diff -r 4ebc2e2fb97c -r 71c04702a3d5 src/java.desktop/share/classes/javax/swing/RepaintManager.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/java.desktop/share/classes/javax/swing/RepaintManager.java	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,1890 @@
+/*
+ * Copyright (c) 1997, 2015, 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 javax.swing;
+
+
+import java.awt.*;
+import java.awt.event.*;
+import java.awt.image.VolatileImage;
+import java.security.AccessControlContext;
+import java.security.AccessController;
+import java.security.PrivilegedAction;
+import java.util.*;
+import java.util.concurrent.atomic.AtomicInteger;
+import java.applet.*;
+
+import jdk.internal.misc.JavaSecurityAccess;
+import jdk.internal.misc.SharedSecrets;
+import sun.awt.AWTAccessor;
+import sun.awt.AppContext;
+import sun.awt.DisplayChangedListener;
+import sun.awt.SunToolkit;
+import sun.java2d.SunGraphicsEnvironment;
+import sun.security.action.GetPropertyAction;
+
+import com.sun.java.swing.SwingUtilities3;
+import java.awt.geom.AffineTransform;
+import sun.java2d.SunGraphics2D;
+import sun.java2d.pipe.Region;
+import sun.swing.SwingAccessor;
+import sun.swing.SwingUtilities2;
+import sun.swing.SwingUtilities2.RepaintListener;
+
+/**
+ * This class manages repaint requests, allowing the number
+ * of repaints to be minimized, for example by collapsing multiple
+ * requests into a single repaint for members of a component tree.
+ * <p>
+ * As of 1.6 <code>RepaintManager</code> handles repaint requests
+ * for Swing's top level components (<code>JApplet</code>,
+ * <code>JWindow</code>, <code>JFrame</code> and <code>JDialog</code>).
+ * Any calls to <code>repaint</code> on one of these will call into the
+ * appropriate <code>addDirtyRegion</code> method.
+ *
+ * @author Arnaud Weber
+ * @since 1.2
+ */
+public class RepaintManager
+{
+    /**
+     * Whether or not the RepaintManager should handle paint requests
+     * for top levels.
+     */
+    static final boolean HANDLE_TOP_LEVEL_PAINT;
+
+    private static final short BUFFER_STRATEGY_NOT_SPECIFIED = 0;
+    private static final short BUFFER_STRATEGY_SPECIFIED_ON = 1;
+    private static final short BUFFER_STRATEGY_SPECIFIED_OFF = 2;
+
+    private static final short BUFFER_STRATEGY_TYPE;
+
+    /**
+     * Maps from GraphicsConfiguration to VolatileImage.
+     */
+    private Map<GraphicsConfiguration,VolatileImage> volatileMap = new
+                        HashMap<GraphicsConfiguration,VolatileImage>(1);
+
+    //
+    // As of 1.6 Swing handles scheduling of paint events from native code.
+    // That is, SwingPaintEventDispatcher is invoked on the toolkit thread,
+    // which in turn invokes nativeAddDirtyRegion.  Because this is invoked
+    // from the native thread we can not invoke any public methods and so
+    // we introduce these added maps.  So, any time nativeAddDirtyRegion is
+    // invoked the region is added to hwDirtyComponents and a work request
+    // is scheduled.  When the work request is processed all entries in
+    // this map are pushed to the real map (dirtyComponents) and then
+    // painted with the rest of the components.
+    //
+    private Map<Container,Rectangle> hwDirtyComponents;
+
+    private Map<Component,Rectangle> dirtyComponents;
+    private Map<Component,Rectangle> tmpDirtyComponents;
+    private java.util.List<Component> invalidComponents;
+
+    // List of Runnables that need to be processed before painting from AWT.
+    private java.util.List<Runnable> runnableList;
+
+    boolean   doubleBufferingEnabled = true;
+
+    private Dimension doubleBufferMaxSize;
+
+    // Support for both the standard and volatile offscreen buffers exists to
+    // provide backwards compatibility for the [rare] programs which may be
+    // calling getOffScreenBuffer() and not expecting to get a VolatileImage.
+    // Swing internally is migrating to use *only* the volatile image buffer.
+
+    // Support for standard offscreen buffer
+    //
+    DoubleBufferInfo standardDoubleBuffer;
+
+    /**
+     * Object responsible for hanlding core paint functionality.
+     */
+    private PaintManager paintManager;
+
+    private static final Object repaintManagerKey = RepaintManager.class;
+
+    // Whether or not a VolatileImage should be used for double-buffered painting
+    static boolean volatileImageBufferEnabled = true;
+    /**
+     * Type of VolatileImage which should be used for double-buffered
+     * painting.
+     */
+    private static final int volatileBufferType;
+    /**
+     * Value of the system property awt.nativeDoubleBuffering.
+     */
+    private static boolean nativeDoubleBuffering;
+
+    // The maximum number of times Swing will attempt to use the VolatileImage
+    // buffer during a paint operation.
+    private static final int VOLATILE_LOOP_MAX = 2;
+
+    /**
+     * Number of <code>beginPaint</code> that have been invoked.
+     */
+    private int paintDepth = 0;
+
+    /**
+     * Type of buffer strategy to use.  Will be one of the BUFFER_STRATEGY_
+     * constants.
+     */
+    private short bufferStrategyType;
+
+    //
+    // BufferStrategyPaintManager has the unique characteristic that it
+    // must deal with the buffer being lost while painting to it.  For
+    // example, if we paint a component and show it and the buffer has
+    // become lost we must repaint the whole window.  To deal with that
+    // the PaintManager calls into repaintRoot, and if we're still in
+    // the process of painting the repaintRoot field is set to the JRootPane
+    // and after the current JComponent.paintImmediately call finishes
+    // paintImmediately will be invoked on the repaintRoot.  In this
+    // way we don't try to show garbage to the screen.
+    //
+    /**
+     * True if we're in the process of painting the dirty regions.  This is
+     * set to true in <code>paintDirtyRegions</code>.
+     */
+    private boolean painting;
+    /**
+     * If the PaintManager calls into repaintRoot during painting this field
+     * will be set to the root.
+     */
+    private JComponent repaintRoot;
+
+    /**
+     * The Thread that has initiated painting.  If null it
+     * indicates painting is not currently in progress.
+     */
+    private Thread paintThread;
+
+    /**
+     * Runnable used to process all repaint/revalidate requests.
+     */
+    private final ProcessingRunnable processingRunnable;
+
+    private static final JavaSecurityAccess javaSecurityAccess =
+            SharedSecrets.getJavaSecurityAccess();
+
+    /**
+     * Listener installed to detect display changes. When display changes,
+     * schedules a callback to notify all RepaintManagers of the display
+     * changes.
+     */
+    private static final DisplayChangedListener displayChangedHandler =
+            new DisplayChangedHandler();
+
+    static {
+        SwingAccessor.setRepaintManagerAccessor(new SwingAccessor.RepaintManagerAccessor() {
+            @Override
+            public void addRepaintListener(RepaintManager rm, RepaintListener l) {
+                rm.addRepaintListener(l);
+            }
+            @Override
+            public void removeRepaintListener(RepaintManager rm, RepaintListener l) {
+                rm.removeRepaintListener(l);
+            }
+        });
+
+        volatileImageBufferEnabled = "true".equals(AccessController.
+                doPrivileged(new GetPropertyAction(
+                "swing.volatileImageBufferEnabled", "true")));
+        boolean headless = GraphicsEnvironment.isHeadless();
+        if (volatileImageBufferEnabled && headless) {
+            volatileImageBufferEnabled = false;
+        }
+        nativeDoubleBuffering = "true".equals(AccessController.doPrivileged(
+                    new GetPropertyAction("awt.nativeDoubleBuffering")));
+        String bs = AccessController.doPrivileged(
+                          new GetPropertyAction("swing.bufferPerWindow"));
+        if (headless) {
+            BUFFER_STRATEGY_TYPE = BUFFER_STRATEGY_SPECIFIED_OFF;
+        }
+        else if (bs == null) {
+            BUFFER_STRATEGY_TYPE = BUFFER_STRATEGY_NOT_SPECIFIED;
+        }
+        else if ("true".equals(bs)) {
+            BUFFER_STRATEGY_TYPE = BUFFER_STRATEGY_SPECIFIED_ON;
+        }
+        else {
+            BUFFER_STRATEGY_TYPE = BUFFER_STRATEGY_SPECIFIED_OFF;
+        }
+        HANDLE_TOP_LEVEL_PAINT = "true".equals(AccessController.doPrivileged(
+               new GetPropertyAction("swing.handleTopLevelPaint", "true")));
+        GraphicsEnvironment ge = GraphicsEnvironment.
