Use Typed Generics for Handle Generation and Management #155

org.eclipse.gef/.settings/.api_filters

@@ -1,5 +1,21 @@
 <?xml version="1.0" encoding="UTF-8" standalone="no"?>
 <component id="org.eclipse.gef" version="2">
+    <resource path="src/org/eclipse/gef/handles/NonResizableHandleKit.java" type="org.eclipse.gef.handles.NonResizableHandleKit">
+        <filter id="354463860">
+            <message_arguments>
+                <message_argument value="org.eclipse.gef.handles.NonResizableHandleKit"/>
+                <message_argument value="NonResizableHandleKit()"/>
+            </message_arguments>
+        </filter>
+    </resource>
+    <resource path="src/org/eclipse/gef/handles/ResizableHandleKit.java" type="org.eclipse.gef.handles.ResizableHandleKit">
+        <filter id="354463860">
+            <message_arguments>
+                <message_argument value="org.eclipse.gef.handles.ResizableHandleKit"/>
+                <message_argument value="ResizableHandleKit()"/>
+            </message_arguments>
+        </filter>
+    </resource>
     <resource path="src/org/eclipse/gef/ui/actions/AlignmentRetargetAction.java" type="org.eclipse.gef.ui.actions.AlignmentRetargetAction">
         <filter id="571473929">
             <message_arguments>

org.eclipse.gef/src/org/eclipse/gef/editpolicies/BendpointEditPolicy.java

@@ -120,7 +120,7 @@ private List<BendpointHandle> createHandlesForUserBendpoints() {
 	 * @see SelectionHandlesEditPolicy#createSelectionHandles()
 	 */
 	@Override
-	protected List createSelectionHandles() {
+	protected List<? extends BendpointHandle> createSelectionHandles() {
 		if (isAutomaticallyBending()) {
 			return createHandlesForAutomaticBendpoints();
 		}

org.eclipse.gef/src/org/eclipse/gef/editpolicies/ConnectionEndpointEditPolicy.java

@@ -108,7 +108,7 @@ public void validate() {
 	 * @see org.eclipse.gef.editpolicies.SelectionHandlesEditPolicy#createSelectionHandles()
 	 */
 	@Override
-	protected List createSelectionHandles() {
+	protected List<? extends ConnectionEndpointHandle> createSelectionHandles() {
 		List<ConnectionEndpointHandle> list = new ArrayList<>();
 		list.add(new ConnectionEndpointHandle((ConnectionEditPart) getHost(), ConnectionLocator.SOURCE));
 		list.add(new ConnectionEndpointHandle((ConnectionEditPart) getHost(), ConnectionLocator.TARGET));

org.eclipse.gef/src/org/eclipse/gef/editpolicies/NonResizableEditPolicy.java

@@ -30,7 +30,6 @@
 import org.eclipse.gef.Handle;
 import org.eclipse.gef.Request;
 import org.eclipse.gef.RequestConstants;
-import org.eclipse.gef.SharedCursors;
 import org.eclipse.gef.commands.Command;
 import org.eclipse.gef.handles.AbstractHandle;
 import org.eclipse.gef.handles.HandleBounds;
@@ -82,7 +81,7 @@ protected IFigure createDragSourceFeedbackFigure() {
 	 * @see org.eclipse.gef.editpolicies.SelectionHandlesEditPolicy#createSelectionHandles()
 	 */
 	@Override
-	protected List createSelectionHandles() {
+	protected List<? extends Handle> createSelectionHandles() {
 		List<Handle> list = new ArrayList<>();
 		createMoveHandle(list);
 		createDragHandle(list, PositionConstants.NORTH_EAST);
@@ -102,14 +101,14 @@ protected List createSelectionHandles() {
 	 *                  handle for
 	 * @since 3.7
 	 */
-	protected void createDragHandle(List handles, int direction) {
+	protected void createDragHandle(List<Handle> handles, int direction) {
 		if (isDragAllowed()) {
 			// display 'resize' handles to allow dragging (drag tracker)
-			NonResizableHandleKit.addHandle(getHost(), handles, direction, getDragTracker(), SharedCursors.SIZEALL);
+			NonResizableHandleKit.addHandle(getHost(), handles, direction, getDragTracker(), Cursors.SIZEALL);
 		} else {
 			// display 'resize' handles to indicate selection only (selection
 			// tracker)
-			NonResizableHandleKit.addHandle(getHost(), handles, direction, getSelectTracker(), SharedCursors.ARROW);
+			NonResizableHandleKit.addHandle(getHost(), handles, direction, getSelectTracker(), Cursors.ARROW);
 		}
 	}
 
