[GEF] Use EditPartViewer where possible

The IEditPartViewer and the EditPartViewer interfaces have been aligned
close enough so that in several places, we can work directly on the GEF
interface.

Author: ptziegler

org.eclipse.wb.core.java/src/org/eclipse/wb/internal/core/editor/DesignContextMenuProvider.java

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2011, 2024 Google, Inc and others
+ * Copyright (c) 2011, 2026 Google, Inc and others
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License 2.0 which is available at
@@ -16,7 +16,6 @@
 import org.eclipse.wb.core.editor.IContextMenuConstants;
 import org.eclipse.wb.core.editor.constants.IEditorPreferenceConstants;
 import org.eclipse.wb.core.model.ObjectInfo;
-import org.eclipse.wb.gef.core.IEditPartViewer;
 import org.eclipse.wb.internal.core.editor.actions.DesignPageActions;
 import org.eclipse.wb.internal.core.utils.execution.ExecutionUtils;
 import org.eclipse.wb.internal.core.utils.execution.RunnableEx;
@@ -25,6 +24,7 @@
 
 import org.eclipse.core.runtime.preferences.InstanceScope;
 import org.eclipse.gef.EditPart;
+import org.eclipse.gef.EditPartViewer;
 import org.eclipse.jface.action.IMenuManager;
 import org.eclipse.jface.action.Separator;
 
@@ -72,7 +72,7 @@ public static void addGroups(IMenuManager manager) {
 	// Constructor
 	//
 	////////////////////////////////////////////////////////////////////////////
-	public DesignContextMenuProvider(IEditPartViewer viewer, DesignPageActions pageActions) {
+	public DesignContextMenuProvider(EditPartViewer viewer, DesignPageActions pageActions) {
 		super(viewer);
 		m_pageActions = pageActions;
 	}

org.eclipse.wb.core.java/src/org/eclipse/wb/internal/core/editor/JavaDesignToolbarHelper.java

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2011 Google, Inc.
+ * Copyright (c) 2011, 2026 Google, Inc. and others.
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License 2.0 which is available at
@@ -14,10 +14,10 @@
 
 import org.eclipse.wb.core.model.JavaInfo;
 import org.eclipse.wb.core.model.ObjectInfo;
-import org.eclipse.wb.gef.core.IEditPartViewer;
 import org.eclipse.wb.internal.core.editor.actions.DesignPageActions;
 import org.eclipse.wb.internal.core.nls.ExternalizeStringsContributionItem;
 
+import org.eclipse.gef.EditPartViewer;
 import org.eclipse.jface.action.Separator;
 import org.eclipse.jface.action.ToolBarManager;
 import org.eclipse.swt.widgets.ToolBar;
@@ -48,9 +48,9 @@ public JavaDesignToolbarHelper(ToolBar toolBar) {
 	//
 	////////////////////////////////////////////////////////////////////////////
 	/**
-	 * Initializes with {@link DesignPageActions} and {@link IEditPartViewer}.
+	 * Initializes with {@link DesignPageActions} and {@link EditPartViewer}.
 	 */
-	public void initialize(DesignPageActions pageActions, IEditPartViewer viewer) {
+	public void initialize(DesignPageActions pageActions, EditPartViewer viewer) {
 		super.initialize(viewer);
 		m_pageActions = pageActions;
 	}

org.eclipse.wb.core.java/src/org/eclipse/wb/internal/core/editor/actions/DesignPageActions.java

@@ -13,7 +13,6 @@
 package org.eclipse.wb.internal.core.editor.actions;
 
 import org.eclipse.wb.core.model.JavaInfo;
-import org.eclipse.wb.gef.core.IEditPartViewer;
 import org.eclipse.wb.internal.core.editor.DesignPage;
 import org.eclipse.wb.internal.core.editor.actions.assistant.LayoutAssistantAction;
 import org.eclipse.wb.internal.core.editor.actions.errors.ErrorsAction;
@@ -60,7 +59,7 @@ public final class DesignPageActions {
 	 * Initializes new {@link DesignPageActions}.
 	 *
 	 * @param viewer
-	 *          the {@link IEditPartViewer} of {@link DesignPage}.
+	 *          the {@link EditPartViewer} of {@link DesignPage}.
 	 * @param actionBars
 	 *          the editor site {@link IActionBars}.
 	 */

org.eclipse.wb.core/src-gef/org/eclipse/wb/gef/core/tools/CreationTool.java

@@ -12,11 +12,11 @@
  *******************************************************************************/
 package org.eclipse.wb.gef.core.tools;
 