+                getLocalGraphicsEnvironment();
+        if (ge instanceof SunGraphicsEnvironment) {
+            ((SunGraphicsEnvironment) ge).addDisplayChangedListener(
+                    displayChangedHandler);
+        }
+        Toolkit tk = Toolkit.getDefaultToolkit();
+        if ((tk instanceof SunToolkit)
+                && ((SunToolkit) tk).isSwingBackbufferTranslucencySupported()) {
+            volatileBufferType = Transparency.TRANSLUCENT;
+        } else {
+            volatileBufferType = Transparency.OPAQUE;
+        }
+    }
+
+    /**
+     * Return the RepaintManager for the calling thread given a Component.
+     *
+     * @param c a Component -- unused in the default implementation, but could
+     *          be used by an overridden version to return a different RepaintManager
+     *          depending on the Component
+     * @return the RepaintManager object
+     */
+    public static RepaintManager currentManager(Component c) {
+        // Note: DisplayChangedRunnable passes in null as the component, so if
+        // component is ever used to determine the current
+        // RepaintManager, DisplayChangedRunnable will need to be modified
+        // accordingly.
+        return currentManager(AppContext.getAppContext());
+    }
+
+    /**
+     * Returns the RepaintManager for the specified AppContext.  If
+     * a RepaintManager has not been created for the specified
+     * AppContext this will return null.
+     */
+    static RepaintManager currentManager(AppContext appContext) {
+        RepaintManager rm = (RepaintManager)appContext.get(repaintManagerKey);
+        if (rm == null) {
+            rm = new RepaintManager(BUFFER_STRATEGY_TYPE);
+            appContext.put(repaintManagerKey, rm);
+        }
+        return rm;
+    }
+
+    /**
+     * Return the RepaintManager for the calling thread given a JComponent.
+     * <p>
+    * Note: This method exists for backward binary compatibility with earlier
+     * versions of the Swing library. It simply returns the result returned by
+     * {@link #currentManager(Component)}.
+     *
+     * @param c a JComponent -- unused
+     * @return the RepaintManager object
+     */
+    public static RepaintManager currentManager(JComponent c) {
+        return currentManager((Component)c);
+    }
+
+
+    /**
+     * Set the RepaintManager that should be used for the calling
+     * thread. <b>aRepaintManager</b> will become the current RepaintManager
+     * for the calling thread's thread group.
+     * @param aRepaintManager  the RepaintManager object to use
+     */
+    public static void setCurrentManager(RepaintManager aRepaintManager) {
+        if (aRepaintManager != null) {
+            SwingUtilities.appContextPut(repaintManagerKey, aRepaintManager);
+        } else {
+            SwingUtilities.appContextRemove(repaintManagerKey);
+        }
+    }
+
+    /**
+     * Create a new RepaintManager instance. You rarely call this constructor.
+     * directly. To get the default RepaintManager, use
+     * RepaintManager.currentManager(JComponent) (normally "this").
+     */
+    public RepaintManager() {
+        // Because we can't know what a subclass is doing with the
+        // volatile image we immediately punt in subclasses.  If this
+        // poses a problem we'll need a more sophisticated detection algorithm,
+        // or API.
+        this(BUFFER_STRATEGY_SPECIFIED_OFF);
+    }
+
+    private RepaintManager(short bufferStrategyType) {
+        // If native doublebuffering is being used, do NOT use
+        // Swing doublebuffering.
+        doubleBufferingEnabled = !nativeDoubleBuffering;
+        synchronized(this) {
+            dirtyComponents = new IdentityHashMap<Component,Rectangle>();
+            tmpDirtyComponents = new IdentityHashMap<Component,Rectangle>();
+            this.bufferStrategyType = bufferStrategyType;
+            hwDirtyComponents = new IdentityHashMap<Container,Rectangle>();
+        }
+        processingRunnable = new ProcessingRunnable();
+    }
+
+    private void displayChanged() {
+        clearImages();
+    }
+
+    /**
+     * Mark the component as in need of layout and queue a runnable
+     * for the event dispatching thread that will validate the components
+     * first isValidateRoot() ancestor.
+     *
+     * @param invalidComponent a component
+     * @see JComponent#isValidateRoot
+     * @see #removeInvalidComponent
+     */
+    public synchronized void addInvalidComponent(JComponent invalidComponent)
+    {
+        RepaintManager delegate = getDelegate(invalidComponent);
+        if (delegate != null) {
+            delegate.addInvalidComponent(invalidComponent);
+            return;
+        }
+        Component validateRoot =
+            SwingUtilities.getValidateRoot(invalidComponent, true);
+
+        if (validateRoot == null) {
+            return;
+        }
+
+        /* Lazily create the invalidateComponents vector and add the
+         * validateRoot if it's not there already.  If this validateRoot
+         * is already in the vector, we're done.
+         */
+        if (invalidComponents == null) {
+            invalidComponents = new ArrayList<Component>();
+        }
+        else {
+            int n = invalidComponents.size();
+            for(int i = 0; i < n; i++) {
+                if(validateRoot == invalidComponents.get(i)) {
+                    return;
+                }
+            }
+        }
+        invalidComponents.add(validateRoot);
+
+        // Queue a Runnable to invoke paintDirtyRegions and
+        // validateInvalidComponents.
+        scheduleProcessingRunnable(SunToolkit.targetToAppContext(invalidComponent));
+    }
+
+
+    /**
+     * Remove a component from the list of invalid components.
+     *
+     * @param component a component
+     * @see #addInvalidComponent
+     */
+    public synchronized void removeInvalidComponent(JComponent component) {
+        RepaintManager delegate = getDelegate(component);
+        if (delegate != null) {
+            delegate.removeInvalidComponent(component);
+            return;
+        }
+        if(invalidComponents != null) {
+            int index = invalidComponents.indexOf(component);
+            if(index != -1) {
+                invalidComponents.remove(index);
+            }
+        }
+    }
+
+
+    /**
+     * Add a component in the list of components that should be refreshed.
+     * If <i>c</i> already has a dirty region, the rectangle <i>(x,y,w,h)</i>
+     * will be unioned with the region that should be redrawn.
+     *
+     * @see JComponent#repaint
+     */
+    @SuppressWarnings("deprecation")
+    private void addDirtyRegion0(Container c, int x, int y, int w, int h) {
+        /* Special cases we don't have to bother with.
+         */
+        if ((w <= 0) || (h <= 0) || (c == null)) {
+            return;
+        }
+
+        if ((c.getWidth() <= 0) || (c.getHeight() <= 0)) {
+            return;
+        }
+
+        if (extendDirtyRegion(c, x, y, w, h)) {
+            // Component was already marked as dirty, region has been
+            // extended, no need to continue.
+            return;
+        }
+
+        /* Make sure that c and all it ancestors (up to an Applet or
+         * Window) are visible.  This loop has the same effect as
+         * checking c.isShowing() (and note that it's still possible
+         * that c is completely obscured by an opaque ancestor in
+         * the specified rectangle).
+         */
+        Component root = null;
+
+        // Note: We can't synchronize around this, Frame.getExtendedState
+        // is synchronized so that if we were to synchronize around this
+        // it could lead to the possibility of getting locks out
+        // of order and deadlocking.
+        for (Container p = c; p != null; p = p.getParent()) {
+            if (!p.isVisible() || !p.isDisplayable()) {
+                return;
+            }
+            if ((p instanceof Window) || (p instanceof Applet)) {
+                // Iconified frames are still visible!
+                if (p instanceof Frame &&
+                        (((Frame)p).getExtendedState() & Frame.ICONIFIED) ==
+                                    Frame.ICONIFIED) {
+                    return;
+                }
+                root = p;
+                break;
+            }
+        }
+
+        if (root == null) return;
+
+        synchronized(this) {
+            if (extendDirtyRegion(c, x, y, w, h)) {
+                // In between last check and this check another thread
+                // queued up runnable, can bail here.
