8332550: [macos] Voice Over: java.awt.IllegalComponentStateException: component must be showing on the screen to determine its location

Reviewed-by: asemenov, kizune, achung

Author: Abhishek Kumar

src/java.desktop/share/classes/javax/swing/table/JTableHeader.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1997, 2023, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2024, 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
@@ -1360,9 +1360,12 @@ public boolean contains(Point p) {
             }
 
             public Point getLocationOnScreen() {
-                if (parent != null) {
+                if (parent != null && parent.isShowing()) {
                     Point parentLocation = parent.getLocationOnScreen();
                     Point componentLocation = getLocation();
+                    if (parentLocation == null || componentLocation == null) {
+                        return null;
+                    }
                     componentLocation.translate(parentLocation.x, parentLocation.y);
                     return componentLocation;
                 } else {