-import org.eclipse.wb.gef.core.IEditPartViewer;
 import org.eclipse.wb.gef.core.requests.CreateRequest;
 import org.eclipse.wb.gef.core.requests.ICreationFactory;
 
 import org.eclipse.gef.EditPart;
+import org.eclipse.gef.EditPartViewer;
 import org.eclipse.gef.Request;
 
 /**
@@ -85,7 +85,7 @@ protected void selectAddedObjects() {
 		CreateRequest request = (CreateRequest) getTargetRequest();
 		Object model = request.getSelectObject();
 		if (model != null) {
-			IEditPartViewer viewer = getCurrentViewer();
+			EditPartViewer viewer = getCurrentViewer();
 			if (viewer != null) {
 				EditPart editPart = viewer.getEditPartRegistry().get(model);
 				if (editPart != null) {

org.eclipse.wb.core/src-gef/org/eclipse/wb/gef/core/tools/DragEditPartTracker.java

@@ -12,7 +12,6 @@
  *******************************************************************************/
 package org.eclipse.wb.gef.core.tools;
 
-import org.eclipse.wb.gef.core.IEditPartViewer;
 import org.eclipse.wb.gef.core.requests.ChangeBoundsRequest;
 import org.eclipse.wb.gef.core.requests.DragPermissionRequest;
 import org.eclipse.wb.gef.graphical.GraphicalEditPart;
@@ -22,6 +21,7 @@
 import org.eclipse.draw2d.IFigure;
 import org.eclipse.draw2d.geometry.Point;
 import org.eclipse.gef.EditPart;
+import org.eclipse.gef.EditPartViewer;
 import org.eclipse.gef.EditPartViewer.Conditional;
 import org.eclipse.gef.Request;
 import org.eclipse.gef.RequestConstants;
@@ -255,7 +255,7 @@ private List<Object> getOperationSetModels() {
 	 */
 	private void restoreSelectionFromModels(List<Object> models) {
 		if (models != null) {
-			IEditPartViewer viewer = getCurrentViewer();
+			EditPartViewer viewer = getCurrentViewer();
 			// prepare new EditPart's
 			List<EditPart> newEditParts = new ArrayList<>();
 			for (Object model : models) {

org.eclipse.wb.core/src-gef/org/eclipse/wb/gef/core/tools/PasteTool.java

@@ -12,10 +12,10 @@
  *******************************************************************************/
 package org.eclipse.wb.gef.core.tools;
 
-import org.eclipse.wb.gef.core.IEditPartViewer;
 import org.eclipse.wb.gef.core.requests.PasteRequest;
 
 import org.eclipse.gef.EditPart;
+import org.eclipse.gef.EditPartViewer;
 import org.eclipse.gef.Request;
 import org.eclipse.jface.viewers.StructuredSelection;
 
@@ -68,7 +68,7 @@ protected Request createTargetRequest() {
 
 	@Override
 	protected void selectAddedObjects() {
-		final IEditPartViewer viewer = getCurrentViewer();
+		final EditPartViewer viewer = getCurrentViewer();
 		// prepare pasted EditPart's
 		List<EditPart> editParts = new ArrayList<>();
 		{

org.eclipse.wb.core/src-gef/org/eclipse/wb/gef/core/tools/SelectEditPartTracker.java

@@ -12,9 +12,8 @@
  *******************************************************************************/
 package org.eclipse.wb.gef.core.tools;
 