+                return;
+            }
+            dirtyComponents.put(c, new Rectangle(x, y, w, h));
+        }
+
+        // Queue a Runnable to invoke paintDirtyRegions and
+        // validateInvalidComponents.
+        scheduleProcessingRunnable(SunToolkit.targetToAppContext(c));
+    }
+
+    /**
+     * Add a component in the list of components that should be refreshed.
+     * If <i>c</i> already has a dirty region, the rectangle <i>(x,y,w,h)</i>
+     * will be unioned with the region that should be redrawn.
+     *
+     * @param c Component to repaint, null results in nothing happening.
+     * @param x X coordinate of the region to repaint
+     * @param y Y coordinate of the region to repaint
+     * @param w Width of the region to repaint
+     * @param h Height of the region to repaint
+     * @see JComponent#repaint
+     */
+    public void addDirtyRegion(JComponent c, int x, int y, int w, int h)
+    {
+        RepaintManager delegate = getDelegate(c);
+        if (delegate != null) {
+            delegate.addDirtyRegion(c, x, y, w, h);
+            return;
+        }
+        addDirtyRegion0(c, x, y, w, h);
+    }
+
+    /**
+     * Adds <code>window</code> to the list of <code>Component</code>s that
+     * need to be repainted.
+     *
+     * @param window Window to repaint, null results in nothing happening.
+     * @param x X coordinate of the region to repaint
+     * @param y Y coordinate of the region to repaint
+     * @param w Width of the region to repaint
+     * @param h Height of the region to repaint
+     * @see JFrame#repaint
+     * @see JWindow#repaint
+     * @see JDialog#repaint
+     * @since 1.6
+     */
+    public void addDirtyRegion(Window window, int x, int y, int w, int h) {
+        addDirtyRegion0(window, x, y, w, h);
+    }
+
+    /**
+     * Adds <code>applet</code> to the list of <code>Component</code>s that
+     * need to be repainted.
+     *
+     * @param applet Applet to repaint, null results in nothing happening.
+     * @param x X coordinate of the region to repaint
+     * @param y Y coordinate of the region to repaint
+     * @param w Width of the region to repaint
+     * @param h Height of the region to repaint
+     * @see JApplet#repaint
+     * @since 1.6
+     *
+     * @deprecated The Applet API is deprecated. See the
+     * <a href="../../java/applet/package-summary.html"> java.applet package
+     * documentation</a> for further information.
+     */
+    @Deprecated(since = "9")
+    public void addDirtyRegion(Applet applet, int x, int y, int w, int h) {
+        addDirtyRegion0(applet, x, y, w, h);
+    }
+
+    @SuppressWarnings("deprecation")
+    void scheduleHeavyWeightPaints() {
+        Map<Container,Rectangle> hws;
+
+        synchronized(this) {
+            if (hwDirtyComponents.size() == 0) {
+                return;
+            }
+            hws = hwDirtyComponents;
+            hwDirtyComponents =  new IdentityHashMap<Container,Rectangle>();
+        }
+        for (Container hw : hws.keySet()) {
+            Rectangle dirty = hws.get(hw);
+            if (hw instanceof Window) {
+                addDirtyRegion((Window)hw, dirty.x, dirty.y,
+                               dirty.width, dirty.height);
+            }
+            else if (hw instanceof Applet) {
+                addDirtyRegion((Applet)hw, dirty.x, dirty.y,
+                               dirty.width, dirty.height);
+            }
+            else { // SwingHeavyWeight
+                addDirtyRegion0(hw, dirty.x, dirty.y,
+                                dirty.width, dirty.height);
+            }
+        }
+    }
+
+    //
+    // This is called from the toolkit thread when a native expose is
+    // received.
+    //
+    void nativeAddDirtyRegion(AppContext appContext, Container c,
+                              int x, int y, int w, int h) {
+        if (w > 0 && h > 0) {
+            synchronized(this) {
+                Rectangle dirty = hwDirtyComponents.get(c);
+                if (dirty == null) {
+                    hwDirtyComponents.put(c, new Rectangle(x, y, w, h));
+                }
+                else {
+                    hwDirtyComponents.put(c, SwingUtilities.computeUnion(
+                                              x, y, w, h, dirty));
+                }
+            }
+            scheduleProcessingRunnable(appContext);
+        }
+    }
+
+    //
+    // This is called from the toolkit thread when awt needs to run a
+    // Runnable before we paint.
+    //
+    void nativeQueueSurfaceDataRunnable(AppContext appContext,
+                                        final Component c, final Runnable r)
+    {
+        synchronized(this) {
+            if (runnableList == null) {
+                runnableList = new LinkedList<Runnable>();
+            }
+            runnableList.add(new Runnable() {
+                public void run() {
+                    AccessControlContext stack = AccessController.getContext();
+                    AccessControlContext acc =
+                        AWTAccessor.getComponentAccessor().getAccessControlContext(c);
+                    javaSecurityAccess.doIntersectionPrivilege(new PrivilegedAction<Void>() {
+                        public Void run() {
+                            r.run();
+                            return null;
+                        }
+                    }, stack, acc);
+                }
+            });
+        }
+        scheduleProcessingRunnable(appContext);
+    }
+
+    /**
+     * Extends the dirty region for the specified component to include
+     * the new region.
+     *
+     * @return false if <code>c</code> is not yet marked dirty.
+     */
+    private synchronized boolean extendDirtyRegion(
+        Component c, int x, int y, int w, int h) {
+        Rectangle r = dirtyComponents.get(c);
+        if (r != null) {
+            // A non-null r implies c is already marked as dirty,
+            // and that the parent is valid. Therefore we can
+            // just union the rect and bail.
+            SwingUtilities.computeUnion(x, y, w, h, r);
+            return true;
+        }
+        return false;
+    }
+
+    /**
+     * Return the current dirty region for a component.
+     * Return an empty rectangle if the component is not
+     * dirty.
+     *
+     * @param aComponent a component
+     * @return the region
+     */
+    public Rectangle getDirtyRegion(JComponent aComponent) {
+        RepaintManager delegate = getDelegate(aComponent);
+        if (delegate != null) {
+            return delegate.getDirtyRegion(aComponent);
+        }
+        Rectangle r;
+        synchronized(this) {
+            r = dirtyComponents.get(aComponent);
+        }
+        if(r == null)
+            return new Rectangle(0,0,0,0);
+        else
+            return new Rectangle(r);
+    }
+
+    /**
+     * Mark a component completely dirty. <b>aComponent</b> will be
+     * completely painted during the next paintDirtyRegions() call.
+     *
+     * @param aComponent a component
+     */
+    public void markCompletelyDirty(JComponent aComponent) {
+        RepaintManager delegate = getDelegate(aComponent);
+        if (delegate != null) {
+            delegate.markCompletelyDirty(aComponent);
+            return;
+        }
+        addDirtyRegion(aComponent,0,0,Integer.MAX_VALUE,Integer.MAX_VALUE);
+    }
+
+    /**
+     * Mark a component completely clean. <b>aComponent</b> will not
+     * get painted during the next paintDirtyRegions() call.
+     *
+     * @param aComponent a component
+     */
+    public void markCompletelyClean(JComponent aComponent) {
+        RepaintManager delegate = getDelegate(aComponent);
+        if (delegate != null) {
+            delegate.markCompletelyClean(aComponent);
+            return;
+        }
+        synchronized(this) {
+                dirtyComponents.remove(aComponent);
+        }
+    }
+
+    /**
+     * Convenience method that returns true if <b>aComponent</b> will be completely
+     * painted during the next paintDirtyRegions(). If computing dirty regions is
+     * expensive for your component, use this method and avoid computing dirty region
+     * if it return true.
+     *
+     * @param aComponent a component
+     * @return {@code true} if <b>aComponent</b> will be completely
+     *         painted during the next paintDirtyRegions().
+     */
+    public boolean isCompletelyDirty(JComponent aComponent) {
+        RepaintManager delegate = getDelegate(aComponent);
+        if (delegate != null) {
+            return delegate.isCompletelyDirty(aComponent);
+        }
+        Rectangle r;
+
+        r = getDirtyRegion(aComponent);
+        if(r.width == Integer.MAX_VALUE &&
+           r.height == Integer.MAX_VALUE)
+            return true;
+        else
+            return false;
+    }
+
+
+    /**
+     * Validate all of the components that have been marked invalid.
