8280482: Window transparency bug on Linux

Reviewed-by: dnguyen, azvegint

src/java.desktop/unix/classes/sun/awt/X11/XWindowPeer.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2002, 2021, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2002, 2023, 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
@@ -804,10 +804,10 @@ public void handleConfigureNotifyEvent(XEvent xev) {
         if (insLog.isLoggable(PlatformLogger.Level.FINE)) {
             insLog.fine(xe.toString());
         }
-        checkIfOnNewScreen(toGlobal(new Rectangle(scaleDown(xe.get_x()),
+        checkIfOnNewScreen(new Rectangle(scaleDown(xe.get_x()),
                 scaleDown(xe.get_y()),
                 scaleDown(xe.get_width()),
-                scaleDown(xe.get_height()))));
+                scaleDown(xe.get_height())));
 
         Rectangle oldBounds = getBounds();
 

test/jdk/java/awt/Multiscreen/MultiScreenCheckScreenIDTest.java

@@ -0,0 +1,148 @@
+/*
+ * Copyright (c) 2023, 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.
+ *
+ * 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.
+ */
+
+import java.awt.AWTException;
+import java.awt.Color;
+import java.awt.GraphicsDevice;
+import java.awt.GraphicsEnvironment;
+import java.awt.Rectangle;
+import java.awt.Robot;
+import java.awt.Window;
+
+import javax.swing.JWindow;
+import javax.swing.SwingUtilities;
+
+import java.awt.event.MouseAdapter;
+import java.awt.event.MouseEvent;
+import java.lang.reflect.InvocationTargetException;
+import java.util.ArrayList;
+import java.util.List;
+
+/*
+ * @test
+ * @bug 8280482
+ * @key headful
+ * @summary Test to check if window GC doesn't change within same screen.
+ * @run main MultiScreenCheckScreenIDTest
+ */
+
+public class MultiScreenCheckScreenIDTest extends MouseAdapter {
+    private static final int COLS = 12;
+    private static final int ROWS = 8;
+    private static final Color BACKGROUND = new Color(0, 0, 255, 64);
+    private static GraphicsDevice[] screens;
+    static List<Window> windowList = new ArrayList<>();
+    static Robot robot;
+    static JWindow window;
+
+
+    public static void main(final String[] args) throws Exception {
+        try {
+            createGUI();
+        } finally {
+            for (Window win : windowList) {
+                win.dispose();
+            }
+            if (window != null) {
+                window.dispose();
+            }
+        }
+        System.out.println("Test Pass");
+    }
+
+    private static void createGUI() throws AWTException {
+        new MultiScreenCheckScreenIDTest().createWindowGrid();
+    }
+
+    private void createWindowGrid() throws AWTException {
+        screens = GraphicsEnvironment
+                .getLocalGraphicsEnvironment()
+                .getScreenDevices();
+
+        if (screens.length < 2) {
+            System.out.println("Testing aborted. Required min of 2 screens. " +
+                    "Available : " + screens.length);
+            return;
+        }
+        robot = new Robot();
+
+        int screenNumber = 1;
+        for (GraphicsDevice screen : screens) {
+            Rectangle screenBounds = screen.getDefaultConfiguration().getBounds();
+
+            for (Rectangle r : gridOfRectangles(screenBounds, COLS, ROWS)) {
+                try {
+                    SwingUtilities.invokeAndWait(() -> {
+                        try {
+                            window = createWindow(r);
+                        } catch (Exception e) {
+                            throw new RuntimeException(e);
+                        }
+                    });
+                } catch (InterruptedException | InvocationTargetException e) {
+                    e.printStackTrace();
+                }
+                robot.delay(50);
+                robot.waitForIdle();
+                if (window.getBounds().intersects(screenBounds)) {
+                    if (!(window.getGraphicsConfiguration().getBounds().
+                            intersects(screenBounds))) {
+                        throw new RuntimeException("Graphics configuration " +
+                                "changed for screen :" + screenNumber);
+                    }
+                }
+                windowList.add(window);
+            }
+            screenNumber++;
+        }
+    }
+
+    private JWindow createWindow(Rectangle bounds) {
+        JWindow window = new JWindow();
+        window.setBounds(bounds);
+        window.setBackground(BACKGROUND);
+        window.setAlwaysOnTop(true);
+        window.addMouseListener(this);
+        window.setVisible(true);
+        return window;
+    }
+
+    @Override
+    public void mouseClicked(MouseEvent e) {
+        ((Window) e.getSource()).dispose();
+    }
+
+    private static List<Rectangle> gridOfRectangles(Rectangle r, int cols, int rows) {
+        List<Rectangle> l = new ArrayList<>();
+        for (int row = 0; row < rows; row++) {
+            int y1 = r.y + (int) Math.round(r.height * (double) row / rows);
+            int y2 = r.y + (int) Math.round(r.height * (double) (row + 1) / rows);
+            for (int col = 0; col < cols; col++) {
+                int x1 = r.x + (int) Math.round(r.width * (double) col / cols);
+                int x2 = r.x + (int) Math.round(r.width * (double) (col + 1) / cols);
+                l.add(new Rectangle(x1, y1, x2 - x1, y2 - y1));
+            }
+        }
+        return l;
+    }
+}