatcher.dispatchAfterNextUpdate(new SelectAction(), new SelectAction(List.of(element.getId())));
+      actionDispatcher.dispatchAfterNextUpdate(
+              Action.addSubclientId(operation, new SelectAction()),
+              Action.addSubclientId(operation, new SelectAction(List.of(element.getId())))
+      );
    }
 
    protected Optional<GPoint> getLocation(final CreateNodeOperation operation) {
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/command/DefaultCommandStackManager.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/command/DefaultCommandStackManager.java
index d734100b..d0fec9a1 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/command/DefaultCommandStackManager.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/command/DefaultCommandStackManager.java
@@ -2,7 +2,7 @@
 
 import com.google.inject.Inject;
 import org.eclipse.emf.common.command.CommandStack;
-import org.eclipse.glsp.server.utils.CollaborateUtil;
+import org.eclipse.glsp.server.utils.CollaborationUtil;
 
 import java.util.ArrayList;
 import java.util.HashMap;
@@ -47,7 +47,7 @@ private String getSubclientIdOrFallback(final String subclientId) {
         if (subclientId != null) {
             return subclientId;
         }
-        return CollaborateUtil.FALLBACK_SUBCLIENT_ID;
+        return CollaborationUtil.FALLBACK_SUBCLIENT_ID;
     }
 
 }
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/model/DefaultGModelState.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/model/DefaultGModelState.java
index 5a061640..a2896720 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/model/DefaultGModelState.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/model/DefaultGModelState.java
@@ -32,10 +32,6 @@
 
 public class DefaultGModelState implements GModelState {
 
-   public DefaultGModelState() {
-      System.out.println("test");
-   }
-
    @Inject
    @ClientId
    protected String clientId;
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/utils/CollaborateUtil.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/utils/CollaborateUtil.java
deleted file mode 100644
index 73f51d1f..00000000
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/utils/CollaborateUtil.java
+++ /dev/null
@@ -1,5 +0,0 @@
-package org.eclipse.glsp.server.utils;
-
-public class CollaborateUtil {
-    public static final String FALLBACK_SUBCLIENT_ID = "FALLBACK_SUBCLIENT_ID";
-}
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/utils/CollaborationUtil.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/utils/CollaborationUtil.java
new file mode 100644
index 00000000..82989403
--- /dev/null
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/utils/CollaborationUtil.java
@@ -0,0 +1,21 @@
+/********************************************************************************
+ * Copyright (c) 2020 EclipseSource and others.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v. 2.0 which is available at
+ * https://www.eclipse.org/legal/epl-2.0.
+ *
+ * This Source Code may also be made available under the following Secondary
+ * Licenses when the conditions for such availability set forth in the Eclipse
+ * Public License v. 2.0 are satisfied: GNU General Public License, version 2
+ * with the GNU Classpath Exception which is available at
+ * https://www.gnu.org/software/classpath/license.html.
+ *
+ * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
+ ********************************************************************************/
+
+package org.eclipse.glsp.server.utils;
+
+public class CollaborationUtil {
+    public static final String FALLBACK_SUBCLIENT_ID = "FALLBACK_SUBCLIENT_ID";
+}

From cfa706509bb635ef944b74f7e850bdc5679e1700 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Markus=20Hegedu=CC=88s?= <markus.hegedues@prewave.ai>
Date: Mon, 8 May 2023 17:37:08 +0200
Subject: [PATCH 3/8] add subclientId to EmfModelState interface

---
 .../eclipse/glsp/server/emf/EMFModelState.java  |  2 +-
 .../glsp/server/emf/EMFModelStateImpl.java      | 17 +++++++++++++----
 2 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/plugins/org.eclipse.glsp.server.emf/src/org/eclipse/glsp/server/emf/EMFModelState.java b/plugins/org.eclipse.glsp.server.emf/src/org/eclipse/glsp/server/emf/EMFModelState.java
index 72b7e21f..49501a96 100644
--- a/plugins/org.eclipse.glsp.server.emf/src/org/eclipse/glsp/server/emf/EMFModelState.java
+++ b/plugins/org.eclipse.glsp.server.emf/src/org/eclipse/glsp/server/emf/EMFModelState.java
@@ -20,7 +20,7 @@
 import org.eclipse.glsp.server.model.GModelState;
 
 public interface EMFModelState extends GModelState {
-   void setEditingDomain(EditingDomain editingDomain);
+   void setEditingDomain(EditingDomain editingDomain, String subclientId);
 
    EditingDomain getEditingDomain();
 
diff --git a/plugins/org.eclipse.glsp.server.emf/src/org/eclipse/glsp/server/emf/EMFModelStateImpl.java b/plugins/org.eclipse.glsp.server.emf/src/org/eclipse/glsp/server/emf/EMFModelStateImpl.java
index 0cfb1097..de793027 100644
--- a/plugins/org.eclipse.glsp.server.emf/src/org/eclipse/glsp/server/emf/EMFModelStateImpl.java
+++ b/plugins/org.eclipse.glsp.server.emf/src/org/eclipse/glsp/server/emf/EMFModelStateImpl.java
@@ -17,6 +17,7 @@
 