+     * @see #addInvalidComponent
+     */
+    public void validateInvalidComponents() {
+        final java.util.List<Component> ic;
+        synchronized(this) {
+            if (invalidComponents == null) {
+                return;
+            }
+            ic = invalidComponents;
+            invalidComponents = null;
+        }
+        int n = ic.size();
+        for(int i = 0; i < n; i++) {
+            final Component c = ic.get(i);
+            AccessControlContext stack = AccessController.getContext();
+            AccessControlContext acc =
+                AWTAccessor.getComponentAccessor().getAccessControlContext(c);
+            javaSecurityAccess.doIntersectionPrivilege(
+                new PrivilegedAction<Void>() {
+                    public Void run() {
+                        c.validate();
+                        return null;
+                    }
+                }, stack, acc);
+        }
+    }
+
+
+    /**
+     * This is invoked to process paint requests.  It's needed
+     * for backward compatibility in so far as RepaintManager would previously
+     * not see paint requests for top levels, so, we have to make sure
+     * a subclass correctly paints any dirty top levels.
+     */
+    private void prePaintDirtyRegions() {
+        Map<Component,Rectangle> dirtyComponents;
+        java.util.List<Runnable> runnableList;
+        synchronized(this) {
+            dirtyComponents = this.dirtyComponents;
+            runnableList = this.runnableList;
+            this.runnableList = null;
+        }
+        if (runnableList != null) {
+            for (Runnable runnable : runnableList) {
+                runnable.run();
+            }
+        }
+        paintDirtyRegions();
+        if (dirtyComponents.size() > 0) {
+            // This'll only happen if a subclass isn't correctly dealing
+            // with toplevels.
+            paintDirtyRegions(dirtyComponents);
+        }
+    }
+
+    private void updateWindows(Map<Component,Rectangle> dirtyComponents) {
+        Toolkit toolkit = Toolkit.getDefaultToolkit();
+        if (!(toolkit instanceof SunToolkit &&
+              ((SunToolkit)toolkit).needUpdateWindow()))
+        {
+            return;
+        }
+
+        Set<Window> windows = new HashSet<Window>();
+        Set<Component> dirtyComps = dirtyComponents.keySet();
+        for (Iterator<Component> it = dirtyComps.iterator(); it.hasNext();) {
+            Component dirty = it.next();
+            Window window = dirty instanceof Window ?
+                (Window)dirty :
+                SwingUtilities.getWindowAncestor(dirty);
+            if (window != null &&
+                !window.isOpaque())
+            {
+                windows.add(window);
+            }
+        }
+
+        for (Window window : windows) {
+            AWTAccessor.getWindowAccessor().updateWindow(window);
+        }
+    }
+
+    boolean isPainting() {
+        return painting;
+    }
+
+    /**
+     * Paint all of the components that have been marked dirty.
+     *
+     * @see #addDirtyRegion
+     */
+    public void paintDirtyRegions() {
+        synchronized(this) {  // swap for thread safety
+            Map<Component,Rectangle> tmp = tmpDirtyComponents;
+            tmpDirtyComponents = dirtyComponents;
+            dirtyComponents = tmp;
+            dirtyComponents.clear();
+        }
+        paintDirtyRegions(tmpDirtyComponents);
+    }
+
+    private void paintDirtyRegions(
+        final Map<Component,Rectangle> tmpDirtyComponents)
+    {
+        if (tmpDirtyComponents.isEmpty()) {
+            return;
+        }
+
+        final java.util.List<Component> roots =
+            new ArrayList<Component>(tmpDirtyComponents.size());
+        for (Component dirty : tmpDirtyComponents.keySet()) {
+            collectDirtyComponents(tmpDirtyComponents, dirty, roots);
+        }
+
+        final AtomicInteger count = new AtomicInteger(roots.size());
+        painting = true;
+        try {
+            for (int j=0 ; j < count.get(); j++) {
+                final int i = j;
+                final Component dirtyComponent = roots.get(j);
+                AccessControlContext stack = AccessController.getContext();
+                AccessControlContext acc =
+                    AWTAccessor.getComponentAccessor().getAccessControlContext(dirtyComponent);
+                javaSecurityAccess.doIntersectionPrivilege(new PrivilegedAction<Void>() {
+                    public Void run() {
+                        Rectangle rect = tmpDirtyComponents.get(dirtyComponent);
+                        // Sometimes when RepaintManager is changed during the painting
+                        // we may get null here, see #6995769 for details
+                        if (rect == null) {
+                            return null;
+                        }
+
+                        int localBoundsH = dirtyComponent.getHeight();
+                        int localBoundsW = dirtyComponent.getWidth();
+                        SwingUtilities.computeIntersection(0,
+                                                           0,
+                                                           localBoundsW,
+                                                           localBoundsH,
+                                                           rect);
+                        if (dirtyComponent instanceof JComponent) {
+                            ((JComponent)dirtyComponent).paintImmediately(
+                                rect.x,rect.y,rect.width, rect.height);
+                        }
+                        else if (dirtyComponent.isShowing()) {
+                            Graphics g = JComponent.safelyGetGraphics(
+                                    dirtyComponent, dirtyComponent);
+                            // If the Graphics goes away, it means someone disposed of
+                            // the window, don't do anything.
+                            if (g != null) {
+                                g.setClip(rect.x, rect.y, rect.width, rect.height);
+                                try {
+                                    dirtyComponent.paint(g);
+                                } finally {
+                                    g.dispose();
+                                }
+                            }
+                        }
+                        // If the repaintRoot has been set, service it now and
+                        // remove any components that are children of repaintRoot.
+                        if (repaintRoot != null) {
+                            adjustRoots(repaintRoot, roots, i + 1);
+                            count.set(roots.size());
+                            paintManager.isRepaintingRoot = true;
+                            repaintRoot.paintImmediately(0, 0, repaintRoot.getWidth(),
+                                                         repaintRoot.getHeight());
+                            paintManager.isRepaintingRoot = false;
+                            // Only service repaintRoot once.
+                            repaintRoot = null;
+                        }
+
+                        return null;
+                    }
+                }, stack, acc);
+            }
+        } finally {
+            painting = false;
+        }
+
+        updateWindows(tmpDirtyComponents);
+
+        tmpDirtyComponents.clear();
+    }
+
+
+    /**
+     * Removes any components from roots that are children of
+     * root.
+     */
+    private void adjustRoots(JComponent root,
+                             java.util.List<Component> roots, int index) {
+        for (int i = roots.size() - 1; i >= index; i--) {
+            Component c = roots.get(i);
+            for(;;) {
+                if (c == root || c == null || !(c instanceof JComponent)) {
+                    break;
+                }
+                c = c.getParent();
+            }
+            if (c == root) {
+                roots.remove(i);
+            }
+        }
+    }
+
+    Rectangle tmp = new Rectangle();
+
+    void collectDirtyComponents(Map<Component,Rectangle> dirtyComponents,
+                                Component dirtyComponent,
+                                java.util.List<Component> roots) {
+        int dx, dy, rootDx, rootDy;
+        Component component, rootDirtyComponent,parent;
+        Rectangle cBounds;
+
+        // Find the highest parent which is dirty.  When we get out of this
+        // rootDx and rootDy will contain the translation from the
+        // rootDirtyComponent's coordinate system to the coordinates of the
+        // original dirty component.  The tmp Rect is also used to compute the
+        // visible portion of the dirtyRect.