-import org.eclipse.wb.gef.core.IEditPartViewer;
-
 import org.eclipse.gef.EditPart;
+import org.eclipse.gef.EditPartViewer;
 import org.eclipse.gef.RequestConstants;
 import org.eclipse.gef.requests.SelectionRequest;
 import org.eclipse.swt.SWT;
@@ -133,7 +132,7 @@ protected boolean handleDoubleClick(int button) {
 	private void performSelection() {
 		if (!m_isSelected) {
 			m_isSelected = true;
-			IEditPartViewer viewer = getCurrentViewer();
+			EditPartViewer viewer = getCurrentViewer();
 			//
 			if ((m_stateMask & SWT.CONTROL) != 0) {
 				if (viewer.getSelectedEditParts().contains(m_sourceEditPart)) {

org.eclipse.wb.core/src-gef/org/eclipse/wb/gef/core/tools/TargetingTool.java

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2011, 2025 Google, Inc. and others.
+ * Copyright (c) 2011, 2026 Google, Inc. and others.
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License 2.0 which is available at
@@ -12,10 +12,9 @@
  *******************************************************************************/
 package org.eclipse.wb.gef.core.tools;
 
-import org.eclipse.wb.gef.core.IEditPartViewer;
-
 import org.eclipse.draw2d.IFigure;
 import org.eclipse.gef.EditPart;
+import org.eclipse.gef.EditPartViewer;
 import org.eclipse.gef.EditPartViewer.Conditional;
 import org.eclipse.gef.Request;
 import org.eclipse.gef.commands.Command;
@@ -27,7 +26,7 @@
  * The base implementation for tools which perform targeting of editparts. Targeting tools may
  * operate using either mouse drags or just mouse moves. Targeting tools work with a <i>target</i>
  * request. This request is used along with the mouse location to obtain an active target from the
- * current {@link IEditPartViewer}. This target is then asked for the <code>{@link Command}</code>
+ * current {@link EditPartViewer}. This target is then asked for the <code>{@link Command}</code>
  * that performs the given request. The target is also asked to show target feedback.
  *
  * @author lobas_av

org.eclipse.wb.core/src-gef/org/eclipse/wb/gef/core/tools/ToolUtilities.java

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2011, 2024 Google, Inc. and others.
+ * Copyright (c) 2011, 2026 Google, Inc. and others.
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License 2.0 which is available at
@@ -12,9 +12,8 @@
  *******************************************************************************/
 package org.eclipse.wb.gef.core.tools;
 
-import org.eclipse.wb.gef.core.IEditPartViewer;
-
 import org.eclipse.gef.EditPart;
+import org.eclipse.gef.EditPartViewer;
 
 import java.util.ArrayList;
 import java.util.Collections;
@@ -31,7 +30,7 @@ public class ToolUtilities {
 	 * Returns a list containing the top level selected {@link EditPart}'s based on the viewer's
 	 * selection. If selection parents of edit parts is differed returns empty list.
 	 */
-	public static List<EditPart> getSelectionWithoutDependants(IEditPartViewer viewer) {
+	public static List<EditPart> getSelectionWithoutDependants(EditPartViewer viewer) {
 		List<EditPart> operationSet = new ArrayList<>();
 		// add selected EditPart's only if their parent is not added yet
 		{

org.eclipse.wb.core/src-gef/org/eclipse/wb/gef/graphical/tools/MarqueeSelectionTool.java

@@ -14,7 +14,6 @@
 
 import org.eclipse.wb.draw2d.Figure;
 import org.eclipse.wb.draw2d.FigureUtils;
-import org.eclipse.wb.gef.core.IEditPartViewer;
 import org.eclipse.wb.gef.core.tools.Tool;
 import org.eclipse.wb.gef.graphical.GraphicalEditPart;
 
@@ -24,6 +23,7 @@
 import org.eclipse.draw2d.IFigure;
 import org.eclipse.draw2d.geometry.Rectangle;
 import org.eclipse.gef.EditPart;
+import org.eclipse.gef.EditPartViewer;
 import org.eclipse.gef.LayerConstants;
 import org.eclipse.gef.Request;
 import org.eclipse.gef.RequestConstants;
@@ -164,7 +164,7 @@ protected boolean handleDragInProgress() {
 	 * the selection and select the new group
 	 */
 	private void performMarqueeSelect() {
-		IEditPartViewer viewer = getCurrentViewer();
+		EditPartViewer viewer = getCurrentViewer();
 		List<EditPart> newSelections = calculateNewSelection();
 		//
 		if (m_selectionMode == APPEND_MODE) {