| /* | |
| * Copyright (c) 1999, 2013, Oracle and/or its affiliates. All rights reserved. | |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. | |
| * | |
| * This code is free software; you can redistribute it and/or modify it | |
| * under the terms of the GNU General Public License version 2 only, as | |
| * published by the Free Software Foundation. Oracle designates this | |
| * particular file as subject to the "Classpath" exception as provided | |
| * by Oracle in the LICENSE file that accompanied this code. | |
| * | |
| * This code is distributed in the hope that it will be useful, but WITHOUT | |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
| * version 2 for more details (a copy is included in the LICENSE file that | |
| * accompanied this code). | |
| * | |
| * You should have received a copy of the GNU General Public License version | |
| * 2 along with this work; if not, write to the Free Software Foundation, | |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. | |
| * | |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA | |
| * or visit www.oracle.com if you need additional information or have any | |
| * questions. | |
| */ | |
| package sun.awt; | |
| import java.awt.*; | |
| import java.awt.event.InputEvent; | |
| import java.awt.event.InvocationEvent; | |
| /** | |
| * A stateless class which responds to native mouse moves, Component resizes, | |
| * Component moves, showing and hiding of Components, minimizing and | |
| * maximizing of top level Windows, addition and removal of Components, | |
| * and calls to setCursor(). | |
| */ | |
| public abstract class GlobalCursorManager { | |
| class NativeUpdater implements Runnable { | |
| boolean pending = false; | |
| public void run() { | |
| boolean shouldUpdate = false; | |
| synchronized (this) { | |
| if (pending) { | |
| pending = false; | |
| shouldUpdate = true; | |
| } | |
| } | |
| if (shouldUpdate) { | |
| _updateCursor(false); | |
| } | |
| } | |
| public void postIfNotPending(Component heavy, InvocationEvent in) { | |
| boolean shouldPost = false; | |
| synchronized (this) { | |
| if (!pending) { | |
| pending = shouldPost = true; | |
| } | |
| } | |
| if (shouldPost) { | |
| SunToolkit.postEvent(SunToolkit.targetToAppContext(heavy), in); | |
| } | |
| } | |
| } | |
| /** | |
| * Use a singleton NativeUpdater for better performance. We cannot use | |
| * a singleton InvocationEvent because we want each event to have a fresh | |
| * timestamp. | |
| */ | |
| private final NativeUpdater nativeUpdater = new NativeUpdater(); | |
| /** | |
| * The last time the cursor was updated, in milliseconds. | |
| */ | |
| private long lastUpdateMillis; | |
| /** | |
| * Locking object for synchronizing access to lastUpdateMillis. The VM | |
| * does not guarantee atomicity of longs. | |
| */ | |
| private final Object lastUpdateLock = new Object(); | |
| /** | |
| * Should be called for any activity at the Java level which may affect | |
| * the global cursor, except for Java MOUSE_MOVED events. | |
| */ | |
| public void updateCursorImmediately() { | |
| synchronized (nativeUpdater) { | |
| nativeUpdater.pending = false; | |
| } | |
| _updateCursor(false); | |
| } | |
| /** | |
| * Should be called in response to Java MOUSE_MOVED events. The update | |
| * will be discarded if the InputEvent is outdated. | |
| * | |
| * @param e the InputEvent which triggered the cursor update. | |
| */ | |
| public void updateCursorImmediately(InputEvent e) { | |
| boolean shouldUpdate; | |
| synchronized (lastUpdateLock) { | |
| shouldUpdate = (e.getWhen() >= lastUpdateMillis); | |
| } | |
| if (shouldUpdate) { | |
| _updateCursor(true); | |
| } | |
| } | |
| /** | |
| * Should be called in response to a native mouse enter or native mouse | |
| * button released message. Should not be called during a mouse drag. | |
| */ | |
| public void updateCursorLater(Component heavy) { | |
| nativeUpdater.postIfNotPending(heavy, new InvocationEvent | |
| (Toolkit.getDefaultToolkit(), nativeUpdater)); | |
| } | |
| protected GlobalCursorManager() { } | |
| /** | |
| * Set the global cursor to the specified cursor. The component over | |
| * which the Cursor current resides is provided as a convenience. Not | |
| * all platforms may require the Component. | |
| */ | |
| protected abstract void setCursor(Component comp, Cursor cursor, | |
| boolean useCache); | |
| /** | |
| * Returns the global cursor position, in screen coordinates. | |
| */ | |
| protected abstract void getCursorPos(Point p); | |
| protected abstract Point getLocationOnScreen(Component com); | |
| /** | |
| * Returns the most specific, visible, heavyweight Component | |
| * under the cursor. This method should return null iff the cursor is | |
| * not over any Java Window. | |
| * | |
| * @param useCache If true, the implementation is free to use caching | |
| * mechanisms because the Z-order, visibility, and enabled state of the | |
| * Components has not changed. If false, the implementation should not | |
| * make these assumptions. | |
| */ | |
| protected abstract Component findHeavyweightUnderCursor(boolean useCache); | |
| /** | |
| * Updates the global cursor. We apply a three-step scheme to cursor | |
| * updates:<p> | |
| * | |
| * (1) InputEvent updates which are outdated are discarded by | |
| * {@code updateCursorImmediately(InputEvent)}.<p> | |
| * | |
| * (2) If 'useCache' is true, the native code is free to use a cached | |
| * value to determine the most specific, visible, enabled heavyweight | |
| * because this update is occurring in response to a mouse move. If | |
| * 'useCache' is false, the native code must perform a new search given | |
| * the current mouse coordinates. | |
| * | |
| * (3) Once we have determined the most specific, visible, enabled | |
| * heavyweight, we use findComponentAt to find the most specific, visible, | |
| * enabled Component. | |
| */ | |
| private void _updateCursor(boolean useCache) { | |
| synchronized (lastUpdateLock) { | |
| lastUpdateMillis = System.currentTimeMillis(); | |
| } | |
| Point queryPos = null, p = null; | |
| Component comp; | |
| try { | |
| comp = findHeavyweightUnderCursor(useCache); | |
| if (comp == null) { | |
| updateCursorOutOfJava(); | |
| return; | |
| } | |
| if (comp instanceof Window) { | |
| p = AWTAccessor.getComponentAccessor().getLocation(comp); | |
| } else if (comp instanceof Container) { | |
| p = getLocationOnScreen(comp); | |
| } | |
| if (p != null) { | |
| queryPos = new Point(); | |
| getCursorPos(queryPos); | |
| Component c = AWTAccessor.getContainerAccessor(). | |
| findComponentAt((Container) comp, | |
| queryPos.x - p.x, queryPos.y - p.y, false); | |
| // If findComponentAt returns null, then something bad has | |
| // happened. For example, the heavyweight Component may | |
| // have been hidden or disabled by another thread. In that | |
| // case, we'll just use the original heavyweight. | |
| if (c != null) { | |
| comp = c; | |
| } | |
| } | |
| setCursor(comp, AWTAccessor.getComponentAccessor().getCursor(comp), useCache); | |
| } catch (IllegalComponentStateException e) { | |
| // Shouldn't happen, but if it does, abort. | |
| } | |
| } | |
| protected void updateCursorOutOfJava() { | |
| // Cursor is not over a Java Window. Do nothing...usually | |
| // But we need to update it in case of grab on X. | |
| } | |
| } |