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
+import org.eclipse.emf.common.command.BasicCommandStack;
 import org.eclipse.emf.common.command.CommandStack;
 import org.eclipse.emf.common.util.EList;
 import org.eclipse.emf.ecore.resource.Resource;
@@ -24,6 +25,7 @@
 import org.eclipse.emf.edit.domain.EditingDomain;
 import org.eclipse.glsp.graph.GModelIndex;
 import org.eclipse.glsp.graph.GModelRoot;
+import org.eclipse.glsp.server.internal.command.CommandStackManager;
 import org.eclipse.glsp.server.model.DefaultGModelState;
 import org.eclipse.glsp.server.session.ClientSession;
 import org.eclipse.glsp.server.session.ClientSessionListener;
@@ -50,6 +52,9 @@ public class EMFModelStateImpl extends DefaultGModelState implements EMFModelSta
    @Inject
    protected ClientSessionManager clientSessionManager;
 
+   @Inject
+   protected CommandStackManager commandStackManager;
+
    @Inject
    protected EMFIdGenerator idGenerator;
 
@@ -62,9 +67,9 @@ public void init() {
    }
 
    @Override
-   public void setEditingDomain(final EditingDomain editingDomain) {
+   public void setEditingDomain(final EditingDomain editingDomain, final String subclientId) {
       this.editingDomain = editingDomain;
-      setCommandStack(this.editingDomain.getCommandStack());
+      commandStackManager.setCommandStack(this.editingDomain.getCommandStack(), subclientId);
    }
 
    @Override
@@ -107,8 +112,12 @@ protected void closeResourceSet() {
          }
       }
       if (result) {
-         commandStack.flush();
-         saveIsDone();
+         commandStackManager.getAllCommandStack().forEach(commandStack -> {
+            commandStack.flush();
+            if (commandStack instanceof BasicCommandStack) {
+               ((BasicCommandStack) commandStack).saveIsDone();
+            }
+         });
       }
    }
 

From d835a03afa0ad0b4be3cdc2fce9c93dcbbe9bdb6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Markus=20Hegedu=CC=88s?= <markus.hegedues@prewave.ai>
Date: Mon, 8 May 2023 17:54:59 +0200
Subject: [PATCH 4/8] move CommandStackManager out of internal

---
 .../src/org/eclipse/glsp/server/emf/EMFModelStateImpl.java  | 2 +-
 .../server/{internal => }/command/CommandStackFactory.java  | 2 +-
 .../server/{internal => }/command/CommandStackManager.java  | 2 +-
 .../{internal => }/command/DefaultCommandStackManager.java  | 2 +-
 .../src/org/eclipse/glsp/server/di/DiagramModule.java       | 6 +++---
 .../gmodel/commandstack/GModelCommandStackFactory.java      | 2 +-
 .../org/eclipse/glsp/server/model/DefaultGModelState.java   | 2 +-
 7 files changed, 9 insertions(+), 9 deletions(-)
 rename plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/{internal => }/command/CommandStackFactory.java (72%)
 rename plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/{internal => }/command/CommandStackManager.java (85%)
 rename plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/{internal => }/command/DefaultCommandStackManager.java (97%)

diff --git a/plugins/org.eclipse.glsp.server.emf/src/org/eclipse/glsp/server/emf/EMFModelStateImpl.java b/plugins/org.eclipse.glsp.server.emf/src/org/eclipse/glsp/server/emf/EMFModelStateImpl.java
index de793027..1296c129 100644
--- a/plugins/org.eclipse.glsp.server.emf/src/org/eclipse/glsp/server/emf/EMFModelStateImpl.java
+++ b/plugins/org.eclipse.glsp.server.emf/src/org/eclipse/glsp/server/emf/EMFModelStateImpl.java
@@ -25,7 +25,7 @@
 import org.eclipse.emf.edit.domain.EditingDomain;
 import org.eclipse.glsp.graph.GModelIndex;
 import org.eclipse.glsp.graph.GModelRoot;
-import org.eclipse.glsp.server.internal.command.CommandStackManager;
+import org.eclipse.glsp.server.command.CommandStackManager;
 import org.eclipse.glsp.server.model.DefaultGModelState;
 import org.eclipse.glsp.server.session.ClientSession;
 import org.eclipse.glsp.server.session.ClientSessionListener;
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/command/CommandStackFactory.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/command/CommandStackFactory.java
similarity index 72%
rename from plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/command/CommandStackFactory.java
rename to plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/command/CommandStackFactory.java
index 9fa927ad..9068ba62 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/command/CommandStackFactory.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/command/CommandStackFactory.java
@@ -1,4 +1,4 @@
-package org.eclipse.glsp.server.internal.command;
+package org.eclipse.glsp.server.command;
 
 import org.eclipse.emf.common.command.CommandStack;
 