+
+        component = rootDirtyComponent = dirtyComponent;
+
+        int x = dirtyComponent.getX();
+        int y = dirtyComponent.getY();
+        int w = dirtyComponent.getWidth();
+        int h = dirtyComponent.getHeight();
+
+        dx = rootDx = 0;
+        dy = rootDy = 0;
+        tmp.setBounds(dirtyComponents.get(dirtyComponent));
+
+        // System.out.println("Collect dirty component for bound " + tmp +
+        //                                   "component bounds is " + cBounds);;
+        SwingUtilities.computeIntersection(0,0,w,h,tmp);
+
+        if (tmp.isEmpty()) {
+            // System.out.println("Empty 1");
+            return;
+        }
+
+        for(;;) {
+            if(!(component instanceof JComponent))
+                break;
+
+            parent = component.getParent();
+            if(parent == null)
+                break;
+
+            component = parent;
+
+            dx += x;
+            dy += y;
+            tmp.setLocation(tmp.x + x, tmp.y + y);
+
+            x = component.getX();
+            y = component.getY();
+            w = component.getWidth();
+            h = component.getHeight();
+            tmp = SwingUtilities.computeIntersection(0,0,w,h,tmp);
+
+            if (tmp.isEmpty()) {
+                // System.out.println("Empty 2");
+                return;
+            }
+
+            if (dirtyComponents.get(component) != null) {
+                rootDirtyComponent = component;
+                rootDx = dx;
+                rootDy = dy;
+            }
+        }
+
+        if (dirtyComponent != rootDirtyComponent) {
+            Rectangle r;
+            tmp.setLocation(tmp.x + rootDx - dx,
+                            tmp.y + rootDy - dy);
+            r = dirtyComponents.get(rootDirtyComponent);
+            SwingUtilities.computeUnion(tmp.x,tmp.y,tmp.width,tmp.height,r);
+        }
+
+        // If we haven't seen this root before, then we need to add it to the
+        // list of root dirty Views.
+
+        if (!roots.contains(rootDirtyComponent))
+            roots.add(rootDirtyComponent);
+    }
+
+
+    /**
+     * Returns a string that displays and identifies this
+     * object's properties.
+     *
+     * @return a String representation of this object
+     */
+    public synchronized String toString() {
+        StringBuilder sb = new StringBuilder();
+        if(dirtyComponents != null)
+            sb.append("" + dirtyComponents);
+        return sb.toString();
+    }
+
+
+    /**
+     * Return the offscreen buffer that should be used as a double buffer with
+     * the component <code>c</code>.
+     * By default there is a double buffer per RepaintManager.
+     * The buffer might be smaller than <code>(proposedWidth,proposedHeight)</code>
+     * This happens when the maximum double buffer size as been set for the receiving
+     * repaint manager.
+     *
+     * @param c the component
+     * @param proposedWidth the width of the buffer
+     * @param proposedHeight the height of the buffer
+     *
+     * @return the image
+     */
+    public Image getOffscreenBuffer(Component c,int proposedWidth,int proposedHeight) {
+        RepaintManager delegate = getDelegate(c);
+        if (delegate != null) {
+            return delegate.getOffscreenBuffer(c, proposedWidth, proposedHeight);
+        }
+        return _getOffscreenBuffer(c, proposedWidth, proposedHeight);
+    }
+
+    /**
+     * Return a volatile offscreen buffer that should be used as a
+     * double buffer with the specified component <code>c</code>.
+     * The image returned will be an instance of VolatileImage, or null
+     * if a VolatileImage object could not be instantiated.
+     * This buffer might be smaller than <code>(proposedWidth,proposedHeight)</code>.
+     * This happens when the maximum double buffer size has been set for this
+     * repaint manager.
+     *
+     * @param c the component
+     * @param proposedWidth the width of the buffer
+     * @param proposedHeight the height of the buffer
+     *
+     * @return the volatile image
+     * @see java.awt.image.VolatileImage
+     * @since 1.4
+     */
+    public Image getVolatileOffscreenBuffer(Component c,
+                                            int proposedWidth,int proposedHeight) {
+        RepaintManager delegate = getDelegate(c);
+        if (delegate != null) {
+            return delegate.getVolatileOffscreenBuffer(c, proposedWidth,
+                                                        proposedHeight);
+        }
+
+        // If the window is non-opaque, it's double-buffered at peer's level
+        Window w = (c instanceof Window) ? (Window)c : SwingUtilities.getWindowAncestor(c);
+        if (!w.isOpaque()) {
+            Toolkit tk = Toolkit.getDefaultToolkit();
+            if ((tk instanceof SunToolkit) && (((SunToolkit)tk).needUpdateWindow())) {
+                return null;
+            }
+        }
+
+        GraphicsConfiguration config = c.getGraphicsConfiguration();
+        if (config == null) {
+            config = GraphicsEnvironment.getLocalGraphicsEnvironment().
+                            getDefaultScreenDevice().getDefaultConfiguration();
+        }
+        Dimension maxSize = getDoubleBufferMaximumSize();
+        int width = proposedWidth < 1 ? 1 :
+            (proposedWidth > maxSize.width? maxSize.width : proposedWidth);
+        int height = proposedHeight < 1 ? 1 :
+            (proposedHeight > maxSize.height? maxSize.height : proposedHeight);
+        VolatileImage image = volatileMap.get(config);
+        if (image == null || image.getWidth() < width ||
+                             image.getHeight() < height) {
+            if (image != null) {
+                image.flush();
+            }
+            image = config.createCompatibleVolatileImage(width, height,
+                                                         volatileBufferType);
+            volatileMap.put(config, image);
+        }
+        return image;
+    }
+
+    private Image _getOffscreenBuffer(Component c, int proposedWidth, int proposedHeight) {
+        Dimension maxSize = getDoubleBufferMaximumSize();
+        DoubleBufferInfo doubleBuffer;
+        int width, height;
+
+        // If the window is non-opaque, it's double-buffered at peer's level
+        Window w = (c instanceof Window) ? (Window)c : SwingUtilities.getWindowAncestor(c);
+        if (!w.isOpaque()) {
+            Toolkit tk = Toolkit.getDefaultToolkit();
+            if ((tk instanceof SunToolkit) && (((SunToolkit)tk).needUpdateWindow())) {
+                return null;
+            }
+        }
+
+        if (standardDoubleBuffer == null) {
+            standardDoubleBuffer = new DoubleBufferInfo();
+        }
+        doubleBuffer = standardDoubleBuffer;
+
+        width = proposedWidth < 1? 1 :
+                  (proposedWidth > maxSize.width? maxSize.width : proposedWidth);
+        height = proposedHeight < 1? 1 :
+                  (proposedHeight > maxSize.height? maxSize.height : proposedHeight);
+
+        if (doubleBuffer.needsReset || (doubleBuffer.image != null &&
+                                        (doubleBuffer.size.width < width ||
+                                         doubleBuffer.size.height < height))) {
+            doubleBuffer.needsReset = false;
+            if (doubleBuffer.image != null) {
+                doubleBuffer.image.flush();
+                doubleBuffer.image = null;
+            }
+            width = Math.max(doubleBuffer.size.width, width);
+            height = Math.max(doubleBuffer.size.height, height);
+        }
+
+        Image result = doubleBuffer.image;
+
+        if (doubleBuffer.image == null) {
+            result = c.createImage(width , height);
+            doubleBuffer.size = new Dimension(width, height);
+            if (c instanceof JComponent) {
+                ((JComponent)c).setCreatedDoubleBuffer(true);
+                doubleBuffer.image = result;
+            }
+            // JComponent will inform us when it is no longer valid
+            // (via removeNotify) we have no such hook to other components,
+            // therefore we don't keep a ref to the Component
+            // (indirectly through the Image) by stashing the image.
+        }
+        return result;
+    }
+
+
+    /**
+     * Set the maximum double buffer size.
+     *
+     * @param d the dimension
+     */
+    public void setDoubleBufferMaximumSize(Dimension d) {
+        doubleBufferMaxSize = d;
+        if (doubleBufferMaxSize == null) {
+            clearImages();
+        } else {
+            clearImages(d.width, d.height);
+        }
+    }
+
+    private void clearImages() {
+        clearImages(0, 0);
+    }
+
+    private void clearImages(int width, int height) {
+        if (standardDoubleBuffer != null && standardDoubleBuffer.image != null) {
+            if (standardDoubleBuffer.image.getWidth(null) > width ||
+                standardDoubleBuffer.image.getHeight(null) > height) {
+                standardDoubleBuffer.image.flush();
+                standardDoubleBuffer.image = null;
+            }
+        }
+        // Clear out the VolatileImages
+        Iterator<GraphicsConfiguration> gcs = volatileMap.keySet().iterator();
+        while (gcs.hasNext()) {
+            GraphicsConfiguration gc = gcs.next();
+            VolatileImage image = volatileMap.get(gc);
+            if (image.getWidth() > width || image.getHeight() > height) {
+                image.flush();
+                gcs.remove();
+            }
+        }
+    }
+
+    /**
+     * Returns the maximum double buffer size.