@@ -141,13 +140,13 @@ protected DragEditPartsTracker getDragTracker() {
 	 * @param handles The list of handles to add the move handle to.
 	 * @since 3.7
 	 */
-	protected void createMoveHandle(List handles) {
+	protected void createMoveHandle(List<Handle> handles) {
 		if (isDragAllowed()) {
 			// display 'move' handle to allow dragging
 			ResizableHandleKit.addMoveHandle(getHost(), handles, getDragTracker(), Cursors.SIZEALL);
 		} else {
 			// display 'move' handle only to indicate selection
-			ResizableHandleKit.addMoveHandle(getHost(), handles, getSelectTracker(), SharedCursors.ARROW);
+			ResizableHandleKit.addMoveHandle(getHost(), handles, getSelectTracker(), Cursors.ARROW);
 		}
 	}
 
@@ -278,6 +277,7 @@ protected Command getMoveCommand(ChangeBoundsRequest request) {
 	 * @param req the orphan request
 	 * @return <code>null</code> by default
 	 */
+	@SuppressWarnings("static-method")
 	protected Command getOrphanCommand(Request req) {
 		return null;
 	}
@@ -324,16 +324,16 @@ public void setDragAllowed(boolean isDragAllowed) {
 	 * @param request the request
 	 */
 	protected void showChangeBoundsFeedback(ChangeBoundsRequest request) {
-		IFigure feedback = getDragSourceFeedbackFigure();
+		IFigure dsFeedbackFigure = getDragSourceFeedbackFigure();
 
 		PrecisionRectangle rect = new PrecisionRectangle(getInitialFeedbackBounds().getCopy());
 		getHostFigure().translateToAbsolute(rect);
 		rect.translate(request.getMoveDelta());
 		rect.resize(request.getSizeDelta());
 
-		feedback.translateToRelative(rect);
-		feedback.setBounds(rect);
-		feedback.validate();
+		dsFeedbackFigure.translateToRelative(rect);
+		dsFeedbackFigure.setBounds(rect);
+		dsFeedbackFigure.validate();
 	}
 
 	/**

org.eclipse.gef/src/org/eclipse/gef/editpolicies/ResizableEditPolicy.java

@@ -44,19 +44,11 @@ public class ResizableEditPolicy extends NonResizableEditPolicy {
 
 	private int resizeDirections = PositionConstants.NSEW;
 
-	/**
-	 * Constructs a new {@link ResizableEditPolicy}.
-	 *
-	 * @since 3.7
-	 */
-	public ResizableEditPolicy() {
-	}
-
 	/**
 	 * @see org.eclipse.gef.editpolicies.SelectionHandlesEditPolicy#createSelectionHandles()
 	 */
 	@Override
-	protected List createSelectionHandles() {
+	protected List<? extends Handle> createSelectionHandles() {
 		if (resizeDirections == PositionConstants.NONE) {
 			// non resizable, so delegate to super implementation
 			return super.createSelectionHandles();
@@ -87,7 +79,7 @@ protected List createSelectionHandles() {
 	 *                  handle for
 	 * @since 3.7
 	 */
-	protected void createResizeHandle(List handles, int direction) {
+	protected void createResizeHandle(List<Handle> handles, int direction) {
 		if ((resizeDirections & direction) == direction) {
 			ResizableHandleKit.addHandle(getHost(), handles, direction, getResizeTracker(direction),
 					Cursors.getDirectionalCursor(direction, getHostFigure().isMirrored()));
@@ -195,8 +187,8 @@ public void showSourceFeedback(Request request) {
 	public boolean understandsRequest(Request request) {
 		if (REQ_RESIZE.equals(request.getType())) {
 			// check all resize directions of the request are supported
-			int resizeDirections = ((ChangeBoundsRequest) request).getResizeDirection();
-			return (resizeDirections & getResizeDirections()) == resizeDirections;
+			int reqResizeDirection = ((ChangeBoundsRequest) request).getResizeDirection();
+			return (reqResizeDirection & getResizeDirections()) == reqResizeDirection;
 		}
 		return super.understandsRequest(request);
 	}

org.eclipse.gef/src/org/eclipse/gef/editpolicies/SelectionHandlesEditPolicy.java

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2000, 2010 IBM Corporation and others.
+ * Copyright (c) 2000, 2024 IBM Corporation 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
@@ -14,6 +14,7 @@
 
 import java.util.ArrayList;
 import java.util.List;
+import java.util.stream.Stream;
 
 import org.eclipse.core.runtime.IAdaptable;
 
