Backport 651ac3cc0f2a8b3edf5cddb42df1d38d4aa0e1a6

Author: duke

src/java.desktop/windows/native/libawt/windows/awt_Toolkit.cpp

@@ -2036,28 +2036,13 @@ JNIEnv* AwtToolkit::GetEnv() {
 
 BOOL AwtToolkit::GetScreenInsets(int screenNum, RECT * rect)
 {
-    /* if primary display */
-    if (screenNum == 0) {
-        RECT rRW;
-        if (::SystemParametersInfo(SPI_GETWORKAREA,0,(void *) &rRW,0) == TRUE) {
-            rect->top = rRW.top;
-            rect->left = rRW.left;
-            rect->bottom = ::GetSystemMetrics(SM_CYSCREEN) - rRW.bottom;
-            rect->right = ::GetSystemMetrics(SM_CXSCREEN) - rRW.right;
-            return TRUE;
-        }
-    }
-    /* if additional display */
-    else {
-        MONITORINFO *miInfo;
-        miInfo = AwtWin32GraphicsDevice::GetMonitorInfo(screenNum);
-        if (miInfo) {
-            rect->top = miInfo->rcWork.top    - miInfo->rcMonitor.top;
-            rect->left = miInfo->rcWork.left   - miInfo->rcMonitor.left;
-            rect->bottom = miInfo->rcMonitor.bottom - miInfo->rcWork.bottom;
-            rect->right = miInfo->rcMonitor.right - miInfo->rcWork.right;
-            return TRUE;
-        }
+    MONITORINFO *miInfo = AwtWin32GraphicsDevice::GetMonitorInfo(screenNum);
+    if (miInfo) {
+        rect->top = miInfo->rcWork.top - miInfo->rcMonitor.top;
+        rect->left = miInfo->rcWork.left - miInfo->rcMonitor.left;
+        rect->bottom = miInfo->rcMonitor.bottom - miInfo->rcWork.bottom;
+        rect->right = miInfo->rcMonitor.right - miInfo->rcWork.right;
+        return TRUE;
     }
     return FALSE;
 }

test/jdk/java/awt/Multiscreen/MultiScreenInsetsTest/MultiScreenInsetsTest.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2014, 2020, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2014, 2025, 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
@@ -24,12 +24,11 @@
 /*
   @test
   @key headful
-  @bug 8020443
-  @summary Frame is not created on the specified GraphicsDevice with two
-monitors
-  @author Oleg Pekhovskiy
+  @bug 8020443 6899304
+  @summary Test to check if the frame is created on the specified GraphicsDevice
+  and if getScreenInsets()returns the correct values across multiple monitors.
   @library /test/lib
-  @build jdk.test.lib.Platform
+  @build jdk.test.lib.Platform jtreg.SkippedException
   @run main MultiScreenInsetsTest
  */
 
@@ -42,47 +41,74 @@
 import java.awt.Toolkit;
 
 import jdk.test.lib.Platform;
+import jtreg.SkippedException;
 
 public class MultiScreenInsetsTest {
     private static final int SIZE = 100;
+    // Allow a margin tolerance of 1 pixel due to scaling
+    private static final int MARGIN_TOLERANCE = 1;
 
     public static void main(String[] args) throws InterruptedException {
-        if (!Platform.isLinux()) {
-            System.out.println("This test is for Linux only..." +
-                               "skipping!");
-            return;
-        }
-
         GraphicsEnvironment ge = GraphicsEnvironment.getLocalGraphicsEnvironment();
         GraphicsDevice[] gds = ge.getScreenDevices();
         if (gds.length < 2) {
-            System.out.println("It's a multi-screen test... skipping!");
-            return;
+            throw new SkippedException("It's a multi-screen test... skipping!");
         }
 
         for (int screen = 0; screen < gds.length; ++screen) {
             GraphicsDevice gd = gds[screen];
             GraphicsConfiguration gc = gd.getDefaultConfiguration();
             Rectangle bounds = gc.getBounds();
             Insets insets = Toolkit.getDefaultToolkit().getScreenInsets(gc);
+            System.out.println("Screen #" + screen);
+            System.out.println("Screen Bounds: " + bounds);
+            System.out.println("Insets: " + insets);
 
             Frame frame = new Frame(gc);
             frame.setLocation(bounds.x + (bounds.width - SIZE) / 2,
                               bounds.y + (bounds.height - SIZE) / 2);
             frame.setSize(SIZE, SIZE);
-            frame.setUndecorated(true);
+
+            /*
+             * On Windows, undecorated maximized frames are placed over the taskbar.
+             * Use a decorated frame instead.
+             */
+            if (Platform.isWindows()) {
+                frame.setUndecorated(false);
+            } else {
+                frame.setUndecorated(true);
+            }
+
             frame.setVisible(true);
 
             // Maximize Frame to reach the struts
             frame.setExtendedState(java.awt.Frame.MAXIMIZED_BOTH);
             Thread.sleep(2000);
 
             Rectangle frameBounds = frame.getBounds();
+            System.out.println("Frame bounds: " + frameBounds);
+
             frame.dispose();
+
+            /*
+             * On Windows, the top-left corner of an undecorated maximized frame
+             * may have negative coordinates (x, y).
+             * Adjust the frame bounds accordingly.
+             */
+            if (frameBounds.x < bounds.x) {
+                frameBounds.width -= (bounds.x - frameBounds.x) * 2;
+                frameBounds.x = bounds.x;
+            }
+            if (frameBounds.y < bounds.y) {
+                frameBounds.height -= (bounds.y - frameBounds.y) * 2;
+                frameBounds.y = bounds.y;
+            }
+            System.out.println("Adjusted Frame bounds: " + frameBounds);
+
             if (bounds.x + insets.left != frameBounds.x
                 || bounds.y + insets.top != frameBounds.y
-                || bounds.width - insets.right - insets.left != frameBounds.width
-                || bounds.height - insets.bottom - insets.top != frameBounds.height) {
+                || Math.abs((bounds.width - insets.right - insets.left) - frameBounds.width) > MARGIN_TOLERANCE
+                || Math.abs((bounds.height - insets.bottom - insets.top) - frameBounds.height) > MARGIN_TOLERANCE) {
                 throw new RuntimeException("Test FAILED! Wrong screen #" +
                                            screen + " insets: " + insets);
             }