+     *
+     * @return a Dimension object representing the maximum size
+     */
+    public Dimension getDoubleBufferMaximumSize() {
+        if (doubleBufferMaxSize == null) {
+            try {
+                Rectangle virtualBounds = new Rectangle();
+                GraphicsEnvironment ge = GraphicsEnvironment.
+                                                 getLocalGraphicsEnvironment();
+                for (GraphicsDevice gd : ge.getScreenDevices()) {
+                    GraphicsConfiguration gc = gd.getDefaultConfiguration();
+                    virtualBounds = virtualBounds.union(gc.getBounds());
+                }
+                doubleBufferMaxSize = new Dimension(virtualBounds.width,
+                                                    virtualBounds.height);
+            } catch (HeadlessException e) {
+                doubleBufferMaxSize = new Dimension(Integer.MAX_VALUE, Integer.MAX_VALUE);
+            }
+        }
+        return doubleBufferMaxSize;
+    }
+
+    /**
+     * Enables or disables double buffering in this RepaintManager.
+     * CAUTION: The default value for this property is set for optimal
+     * paint performance on the given platform and it is not recommended
+     * that programs modify this property directly.
+     *
+     * @param aFlag  true to activate double buffering
+     * @see #isDoubleBufferingEnabled
+     */
+    public void setDoubleBufferingEnabled(boolean aFlag) {
+        doubleBufferingEnabled = aFlag;
+        PaintManager paintManager = getPaintManager();
+        if (!aFlag && paintManager.getClass() != PaintManager.class) {
+            setPaintManager(new PaintManager());
+        }
+    }
+
+    /**
+     * Returns true if this RepaintManager is double buffered.
+     * The default value for this property may vary from platform
+     * to platform.  On platforms where native double buffering
+     * is supported in the AWT, the default value will be <code>false</code>
+     * to avoid unnecessary buffering in Swing.
+     * On platforms where native double buffering is not supported,
+     * the default value will be <code>true</code>.
+     *
+     * @return true if this object is double buffered
+     */
+    public boolean isDoubleBufferingEnabled() {
+        return doubleBufferingEnabled;
+    }
+
+    /**
+     * This resets the double buffer. Actually, it marks the double buffer
+     * as invalid, the double buffer will then be recreated on the next
+     * invocation of getOffscreenBuffer.
+     */
+    void resetDoubleBuffer() {
+        if (standardDoubleBuffer != null) {
+            standardDoubleBuffer.needsReset = true;
+        }
+    }
+
+    /**
+     * This resets the volatile double buffer.
+     */
+    void resetVolatileDoubleBuffer(GraphicsConfiguration gc) {
+        Image image = volatileMap.remove(gc);
+        if (image != null) {
+            image.flush();
+        }
+    }
+
+    /**
+     * Returns true if we should use the <code>Image</code> returned
+     * from <code>getVolatileOffscreenBuffer</code> to do double buffering.
+     */
+    boolean useVolatileDoubleBuffer() {
+        return volatileImageBufferEnabled;
+    }
+
+    /**
+     * Returns true if the current thread is the thread painting.  This
+     * will return false if no threads are painting.
+     */
+    private synchronized boolean isPaintingThread() {
+        return (Thread.currentThread() == paintThread);
+    }
+    //
+    // Paint methods.  You very, VERY rarely need to invoke these.
+    // They are invoked directly from JComponent's painting code and
+    // when painting happens outside the normal flow: DefaultDesktopManager
+    // and JViewport.  If you end up needing these methods in other places be
+    // careful that you don't get stuck in a paint loop.
+    //
+
+    /**
+     * Paints a region of a component
+     *
+     * @param paintingComponent Component to paint
+     * @param bufferComponent Component to obtain buffer for
+     * @param g Graphics to paint to
+     * @param x X-coordinate
+     * @param y Y-coordinate
+     * @param w Width
+     * @param h Height
+     */
+    void paint(JComponent paintingComponent,
+               JComponent bufferComponent, Graphics g,
+               int x, int y, int w, int h) {
+        PaintManager paintManager = getPaintManager();
+        if (!isPaintingThread()) {
+            // We're painting to two threads at once.  PaintManager deals
+            // with this a bit better than BufferStrategyPaintManager, use
+            // it to avoid possible exceptions/corruption.
+            if (paintManager.getClass() != PaintManager.class) {
+                paintManager = new PaintManager();
+                paintManager.repaintManager = this;
+            }
+        }
+        if (!paintManager.paint(paintingComponent, bufferComponent, g,
+                                x, y, w, h)) {
+            g.setClip(x, y, w, h);
+            paintingComponent.paintToOffscreen(g, x, y, w, h, x + w, y + h);
+        }
+    }
+
+    /**
+     * Does a copy area on the specified region.
+     *
+     * @param clip Whether or not the copyArea needs to be clipped to the
+     *             Component's bounds.
+     */
+    void copyArea(JComponent c, Graphics g, int x, int y, int w, int h,
+                  int deltaX, int deltaY, boolean clip) {
+        getPaintManager().copyArea(c, g, x, y, w, h, deltaX, deltaY, clip);
+    }
+
+    private java.util.List<RepaintListener> repaintListeners = new ArrayList<>(1);
+
+    private void addRepaintListener(RepaintListener l) {
+        repaintListeners.add(l);
+    }
+
+    private void removeRepaintListener(RepaintListener l) {
+        repaintListeners.remove(l);
+    }
+
+    /**
+     * Notify the attached repaint listeners that an area of the {@code c} component
+     * has been immediately repainted, that is without scheduling a repaint runnable,
+     * due to performing a "blit" (via calling the {@code copyArea} method).
+     *
+     * @param c the component
+     * @param x the x coordinate of the area
+     * @param y the y coordinate of the area
+     * @param w the width of the area
+     * @param h the height of the area
+     */
+    void notifyRepaintPerformed(JComponent c, int x, int y, int w, int h) {
+        for (RepaintListener l : repaintListeners) {
+            l.repaintPerformed(c, x, y, w, h);
+        }
+    }
+
+    /**
+     * Invoked prior to any paint/copyArea method calls.  This will
+     * be followed by an invocation of <code>endPaint</code>.
+     * <b>WARNING</b>: Callers of this method need to wrap the call
+     * in a <code>try/finally</code>, otherwise if an exception is thrown
+     * during the course of painting the RepaintManager may
+     * be left in a state in which the screen is not updated, eg:
+     * <pre>
+     * repaintManager.beginPaint();
+     * try {
+     *   repaintManager.paint(...);
+     * } finally {
+     *   repaintManager.endPaint();
+     * }
+     * </pre>
+     */
+    void beginPaint() {
+        boolean multiThreadedPaint = false;
+        int paintDepth;
+        Thread currentThread = Thread.currentThread();
+        synchronized(this) {
+            paintDepth = this.paintDepth;
+            if (paintThread == null || currentThread == paintThread) {
+                paintThread = currentThread;
+                this.paintDepth++;
+            } else {
+                multiThreadedPaint = true;
+            }
+        }
+        if (!multiThreadedPaint && paintDepth == 0) {
+            getPaintManager().beginPaint();
+        }
+    }
+
+    /**
+     * Invoked after <code>beginPaint</code> has been invoked.
+     */
+    void endPaint() {
+        if (isPaintingThread()) {
+            PaintManager paintManager = null;
+            synchronized(this) {
+                if (--paintDepth == 0) {
+                    paintManager = getPaintManager();
+                }
+            }
+            if (paintManager != null) {
+                paintManager.endPaint();
+                synchronized(this) {
+                    paintThread = null;
+                }
+            }
+        }
+    }
+
+    /**
+     * If possible this will show a previously rendered portion of
+     * a Component.  If successful, this will return true, otherwise false.
+     * <p>
+     * WARNING: This method is invoked from the native toolkit thread, be
+     * very careful as to what methods this invokes!