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/command/CommandStackManager.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/command/CommandStackManager.java
similarity index 85%
rename from plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/command/CommandStackManager.java
rename to plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/command/CommandStackManager.java
index bc9f8fa2..bced2277 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/command/CommandStackManager.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/command/CommandStackManager.java
@@ -1,4 +1,4 @@
-package org.eclipse.glsp.server.internal.command;
+package org.eclipse.glsp.server.command;
 
 import org.eclipse.emf.common.command.CommandStack;
 
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/command/DefaultCommandStackManager.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/command/DefaultCommandStackManager.java
similarity index 97%
rename from plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/command/DefaultCommandStackManager.java
rename to plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/command/DefaultCommandStackManager.java
index d0fec9a1..ab774af9 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/command/DefaultCommandStackManager.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/command/DefaultCommandStackManager.java
@@ -1,4 +1,4 @@
-package org.eclipse.glsp.server.internal.command;
+package org.eclipse.glsp.server.command;
 
 import com.google.inject.Inject;
 import org.eclipse.emf.common.command.CommandStack;
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/di/DiagramModule.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/di/DiagramModule.java
index 00787b4f..d08fb71b 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/di/DiagramModule.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/di/DiagramModule.java
@@ -87,9 +87,9 @@
 import org.eclipse.glsp.server.gson.GraphGsonConfigurationFactory;
 import org.eclipse.glsp.server.internal.actions.DefaultActionDispatcher;
 import org.eclipse.glsp.server.internal.actions.DefaultActionHandlerRegistry;
-import org.eclipse.glsp.server.internal.command.CommandStackFactory;
-import org.eclipse.glsp.server.internal.command.CommandStackManager;
-import org.eclipse.glsp.server.internal.command.DefaultCommandStackManager;
+import org.eclipse.glsp.server.command.CommandStackFactory;
+import org.eclipse.glsp.server.command.CommandStackManager;
+import org.eclipse.glsp.server.command.DefaultCommandStackManager;
 import org.eclipse.glsp.server.internal.diagram.DefaultServerConfigurationContribution;
 import org.eclipse.glsp.server.internal.featues.directediting.DefaultContextEditValidatorRegistry;
 import org.eclipse.glsp.server.internal.featues.navigation.DefaultNavigationTargetProviderRegistry;
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/gmodel/commandstack/GModelCommandStackFactory.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/gmodel/commandstack/GModelCommandStackFactory.java
index 4b280354..70fa53fe 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/gmodel/commandstack/GModelCommandStackFactory.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/gmodel/commandstack/GModelCommandStackFactory.java
@@ -1,7 +1,7 @@
 package org.eclipse.glsp.server.internal.gmodel.commandstack;
 
 import org.eclipse.emf.common.command.CommandStack;
-import org.eclipse.glsp.server.internal.command.CommandStackFactory;
+import org.eclipse.glsp.server.command.CommandStackFactory;
 
 public class GModelCommandStackFactory implements CommandStackFactory  {
     @Override
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/model/DefaultGModelState.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/model/DefaultGModelState.java
index 5e1873d6..93409511 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/model/DefaultGModelState.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/model/DefaultGModelState.java
@@ -25,7 +25,7 @@
 import org.eclipse.glsp.graph.GModelIndex;
 import org.eclipse.glsp.graph.GModelRoot;
 import org.eclipse.glsp.server.di.ClientId;
-import org.eclipse.glsp.server.internal.command.CommandStackManager;
+import org.eclipse.glsp.server.command.CommandStackManager;
 import org.eclipse.glsp.server.internal.gmodel.commandstack.GModelCommandStack;
 
 import com.google.inject.Inject;

From 19a4bfd82653bfdeace3bfc0f499aeaf2125fd4c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Markus=20Hegedu=CC=88s?= <markus.hegedues@prewave.ai>
Date: Wed, 10 May 2023 01:01:15 +0200
Subject: [PATCH 5/8] give access to command package from outside

---
 plugins/org.eclipse.glsp.server/META-INF/MANIFEST.MF | 1 +
 1 file changed, 1 insertion(+)

diff --git a/plugins/org.eclipse.glsp.server/META-INF/MANIFEST.MF b/plugins/org.eclipse.glsp.server/META-INF/MANIFEST.MF
index f2de91a4..7203ce44 100644
--- a/plugins/org.eclipse.glsp.server/META-INF/MANIFEST.MF
+++ b/plugins/org.eclipse.glsp.server/META-INF/MANIFEST.MF
@@ -32,6 +32,7 @@ Export-Package: org.eclipse.glsp.server.actions,
  org.eclipse.glsp.server.features.validation,
  org.eclipse.glsp.server.gmodel,
  org.eclipse.glsp.server.gson,
+ org.eclipse.glsp.server.command,
  org.eclipse.glsp.server.internal.actions;x-internal:=true,
  org.eclipse.glsp.server.internal.di.scope;x-internal:=true,
  org.eclipse.glsp.server.internal.diagram;x-internal:=true,