@@ -42,7 +43,7 @@ public abstract class SelectionHandlesEditPolicy extends SelectionEditPolicy imp
 	/**
 	 * the List of handles
 	 */
-	protected List handles;
+	protected List<? extends Handle> handles;
 
 	/**
 	 * Adds the handles to the handle layer.
@@ -51,43 +52,43 @@ protected void addSelectionHandles() {
 		removeSelectionHandles();
 		IFigure layer = getLayer(LayerConstants.HANDLE_LAYER);
 		handles = createSelectionHandles();
-		for (Object handle : handles) {
-			layer.add((IFigure) handle);
-		}
+		getHandleFigures().forEach(layer::add);
 	}
 
 	/**
 	 * Subclasses must implement to provide the list of handles.
 	 *
 	 * @return List of handles; cannot be <code>null</code>
 	 */
-	protected abstract List createSelectionHandles();
+	protected abstract List<? extends Handle> createSelectionHandles();
 
 	/**
 	 * @see org.eclipse.core.runtime.IAdaptable#getAdapter(Class)
 	 */
 	@Override
 	public <T> T getAdapter(final Class<T> key) {
 		if (key == AccessibleHandleProvider.class) {
-			return key.cast(new AccessibleHandleProvider() {
-				@Override
-				public List<Point> getAccessibleHandleLocations() {
-					List<Point> result = new ArrayList<>();
-					if (handles != null) {
-						for (Object handle : handles) {
-							Point p = ((Handle) handle).getAccessibleLocation();
-							if (p != null) {
-								result.add(p);
-							}
+			return key.cast((AccessibleHandleProvider) () -> {
+				List<Point> result = new ArrayList<>();
+				if (handles != null) {
+					for (Handle handle : handles) {
+						Point p = handle.getAccessibleLocation();
+						if (p != null) {
+							result.add(p);
 						}
 					}
-					return result;
 				}
+				return result;
 			});
 		}
 		return null;
 	}
 
+	private Stream<IFigure> getHandleFigures() {
+		return (handles != null) ? handles.stream().filter(IFigure.class::isInstance).map(IFigure.class::cast)
+				: Stream.empty();
+	}
+
 	/**
 	 * Implemented to remove the handles.
 	 *
@@ -106,9 +107,7 @@ protected void removeSelectionHandles() {
 			return;
 		}
 		IFigure layer = getLayer(LayerConstants.HANDLE_LAYER);
-		for (Object handle : handles) {
-			layer.remove((IFigure) handle);
-		}
+		getHandleFigures().forEach(layer::remove);
 		handles = null;
 	}
 

org.eclipse.gef/src/org/eclipse/gef/handles/NonResizableHandleKit.java

@@ -16,12 +16,12 @@
 
 import org.eclipse.swt.graphics.Cursor;
 
+import org.eclipse.draw2d.Cursors;
 import org.eclipse.draw2d.PositionConstants;
 
 import org.eclipse.gef.DragTracker;
 import org.eclipse.gef.GraphicalEditPart;
 import org.eclipse.gef.Handle;
-import org.eclipse.gef.SharedCursors;
 import org.eclipse.gef.tools.DragEditPartsTracker;
 