+     */
+    boolean show(Container c, int x, int y, int w, int h) {
+        return getPaintManager().show(c, x, y, w, h);
+    }
+
+    /**
+     * Invoked when the doubleBuffered or useTrueDoubleBuffering
+     * properties of a JRootPane change.  This may come in on any thread.
+     */
+    void doubleBufferingChanged(JRootPane rootPane) {
+        getPaintManager().doubleBufferingChanged(rootPane);
+    }
+
+    /**
+     * Sets the <code>PaintManager</code> that is used to handle all
+     * double buffered painting.
+     *
+     * @param paintManager The PaintManager to use.  Passing in null indicates
+     *        the fallback PaintManager should be used.
+     */
+    void setPaintManager(PaintManager paintManager) {
+        if (paintManager == null) {
+            paintManager = new PaintManager();
+        }
+        PaintManager oldPaintManager;
+        synchronized(this) {
+            oldPaintManager = this.paintManager;
+            this.paintManager = paintManager;
+            paintManager.repaintManager = this;
+        }
+        if (oldPaintManager != null) {
+            oldPaintManager.dispose();
+        }
+    }
+
+    private synchronized PaintManager getPaintManager() {
+        if (paintManager == null) {
+            PaintManager paintManager = null;
+            if (doubleBufferingEnabled && !nativeDoubleBuffering) {
+                switch (bufferStrategyType) {
+                case BUFFER_STRATEGY_NOT_SPECIFIED:
+                    Toolkit tk = Toolkit.getDefaultToolkit();
+                    if (tk instanceof SunToolkit) {
+                        SunToolkit stk = (SunToolkit) tk;
+                        if (stk.useBufferPerWindow()) {
+                            paintManager = new BufferStrategyPaintManager();
+                        }
+                    }
+                    break;
+                case BUFFER_STRATEGY_SPECIFIED_ON:
+                    paintManager = new BufferStrategyPaintManager();
+                    break;
+                default:
+                    break;
+                }
+            }
+            // null case handled in setPaintManager
+            setPaintManager(paintManager);
+        }
+        return paintManager;
+    }
+
+    private void scheduleProcessingRunnable(AppContext context) {
+        if (processingRunnable.markPending()) {
+            Toolkit tk = Toolkit.getDefaultToolkit();
+            if (tk instanceof SunToolkit) {
+                SunToolkit.getSystemEventQueueImplPP(context).
+                  postEvent(new InvocationEvent(Toolkit.getDefaultToolkit(),
+                                                processingRunnable));
+            } else {
+                Toolkit.getDefaultToolkit().getSystemEventQueue().
+                      postEvent(new InvocationEvent(Toolkit.getDefaultToolkit(),
+                                                    processingRunnable));
+            }
+        }
+    }
+
+
+    /**
+     * PaintManager is used to handle all double buffered painting for
+     * Swing.  Subclasses should call back into the JComponent method
+     * <code>paintToOffscreen</code> to handle the actual painting.
+     */
+    static class PaintManager {
+        /**
+         * RepaintManager the PaintManager has been installed on.
+         */
+        protected RepaintManager repaintManager;
+        boolean isRepaintingRoot;
+
+        /**
+         * Paints a region of a component
+         *
+         * @param paintingComponent Component to paint
+         * @param bufferComponent Component to obtain buffer for
+         * @param g Graphics to paint to
+         * @param x X-coordinate
+         * @param y Y-coordinate
+         * @param w Width
+         * @param h Height
+         * @return true if painting was successful.
+         */
+        public boolean paint(JComponent paintingComponent,
+                             JComponent bufferComponent, Graphics g,
+                             int x, int y, int w, int h) {
+            // First attempt to use VolatileImage buffer for performance.
+            // If this fails (which should rarely occur), fallback to a
+            // standard Image buffer.
+            boolean paintCompleted = false;
+            Image offscreen;
+            int sw = w + 1;
+            int sh = h + 1;
+
+            if (repaintManager.useVolatileDoubleBuffer() &&
+                (offscreen = getValidImage(repaintManager.
+                getVolatileOffscreenBuffer(bufferComponent, sw, sh))) != null) {
+                VolatileImage vImage = (java.awt.image.VolatileImage)offscreen;
+                GraphicsConfiguration gc = bufferComponent.
+                                            getGraphicsConfiguration();
+                for (int i = 0; !paintCompleted &&
+                         i < RepaintManager.VOLATILE_LOOP_MAX; i++) {
+                    if (vImage.validate(gc) ==
+                                   VolatileImage.IMAGE_INCOMPATIBLE) {
+                        repaintManager.resetVolatileDoubleBuffer(gc);
+                        offscreen = repaintManager.getVolatileOffscreenBuffer(
+                            bufferComponent, sw, sh);
+                        vImage = (java.awt.image.VolatileImage)offscreen;
+                    }
+                    paintDoubleBuffered(paintingComponent, vImage, g, x, y,
+                                        w, h);
+                    paintCompleted = !vImage.contentsLost();
+                }
+            }
+            // VolatileImage painting loop failed, fallback to regular
+            // offscreen buffer
+            if (!paintCompleted && (offscreen = getValidImage(
+                      repaintManager.getOffscreenBuffer(
+                      bufferComponent, w, h))) != null) {
+                paintDoubleBuffered(paintingComponent, offscreen, g, x, y, w,
+                                    h);
+                paintCompleted = true;
+            }
+            return paintCompleted;
+        }
+
+        /**
+         * Does a copy area on the specified region.
+         */
+        public void copyArea(JComponent c, Graphics g, int x, int y, int w,
+                             int h, int deltaX, int deltaY, boolean clip) {
+            g.copyArea(x, y, w, h, deltaX, deltaY);
+        }
+
+        /**
+         * Invoked prior to any calls to paint or copyArea.
+         */
+        public void beginPaint() {
+        }
+
+        /**
+         * Invoked to indicate painting has been completed.
+         */
+        public void endPaint() {
+        }
+
+        /**
+         * Shows a region of a previously rendered component.  This
+         * will return true if successful, false otherwise.  The default
+         * implementation returns false.
+         */
+        public boolean show(Container c, int x, int y, int w, int h) {
+            return false;
+        }
+
+        /**
+         * Invoked when the doubleBuffered or useTrueDoubleBuffering
+         * properties of a JRootPane change.  This may come in on any thread.
+         */
+        public void doubleBufferingChanged(JRootPane rootPane) {
+        }
+
+        /**
+         * Paints a portion of a component to an offscreen buffer.