From 78a5fbdfb54492c92b46dfd067b91afcd131da6d Mon Sep 17 00:00:00 2001
From: Olaf Lessenich <olessenich@eclipsesource.com>
Date: Wed, 3 May 2023 13:49:21 +0200
Subject: [PATCH 6/8] fix findings

---
 .../src/org/eclipse/glsp/server/emf/EMFModelStateImpl.java    | 2 +-
 .../org/eclipse/glsp/server/command/CommandStackManager.java  | 2 +-
 .../glsp/server/command/DefaultCommandStackManager.java       | 4 ++--
 .../org/eclipse/glsp/server/protocol/DefaultGLSPServer.java   | 2 --
 4 files changed, 4 insertions(+), 6 deletions(-)

diff --git a/plugins/org.eclipse.glsp.server.emf/src/org/eclipse/glsp/server/emf/EMFModelStateImpl.java b/plugins/org.eclipse.glsp.server.emf/src/org/eclipse/glsp/server/emf/EMFModelStateImpl.java
index 1296c129..d88a1f4b 100644
--- a/plugins/org.eclipse.glsp.server.emf/src/org/eclipse/glsp/server/emf/EMFModelStateImpl.java
+++ b/plugins/org.eclipse.glsp.server.emf/src/org/eclipse/glsp/server/emf/EMFModelStateImpl.java
@@ -112,7 +112,7 @@ protected void closeResourceSet() {
          }
       }
       if (result) {
-         commandStackManager.getAllCommandStack().forEach(commandStack -> {
+         commandStackManager.getAllCommandStacks().forEach(commandStack -> {
             commandStack.flush();
             if (commandStack instanceof BasicCommandStack) {
                ((BasicCommandStack) commandStack).saveIsDone();
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/command/CommandStackManager.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/command/CommandStackManager.java
index bced2277..2d810828 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/command/CommandStackManager.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/command/CommandStackManager.java
@@ -7,7 +7,7 @@
 public interface CommandStackManager {
     CommandStack getOrCreateCommandStack(String subclientId);
 
-    List<CommandStack> getAllCommandStack();
+    List<CommandStack> getAllCommandStacks();
 
     void setCommandStack(CommandStack commandStack, String subclientId);
 }
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/command/DefaultCommandStackManager.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/command/DefaultCommandStackManager.java
index ab774af9..53c64ded 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/command/DefaultCommandStackManager.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/command/DefaultCommandStackManager.java
@@ -21,7 +21,7 @@ public class DefaultCommandStackManager implements CommandStackManager {
     public CommandStack getOrCreateCommandStack(final String subclientId) {
         String subclientIdOrFallback = getSubclientIdOrFallback(subclientId);
         if (commandStackMap.containsKey(subclientIdOrFallback)) {
-            return commandStackMap.get(getSubclientIdOrFallback(subclientIdOrFallback));
+            return commandStackMap.get(subclientIdOrFallback);
         }
 
         CommandStack commandStack = factory.createCommandStack();
@@ -30,7 +30,7 @@ public CommandStack getOrCreateCommandStack(final String subclientId) {
     }
 
     @Override
-    public List<CommandStack> getAllCommandStack() {
+    public List<CommandStack> getAllCommandStacks() {
         return new ArrayList<>(commandStackMap.values());
     }
 
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/protocol/DefaultGLSPServer.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/protocol/DefaultGLSPServer.java
index 3fa50fd7..5903d988 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/protocol/DefaultGLSPServer.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/protocol/DefaultGLSPServer.java
@@ -28,7 +28,6 @@
 import org.apache.logging.log4j.Logger;
 import org.eclipse.glsp.server.actions.ActionMessage;
 import org.eclipse.glsp.server.actions.ActionRegistry;
-import org.eclipse.glsp.server.model.GModelState;
 import org.eclipse.glsp.server.session.ClientSession;
 import org.eclipse.glsp.server.session.ClientSessionManager;
 import org.eclipse.glsp.server.types.GLSPServerException;
@@ -121,7 +120,6 @@ public CompletableFuture<Void> initializeClientSession(final InitializeClientSes
          ClientSession session = sessionManager.getOrCreateClientSession(params.getClientSessionId(),
             params.getDiagramType());
          clientSessions.put(params.getClientSessionId(), session);
-         GModelState modelState = session.getInjector().getInstance(GModelState.class);
          return handleInitializeClientSessionArgs(params.getArgs());
       } catch (GLSPServerException exception) {
          throw new ResponseErrorException(