 /**
@@ -39,7 +39,8 @@ public class NonResizableHandleKit {
 	 * @param tracker the handles' DragTracker
 	 * @param cursor  the handles' Cursor
 	 */
-	public static void addCornerHandles(GraphicalEditPart part, List handles, DragTracker tracker, Cursor cursor) {
+	public static void addCornerHandles(GraphicalEditPart part, List<Handle> handles, DragTracker tracker,
+			Cursor cursor) {
 		handles.add(createHandle(part, PositionConstants.SOUTH_EAST, tracker, cursor));
 		handles.add(createHandle(part, PositionConstants.SOUTH_WEST, tracker, cursor));
 		handles.add(createHandle(part, PositionConstants.NORTH_WEST, tracker, cursor));
@@ -52,7 +53,7 @@ public static void addCornerHandles(GraphicalEditPart part, List handles, DragTr
 	 * @param part    the handles' GraphicalEditPart
 	 * @param handles the List to add the four corner handles to
 	 */
-	public static void addCornerHandles(GraphicalEditPart part, List handles) {
+	public static void addCornerHandles(GraphicalEditPart part, List<Handle> handles) {
 		handles.add(createHandle(part, PositionConstants.SOUTH_EAST));
 		handles.add(createHandle(part, PositionConstants.SOUTH_WEST));
 		handles.add(createHandle(part, PositionConstants.NORTH_WEST));
@@ -67,7 +68,7 @@ public static void addCornerHandles(GraphicalEditPart part, List handles) {
 	 * @param direction the integer constant from PositionConstants that refers to
 	 *                  the handle direction
 	 */
-	public static void addHandle(GraphicalEditPart part, List handles, int direction) {
+	public static void addHandle(GraphicalEditPart part, List<Handle> handles, int direction) {
 		handles.add(createHandle(part, direction));
 	}
 
@@ -81,7 +82,7 @@ public static void addHandle(GraphicalEditPart part, List handles, int direction
 	 *                  the handle direction
 	 * @param cursor    the Cursor to use when hovering over this handle
 	 */
-	public static void addHandle(GraphicalEditPart part, List handles, int direction, DragTracker tracker,
+	public static void addHandle(GraphicalEditPart part, List<Handle> handles, int direction, DragTracker tracker,
 			Cursor cursor) {
 		handles.add(createHandle(part, direction, tracker, cursor));
 	}
@@ -93,7 +94,8 @@ public static void addHandle(GraphicalEditPart part, List handles, int direction
 	 * @param handles the List to add the handles to
 	 * @deprecated
 	 */
-	public static void addHandles(GraphicalEditPart part, List handles) {
+	@Deprecated
+	public static void addHandles(GraphicalEditPart part, List<Handle> handles) {
 		addMoveHandle(part, handles);
 		addCornerHandles(part, handles);
 	}
@@ -107,7 +109,8 @@ public static void addHandles(GraphicalEditPart part, List handles) {
 	 * @param cursor  the handles' Cursor
 	 * @deprecated
 	 */
-	public static void addHandles(GraphicalEditPart part, List handles, DragTracker tracker, Cursor cursor) {
+	@Deprecated
+	public static void addHandles(GraphicalEditPart part, List<Handle> handles, DragTracker tracker, Cursor cursor) {
 		addMoveHandle(part, handles, tracker, cursor);
 		addCornerHandles(part, handles, tracker, cursor);
 	}
@@ -118,7 +121,7 @@ public static void addHandles(GraphicalEditPart part, List handles, DragTracker
 	 * @param f       the handles' GraphicalEditPart
 	 * @param handles the List to add the handles to
 	 */
-	public static void addMoveHandle(GraphicalEditPart f, List handles) {
+	public static void addMoveHandle(GraphicalEditPart f, List<Handle> handles) {
 		handles.add(moveHandle(f));
 	}
 
@@ -130,13 +133,13 @@ public static void addMoveHandle(GraphicalEditPart f, List handles) {
 	 * @param handles the List to add the handles to
 	 * @param cursor  the Cursor to use when hovering over this handle
 	 */
-	public static void addMoveHandle(GraphicalEditPart f, List handles, DragTracker tracker, Cursor cursor) {
+	public static void addMoveHandle(GraphicalEditPart f, List<Handle> handles, DragTracker tracker, Cursor cursor) {
 		handles.add(moveHandle(f, tracker, cursor));
 	}
 
 	static Handle createHandle(GraphicalEditPart owner, int direction) {
 		ResizeHandle handle = new ResizeHandle(owner, direction);
-		handle.setCursor(SharedCursors.SIZEALL);
+		handle.setCursor(Cursors.SIZEALL);
 		handle.setDragTracker(new DragEditPartsTracker(owner));
 		return handle;
 	}
@@ -173,4 +176,8 @@ public static Handle moveHandle(GraphicalEditPart owner, DragTracker tracker, Cu
 		return moveHandle;
 	}
 
+	private NonResizableHandleKit() {
+		throw new UnsupportedOperationException("Helper class should not be instantiated!"); //$NON-NLS-1$
+	}
+
 }