src/java.desktop/share/classes/java/awt/ContainerOrderFocusTraversalPolicy.java

*** 1,7 ****
  /*
!  * Copyright (c) 2000, 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
--- 1,7 ----
  /*
!  * Copyright (c) 2000, 2019, 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
*** 26,35 ****
--- 26,43 ----
  
  import java.util.List;
  import java.util.ArrayList;
  import sun.util.logging.PlatformLogger;
  
+ import java.util.Enumeration;
+ import sun.awt.SunToolkit;
+ import javax.swing.AbstractButton;
+ import javax.swing.ButtonGroup;
+ import javax.swing.ButtonModel;
+ import javax.swing.JToggleButton;
+ 
+ 
  /**
   * A FocusTraversalPolicy that determines traversal order based on the order
   * of child Components in a Container. From a particular focus cycle root, the
   * policy makes a pre-order traversal of the Component hierarchy, and traverses
   * a Container's children according to the ordering of the array returned by
*** 583,592 ****
--- 591,624 ----
      protected boolean accept(Component aComponent) {
          if (!aComponent.canBeFocusOwner()) {
              return false;
          }
  
+         if (SunToolkit.isInstanceOf(aComponent,
+                 "javax.swing.JToggleButton")) {
+             ButtonModel model = ((JToggleButton)aComponent).getModel();
+             if (model != null) {
+                 ButtonGroup group = model.getGroup();
+                 if (group != null) {
+                     Enumeration<AbstractButton> elements =
+                             group.getElements();
+                     int idx = 0;
+                     while (group.getElements().hasMoreElements()) {
+                         AbstractButton member = elements.nextElement();
+                         if (member instanceof JToggleButton &&
+                                 member.isVisible() && member.isDisplayable() &&
+                                 member.isEnabled() && member.isFocusable()) {
+                             if (member == aComponent) {
+                                 return idx == 0;
+                             }
+                             idx++;
+                         }
+                     }
+                 }
+             }
+         }
+ 
          // Verify that the Component is recursively enabled. Disabling a
          // heavyweight Container disables its children, whereas disabling
          // a lightweight Container does not.
          if (!(aComponent instanceof Window)) {
              for (Container enableTest = aComponent.getParent();