From 3d8d7f4fc02a74c42649f5f5a6a013be7f31f6c0 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Markus=20Hegedu=CC=88s?= <markus.hegedues@prewave.ai>
Date: Thu, 1 Feb 2024 19:49:59 +0100
Subject: [PATCH 7/8] Add comment to subclientId, fix remaining findings from
 Merge

---
 .../src/org/eclipse/glsp/server/actions/Action.java        | 7 ++++---
 .../server/features/core/model/ModelSubmissionHandler.java | 2 +-
 .../features/core/model/RequestModelActionHandler.java     | 3 ---
 .../server/gmodel/GModelCreateNodeOperationHandler.java    | 7 ++++---
 4 files changed, 9 insertions(+), 10 deletions(-)

diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/actions/Action.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/actions/Action.java
index e7387a6d..1ea32038 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/actions/Action.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/actions/Action.java
@@ -16,7 +16,6 @@
 package org.eclipse.glsp.server.actions;
 
 import org.eclipse.glsp.server.protocol.GLSPServer;
-import org.eclipse.glsp.server.internal.util.GenericsUtil;
 
 /**
  * Java-implementation of the `Action` interface. An action is a declarative description of a behavior that
@@ -41,10 +40,12 @@ public abstract class Action {
     */
    private boolean receivedFromClient;
 
+   /**
+    * Unique identifier specifying the initiator of the action in a collaboration session.
+    * This value is initialized on the initating client.
+    */
    private String subclientId;
 
-   public Action(final String kind) {
-
    public Action(final String kind, final String subclientId) {
       super();
       this.kind = kind;
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/features/core/model/ModelSubmissionHandler.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/features/core/model/ModelSubmissionHandler.java
index 87b8f830..e7ebbbb4 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/features/core/model/ModelSubmissionHandler.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/features/core/model/ModelSubmissionHandler.java
@@ -88,7 +88,7 @@ public List<Action> submitInitialModel(final RequestModelAction requestAction) {
        * Therefore we temporarily store the action later retrival
        */
       this.requestModelAction = Optional.of(requestAction);
-      return submitModel();
+      return submitModel(requestAction.getSubclientId());
 
    }
 
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/features/core/model/RequestModelActionHandler.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/features/core/model/RequestModelActionHandler.java
index e71614a0..6d9d0ad1 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/features/core/model/RequestModelActionHandler.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/features/core/model/RequestModelActionHandler.java
@@ -29,9 +29,6 @@
 import org.eclipse.glsp.server.model.GModelState;
 import org.eclipse.glsp.server.utils.ClientOptionsUtil;
 import org.eclipse.glsp.server.utils.StatusActionUtil;
-import org.eclipse.glsp.server.utils.ClientOptionsUtil;
-import org.eclipse.glsp.server.utils.ServerMessageUtil;
-import org.eclipse.glsp.server.utils.ServerStatusUtil;
 
 import com.google.inject.Inject;
 
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/gmodel/GModelCreateNodeOperationHandler.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/gmodel/GModelCreateNodeOperationHandler.java
index 6b701699..e3921114 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/gmodel/GModelCreateNodeOperationHandler.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/gmodel/GModelCreateNodeOperationHandler.java
@@ -64,10 +64,11 @@ public void executeCreation(final CreateNodeOperation operation) {
       Optional<GPoint> relativeLocation = getRelativeLocation(container, absoluteLocation);
       GModelElement element = createNode(relativeLocation, operation.getArgs());
       container.getChildren().add(element);
-      actionDispatcher.dispatchAfterNextUpdate(SelectAction.addSelection(List.of(element.getId())));
       actionDispatcher.dispatchAfterNextUpdate(
-              Action.addSubclientId(operation, new SelectAction()),
-              Action.addSubclientId(operation, new SelectAction(List.of(element.getId())))
+              Action.addSubclientId(
+                      operation,
+                      SelectAction.addSelection(List.of(element.getId()))
+              )
       );
    }
 

From b214e079a3339bb7a44f89cc59fef591876af603 Mon Sep 17 00:00:00 2001
From: MatthiasHofstaetter <matthias.hofstaetter94@gmailc.om>
Date: Fri, 9 Aug 2024 17:10:56 +0200
Subject: [PATCH 8/8] * set subclientid within ActionDispatcher to remove it
 from method signatures