+         */
+        protected void paintDoubleBuffered(JComponent c, Image image,
+                Graphics g, int clipX, int clipY,
+                int clipW, int clipH) {
+            if (image instanceof VolatileImage && isPixelsCopying(c, g)) {
+                paintDoubleBufferedFPScales(c, image, g, clipX, clipY, clipW, clipH);
+            } else {
+                paintDoubleBufferedImpl(c, image, g, clipX, clipY, clipW, clipH);
+            }
+        }
+
+        private void paintDoubleBufferedImpl(JComponent c, Image image,
+                                             Graphics g, int clipX, int clipY,
+                                             int clipW, int clipH) {
+            Graphics osg = image.getGraphics();
+            int bw = Math.min(clipW, image.getWidth(null));
+            int bh = Math.min(clipH, image.getHeight(null));
+            int x,y,maxx,maxy;
+
+            try {
+                for(x = clipX, maxx = clipX+clipW; x < maxx ;  x += bw ) {
+                    for(y=clipY, maxy = clipY + clipH; y < maxy ; y += bh) {
+                        osg.translate(-x, -y);
+                        osg.setClip(x,y,bw,bh);
+                        if (volatileBufferType != Transparency.OPAQUE
+                                && osg instanceof Graphics2D) {
+                            final Graphics2D g2d = (Graphics2D) osg;
+                            final Color oldBg = g2d.getBackground();
+                            g2d.setBackground(c.getBackground());
+                            g2d.clearRect(x, y, bw, bh);
+                            g2d.setBackground(oldBg);
+                        }
+                        c.paintToOffscreen(osg, x, y, bw, bh, maxx, maxy);
+                        g.setClip(x, y, bw, bh);
+                        if (volatileBufferType != Transparency.OPAQUE
+                                && g instanceof Graphics2D) {
+                            final Graphics2D g2d = (Graphics2D) g;
+                            final Composite oldComposite = g2d.getComposite();
+                            g2d.setComposite(AlphaComposite.Src);
+                            g2d.drawImage(image, x, y, c);
+                            g2d.setComposite(oldComposite);
+                        } else {
+                            g.drawImage(image, x, y, c);
+                        }
+                        osg.translate(x, y);
+                    }
+                }
+            } finally {
+                osg.dispose();
+            }
+        }
+
+        private void paintDoubleBufferedFPScales(JComponent c, Image image,
+                                                 Graphics g, int clipX, int clipY,
+                                                 int clipW, int clipH) {
+            Graphics osg = image.getGraphics();
+            Graphics2D g2d = (Graphics2D) g;
+            Graphics2D osg2d = (Graphics2D) osg;
+
+            AffineTransform identity = new AffineTransform();
+            int bw = Math.min(clipW, image.getWidth(null));
+            int bh = Math.min(clipH, image.getHeight(null));
+            int x, y, maxx, maxy;
+
+            AffineTransform tx = g2d.getTransform();
+            double scaleX = tx.getScaleX();
+            double scaleY = tx.getScaleY();
+            double trX = tx.getTranslateX();
+            double trY = tx.getTranslateY();
+
+            boolean translucent = volatileBufferType != Transparency.OPAQUE;
+            Composite oldComposite = g2d.getComposite();
+
+            try {
+                for (x = clipX, maxx = clipX + clipW; x < maxx; x += bw) {
+                    for (y = clipY, maxy = clipY + clipH; y < maxy; y += bh) {
+
+                        // draw x, y, bw, bh
+                        int pixelx1 = Region.clipRound(x * scaleX + trX);
+                        int pixely1 = Region.clipRound(y * scaleY + trY);
+                        int pixelx2 = Region.clipRound((x + bw) * scaleX + trX);
+                        int pixely2 = Region.clipRound((y + bh) * scaleY + trY);
+                        int pixelw = pixelx2 - pixelx1;
+                        int pixelh = pixely2 - pixely1;
+
+                        osg2d.setTransform(identity);
+                        if (translucent) {
+                            final Color oldBg = g2d.getBackground();
+                            g2d.setBackground(c.getBackground());
+                            g2d.clearRect(pixelx1, pixely1, pixelw, pixelh);
+                            g2d.setBackground(oldBg);
+                        }
+
+                        osg2d.setClip(0, 0, pixelw, pixelh);
+                        osg2d.translate(trX - pixelx1, trY - pixely1);
+                        osg2d.scale(scaleX, scaleY);
+                        c.paintToOffscreen(osg, x, y, bw, bh, maxx, maxy);
+
+                        g2d.setTransform(identity);
+                        g2d.setClip(pixelx1, pixely1, pixelw, pixelh);
+                        AffineTransform stx = new AffineTransform();
+                        stx.translate(pixelx1, pixely1);
+                        stx.scale(scaleX, scaleY);
+                        g2d.setTransform(stx);
+
+                        if (translucent) {
+                            g2d.setComposite(AlphaComposite.Src);
+                        }
+
+                        g2d.drawImage(image, 0, 0, c);
+
+                        if (translucent) {
+                            g2d.setComposite(oldComposite);
+                        }
+                        g2d.setTransform(tx);
+                    }
+                }
+            } finally {
+                osg.dispose();
+            }
+        }
+
+        /**
+         * If <code>image</code> is non-null with a positive size it
+         * is returned, otherwise null is returned.
+         */
+        private Image getValidImage(Image image) {
+            if (image != null && image.getWidth(null) > 0 &&
+                                 image.getHeight(null) > 0) {
+                return image;
+            }
+            return null;
+        }
+
+        /**
+         * Schedules a repaint for the specified component.  This differs
+         * from <code>root.repaint</code> in that if the RepaintManager is
+         * currently processing paint requests it'll process this request
+         * with the current set of requests.
+         */
+        protected void repaintRoot(JComponent root) {
+            assert (repaintManager.repaintRoot == null);
+            if (repaintManager.painting) {
+                repaintManager.repaintRoot = root;
+            }
+            else {
+                root.repaint();
+            }
+        }
+
+        /**
+         * Returns true if the component being painted is the root component
+         * that was previously passed to <code>repaintRoot</code>.
+         */
+        protected boolean isRepaintingRoot() {
+            return isRepaintingRoot;
+        }
+
+        /**
+         * Cleans up any state.  After invoked the PaintManager will no
+         * longer be used anymore.
+         */
+        protected void dispose() {
+        }
+
+        private boolean isPixelsCopying(JComponent c, Graphics g) {
+
+            AffineTransform tx = getTransform(g);
+            GraphicsConfiguration gc = c.getGraphicsConfiguration();
+
+            if (tx == null || gc == null
+                    || !SwingUtilities2.isFloatingPointScale(tx)) {
+                return false;
+            }
+
+            AffineTransform gcTx = gc.getDefaultTransform();
+
+            return gcTx.getScaleX() == tx.getScaleX()
+                    && gcTx.getScaleY() == tx.getScaleY();
+        }
+
+        private static AffineTransform getTransform(Graphics g) {
+            if (g instanceof SunGraphics2D) {
+                return ((SunGraphics2D) g).transform;
+            } else if (g instanceof Graphics2D) {
+                return ((Graphics2D) g).getTransform();
+            }
+            return null;
+        }
+    }
+
+    private class DoubleBufferInfo {
+        public Image image;
+        public Dimension size;
+        public boolean needsReset = false;
+    }
+
+
+    /**
+     * Listener installed to detect display changes. When display changes,
+     * schedules a callback to notify all RepaintManagers of the display
+     * changes. Only one DisplayChangedHandler is ever installed. The
+     * singleton instance will schedule notification for all AppContexts.
+     */
+    private static final class DisplayChangedHandler implements
+                                             DisplayChangedListener {
+        // Empty non private constructor was added because access to this
+        // class shouldn't be generated by the compiler using synthetic
+        // accessor method
+        DisplayChangedHandler() {
+        }
+
+        public void displayChanged() {
+            scheduleDisplayChanges();
+        }
+
+        public void paletteChanged() {
+        }
+
+        private static void scheduleDisplayChanges() {
+            // To avoid threading problems, we notify each RepaintManager
+            // on the thread it was created on.
+            for (AppContext context : AppContext.getAppContexts()) {
+                synchronized(context) {
+                    if (!context.isDisposed()) {
+                        EventQueue eventQueue = (EventQueue)context.get(
+                            AppContext.EVENT_QUEUE_KEY);
+                        if (eventQueue != null) {
+                            eventQueue.postEvent(new InvocationEvent(
+                                Toolkit.getDefaultToolkit(),
+                                new DisplayChangedRunnable()));
+                        }
+                    }
+                }
+            }
+        }
+    }
+
+
+    private static final class DisplayChangedRunnable implements Runnable {
+        public void run() {
+            RepaintManager.currentManager((JComponent)null).displayChanged();
+        }
+    }
+
+
+    /**
+     * Runnable used to process all repaint/revalidate requests.
+     */
+    private final class ProcessingRunnable implements Runnable {
+        // If true, we're wainting on the EventQueue.
+        private boolean pending;
+
+        /**
+         * Marks this processing runnable as pending. If this was not
+         * already marked as pending, true is returned.
+         */
+        public synchronized boolean markPending() {
+            if (!pending) {
+                pending = true;
+                return true;
+            }
+            return false;
+        }
+
+        public void run() {
+            synchronized (this) {
+                pending = false;
+            }
+            // First pass, flush any heavy paint events into real paint
+            // events.  If there are pending heavy weight requests this will
+            // result in q'ing this request up one more time.  As
+            // long as no other requests come in between now and the time
+            // the second one is processed nothing will happen.  This is not
+            // ideal, but the logic needed to suppress the second request is
+            // more headache than it's worth.
+            scheduleHeavyWeightPaints();
+            // Do the actual validation and painting.
+            validateInvalidComponents();
+            prePaintDirtyRegions();
+        }
+    }
+    private RepaintManager getDelegate(Component c) {
+        RepaintManager delegate = SwingUtilities3.getDelegateRepaintManager(c);
+        if (this == delegate) {
+            delegate = null;
+        }
+        return delegate;
+    }
+}