---
 .../actions/SaveModelActionHandler.java       |  5 ++-
 .../model/ComputedBoundsActionHandler.java    |  2 +-
 .../core/model/ModelSubmissionHandler.java    | 18 ++++-----
 .../undoredo/UndoRedoActionHandler.java       | 12 +++---
 .../actions/DefaultActionDispatcher.java      |  7 ++++
 .../glsp/server/model/DefaultGModelState.java | 37 +++++++++++--------
 .../glsp/server/model/GModelState.java        |  6 ++-
 .../eclipse/glsp/server/model/ModelState.java | 10 ++---
 .../operations/OperationActionHandler.java    | 12 +++---
 9 files changed, 63 insertions(+), 46 deletions(-)

diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/actions/SaveModelActionHandler.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/actions/SaveModelActionHandler.java
index 44c72bdf..18fd9952 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/actions/SaveModelActionHandler.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/actions/SaveModelActionHandler.java
@@ -45,11 +45,12 @@ public List<Action> executeAction(final SaveModelAction action) {
       modelSourceWatcher.ifPresent(watcher -> watcher.pauseWatching());
       try {
          sourceModelStorage.saveSourceModel(action);
-         modelState.saveIsDone(action.getSubclientId());
+         modelState.saveIsDone();
       } finally {
          modelSourceWatcher.ifPresent(watcher -> watcher.continueWatching());
       }
-      return listOf(new SetDirtyStateAction(modelState.isDirty(action.getSubclientId()), SetDirtyStateAction.Reason.SAVE));
+      return listOf(
+         new SetDirtyStateAction(modelState.isDirty(), SetDirtyStateAction.Reason.SAVE));
    }
 
 }
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/features/core/model/ComputedBoundsActionHandler.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/features/core/model/ComputedBoundsActionHandler.java
index 8c58d234..d4be507d 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/features/core/model/ComputedBoundsActionHandler.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/features/core/model/ComputedBoundsActionHandler.java
@@ -45,7 +45,7 @@ public List<Action> executeAction(final ComputedBoundsAction action) {
          if (model != null && action.getRevision().isPresent()
             && action.getRevision().get().doubleValue() == model.getRevision()) {
             LayoutUtil.applyBounds(model, action, modelState);
-            return submissionHandler.submitModelDirectly(action.getSubclientId());
+            return submissionHandler.submitModelDirectly();
          }
       }
       return none();
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/features/core/model/ModelSubmissionHandler.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/features/core/model/ModelSubmissionHandler.java
index e7ebbbb4..8e15a563 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/features/core/model/ModelSubmissionHandler.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/features/core/model/ModelSubmissionHandler.java
@@ -103,7 +103,7 @@ public List<Action> submitInitialModel(final RequestModelAction requestAction) {
     * @param reason The optional reason that caused the model update.
     * @return A list of actions to be processed in order to submit the model.
     */
-   public List<Action> submitModel(final String reason, final String subclientId) {
+   public List<Action> submitModel(final String reason) {
       modelFactory.createGModel();
       int revision = this.requestModelAction.isPresent() ? 0 : this.modelState.getRoot().getRevision() + 1;
       modelState.getRoot().setRevision(revision);
@@ -112,14 +112,14 @@ public List<Action> submitModel(final String reason, final String subclientId) {
       if (needsClientLayout) {
          synchronized (modelLock) {
             return Arrays.asList(new RequestBoundsAction(modelState.getRoot()),
-               new SetDirtyStateAction(modelState.isDirty(subclientId), reason));
+               new SetDirtyStateAction(modelState.isDirty(), reason));
          }
       }
-      return submitModelDirectly(reason, subclientId);
+      return submitModelDirectly(reason);
    }
 
-   public List<Action> submitModel(final String subclientId) {
-      return submitModel(null, subclientId);
+   public List<Action> submitModel() {
+      return submitModel(null);
    }
 
    /**
@@ -139,7 +139,7 @@ public List<Action> submitModel(final String subclientId) {
     * @param reason The optional reason that caused the model update.
     * @return A list of actions to be processed in order to submit the model.
     */
-   public List<Action> submitModelDirectly(final String reason, final String subclientId) {
+   public List<Action> submitModelDirectly(final String reason) {
       GModelRoot gModel = modelState.getRoot();
       if (diagramConfiguration.getLayoutKind() == ServerLayoutKind.AUTOMATIC && layoutEngine.isPresent()) {
          layoutEngine.get().layout();
@@ -152,7 +152,7 @@ public List<Action> submitModelDirectly(final String reason, final String subcli
          List<Action> result = new ArrayList<>();
          result.add(modelAction);
          if (!diagramConfiguration.needsClientLayout()) {
-            result.add(new SetDirtyStateAction(modelState.isDirty(subclientId), reason));
+            result.add(new SetDirtyStateAction(modelState.isDirty(), reason));
          }
          if (validator.isPresent()) {
             List<Marker> markers = validator.get() //
@@ -163,8 +163,8 @@ public List<Action> submitModelDirectly(final String reason, final String subcli
       }
    }
 
-   public List<Action> submitModelDirectly(final String subclientId) {
-      return submitModelDirectly(null, subclientId);
+   public List<Action> submitModelDirectly() {
+      return submitModelDirectly(null);
    }
 
    protected SetModelAction createSetModeAction(final GModelRoot newRoot) {
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/features/undoredo/UndoRedoActionHandler.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/features/undoredo/UndoRedoActionHandler.java
index ddb94d75..fd203908 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/features/undoredo/UndoRedoActionHandler.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/features/undoredo/UndoRedoActionHandler.java
@@ -39,12 +39,12 @@ public class UndoRedoActionHandler implements ActionHandler {
 
    @Override
    public List<Action> execute(final Action action) {
-      if (action instanceof UndoAction && modelState.canUndo(action.getSubclientId())) {
-         modelState.undo(action.getSubclientId());
-         return modelSubmissionHandler.submitModel(SetDirtyStateAction.Reason.UNDO, action.getSubclientId());
-      } else if (action instanceof RedoAction && modelState.canRedo(action.getSubclientId())) {
-         modelState.redo(action.getSubclientId());
-         return modelSubmissionHandler.submitModel(SetDirtyStateAction.Reason.REDO, action.getSubclientId());
+      if (action instanceof UndoAction && modelState.canUndo()) {
+         modelState.undo();
+         return modelSubmissionHandler.submitModel(SetDirtyStateAction.Reason.UNDO);
+      } else if (action instanceof RedoAction && modelState.canRedo()) {
+         modelState.redo();
+         return modelSubmissionHandler.submitModel(SetDirtyStateAction.Reason.REDO);
       }
       LOGGER.warn("Cannot undo or redo");
       return none();
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/actions/DefaultActionDispatcher.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/actions/DefaultActionDispatcher.java
index f89f6099..bbeb989e 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/actions/DefaultActionDispatcher.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/internal/actions/DefaultActionDispatcher.java
@@ -39,6 +39,7 @@
 import org.eclipse.glsp.server.di.ClientId;
 import org.eclipse.glsp.server.disposable.Disposable;
 import org.eclipse.glsp.server.features.core.model.UpdateModelAction;
+import org.eclipse.glsp.server.model.GModelState;
 import org.eclipse.glsp.server.protocol.GLSPClient;
 import org.eclipse.glsp.server.utils.FutureUtil;
 
@@ -85,6 +86,10 @@ public class DefaultActionDispatcher extends Disposable implements ActionDispatc
    @Inject
    protected Provider<GLSPClient> client;
 
+   // use modelstate here to set subclient id
+   @Inject
+   protected GModelState modelState;
+
    public DefaultActionDispatcher() {
       this.name = getClass().getSimpleName() + " " + COUNT.incrementAndGet();
       this.thread = new Thread(this::runThread);
@@ -193,6 +198,8 @@ protected List<CompletableFuture<Void>> runAction(final Action action) {
          throw new IllegalArgumentException("No handler registered for action: " + action);
       }
 
+      this.modelState.setParticipationID(action.getSubclientId());
+
       List<CompletableFuture<Void>> results = new ArrayList<>();
       for (final ActionHandler actionHandler : actionHandlers) {
          final List<Action> responses = actionHandler.execute(action).stream()
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/model/DefaultGModelState.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/model/DefaultGModelState.java
index 93409511..7144bdae 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/model/DefaultGModelState.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/model/DefaultGModelState.java
@@ -24,8 +24,8 @@
 import org.eclipse.emf.common.command.CommandStack;
 import org.eclipse.glsp.graph.GModelIndex;
 import org.eclipse.glsp.graph.GModelRoot;
-import org.eclipse.glsp.server.di.ClientId;
 import org.eclipse.glsp.server.command.CommandStackManager;
+import org.eclipse.glsp.server.di.ClientId;
 import org.eclipse.glsp.server.internal.gmodel.commandstack.GModelCommandStack;
 
 import com.google.inject.Inject;
@@ -46,6 +46,7 @@ public class DefaultGModelState implements GModelState {
    protected GModelRoot currentModel;
    protected String editMode;
    protected GModelIndex index = GModelIndex.empty();
+   protected String participationId;
 
    @Inject
    public void init() {
@@ -83,50 +84,50 @@ protected GModelIndex getOrUpdateIndex(final GModelRoot newRoot) {
    public GModelIndex getIndex() { return index; }
 
    @Override
-   public void execute(final Command command, String subclientId) {
-      CommandStack commandStack = commandStackManager.getOrCreateCommandStack(subclientId);
+   public void execute(final Command command) {
+      CommandStack commandStack = commandStackManager.getOrCreateCommandStack(this.participationId);
       if (commandStack != null) {
          commandStack.execute(command);
       }
    }
 
    @Override
-   public boolean canUndo(final String subclientId) {
-      CommandStack commandStack = commandStackManager.getOrCreateCommandStack(subclientId);
+   public boolean canUndo() {
+      CommandStack commandStack = commandStackManager.getOrCreateCommandStack(this.participationId);
       return commandStack != null && commandStack.canUndo();
    }
 
    @Override
-   public boolean canRedo(final String subclientId) {
-      CommandStack commandStack = commandStackManager.getOrCreateCommandStack(subclientId);
+   public boolean canRedo() {
+      CommandStack commandStack = commandStackManager.getOrCreateCommandStack(this.participationId);
       return commandStack != null && commandStack.canRedo();
    }
 
    @Override
-   public void undo(final String subclientId) {
-      CommandStack commandStack = commandStackManager.getOrCreateCommandStack(subclientId);
+   public void undo() {
+      CommandStack commandStack = commandStackManager.getOrCreateCommandStack(this.participationId);
       if (commandStack != null) {
          commandStack.undo();
       }
    }
 
    @Override
-   public void redo(final String subclientId) {
-      CommandStack commandStack = commandStackManager.getOrCreateCommandStack(subclientId);
+   public void redo() {
+      CommandStack commandStack = commandStackManager.getOrCreateCommandStack(this.participationId);
       if (commandStack != null) {
          commandStack.redo();
       }
    }
 
    @Override
-   public boolean isDirty(final String subclientId) {
-      CommandStack commandStack = commandStackManager.getOrCreateCommandStack(subclientId);
+   public boolean isDirty() {
+      CommandStack commandStack = commandStackManager.getOrCreateCommandStack(this.participationId);
       return commandStack instanceof BasicCommandStack && ((BasicCommandStack) commandStack).isSaveNeeded();
    }
 
    @Override
-   public void saveIsDone(final String subclientId) {
-      CommandStack commandStack = commandStackManager.getOrCreateCommandStack(subclientId);
+   public void saveIsDone() {
+      CommandStack commandStack = commandStackManager.getOrCreateCommandStack(this.participationId);
       if (commandStack instanceof BasicCommandStack) {
          ((BasicCommandStack) commandStack).saveIsDone();
       }
@@ -153,4 +154,10 @@ public <P> Optional<P> getProperty(final String key, final Class<P> type) {
    public void clearProperty(final String key) {
       properties.remove(key);
    }
+
+   @Override
+   public void setParticipationID(final String id) {
+      this.participationId = id;
+
+   }
 }
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/model/GModelState.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/model/GModelState.java
index 70ffa118..c147ba73 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/model/GModelState.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/model/GModelState.java
@@ -36,12 +36,14 @@ public interface GModelState extends ModelState<GModelRoot> {
    /**
     * Called after a save has been successfully performed.
     */
-   void saveIsDone(String subclientId);
+   void saveIsDone();
 
    /**
     * Uses its {@link BasicCommandStack} to execute a given {@link Command}.
     *
     * @param command The {@link Command} to be executed.
     */
-   void execute(Command command, String subclientId);
+   void execute(Command command);
+
+   void setParticipationID(String id);
 }
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/model/ModelState.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/model/ModelState.java
index 731dcc79..0a9598ff 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/model/ModelState.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/model/ModelState.java
@@ -34,15 +34,15 @@ interface ModelState<T> {
 
    void updateRoot(T newRoot);
 
-   boolean canUndo(String subclientId);
+   boolean canUndo();
 
-   boolean canRedo(String subclientId);
+   boolean canRedo();
 
-   void undo(String subclientId);
+   void undo();
 
-   void redo(String subclientId);
+   void redo();
 
-   boolean isDirty(String subclientId);
+   boolean isDirty();
 
    String getEditMode();
 
diff --git a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/operations/OperationActionHandler.java b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/operations/OperationActionHandler.java
index 1fa35e44..82a12d80 100644
--- a/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/operations/OperationActionHandler.java
+++ b/plugins/org.eclipse.glsp.server/src/org/eclipse/glsp/server/operations/OperationActionHandler.java
@@ -62,18 +62,18 @@ protected List<Action> executeOperation(final Operation operation) {
    protected List<Action> executeHandler(final Operation operation, final OperationHandler<?> handler) {
       Optional<Command> command = handler.execute(operation);
       if (command.isPresent()) {
-         exexcuteCommand(command.get(), operation.getSubclientId());
-         return submitModel(operation.getSubclientId());
+         exexcuteCommand(command.get());
+         return submitModel();
       }
       return none();
    }
 
-   protected void exexcuteCommand(final Command command, final String subclientId) {
-      modelState.execute(command, subclientId);
+   protected void exexcuteCommand(final Command command) {
+      modelState.execute(command);
    }
 
-   protected List<Action> submitModel(final String subclientId) {
-      return modelSubmissionHandler.submitModel(SetDirtyStateAction.Reason.OPERATION, subclientId);
+   protected List<Action> submitModel() {
+      return modelSubmissionHandler.submitModel(SetDirtyStateAction.Reason.OPERATION);
    }
 
    /**