7179482: Component.accessibleContext and JComponent.accessibleContext refactoring

Reviewed-by: art, anthony, alexsch

src/share/classes/java/awt/Component.java

 /*
- * Copyright (c) 1995, 2011, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1995, 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
@@ -8994,7 +8994,10 @@ public abstract class Component implements ImageObserver, MenuContainer,
      *  to the individual objects which extend Component.
      */
 
-    AccessibleContext accessibleContext = null;
+    /**
+     * The {@code AccessibleContext} associated with this {@code Component}.
+     */
+    protected AccessibleContext accessibleContext = null;
 
     /**
      * Gets the <code>AccessibleContext</code> associated
@@ -9034,6 +9037,13 @@ public abstract class Component implements ImageObserver, MenuContainer,
         protected AccessibleAWTComponent() {
         }
 
+        /**
+         * Number of PropertyChangeListener objects registered. It's used
+         * to add/remove ComponentListener and FocusListener to track
+         * target Component's state.
+         */
+        private volatile transient int propertyListenersCount = 0;
+
         protected ComponentListener accessibleAWTComponentHandler = null;
         protected FocusListener accessibleAWTFocusHandler = null;
 
@@ -9098,10 +9108,12 @@ public abstract class Component implements ImageObserver, MenuContainer,
         public void addPropertyChangeListener(PropertyChangeListener listener) {
             if (accessibleAWTComponentHandler == null) {
                 accessibleAWTComponentHandler = new AccessibleAWTComponentHandler();
-                Component.this.addComponentListener(accessibleAWTComponentHandler);
             }
             if (accessibleAWTFocusHandler == null) {
                 accessibleAWTFocusHandler = new AccessibleAWTFocusHandler();
+            }
+            if (propertyListenersCount++ == 0) {
+                Component.this.addComponentListener(accessibleAWTComponentHandler);
                 Component.this.addFocusListener(accessibleAWTFocusHandler);
             }
             super.addPropertyChangeListener(listener);
@@ -9115,13 +9127,9 @@ public abstract class Component implements ImageObserver, MenuContainer,
          * @param listener  The PropertyChangeListener to be removed
          */
         public void removePropertyChangeListener(PropertyChangeListener listener) {
-            if (accessibleAWTComponentHandler != null) {
+            if (--propertyListenersCount == 0) {
                 Component.this.removeComponentListener(accessibleAWTComponentHandler);
-                accessibleAWTComponentHandler = null;
-            }
-            if (accessibleAWTFocusHandler != null) {
                 Component.this.removeFocusListener(accessibleAWTFocusHandler);
-                accessibleAWTFocusHandler = null;
             }
             super.removePropertyChangeListener(listener);
         }

src/share/classes/java/awt/Container.java

 /*
- * Copyright (c) 1995, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1995, 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
@@ -3824,6 +3824,12 @@ public class Container extends Component {
             return Container.this.getAccessibleAt(p);
         }
 
+        /**
+         * Number of PropertyChangeListener objects registered. It's used
+         * to add/remove ContainerListener to track target Container's state.
+         */
+        private volatile transient int propertyListenersCount = 0;
+
         protected ContainerListener accessibleContainerHandler = null;
 
         /**
@@ -3859,11 +3865,27 @@ public class Container extends Component {
         public void addPropertyChangeListener(PropertyChangeListener listener) {
             if (accessibleContainerHandler == null) {
                 accessibleContainerHandler = new AccessibleContainerHandler();
+            }
+            if (propertyListenersCount++ == 0) {
                 Container.this.addContainerListener(accessibleContainerHandler);
             }
             super.addPropertyChangeListener(listener);
         }
 
+        /**
+         * Remove a PropertyChangeListener from the listener list.
+         * This removes a PropertyChangeListener that was registered
+         * for all properties.
+         *
+         * @param listener the PropertyChangeListener to be removed
+         */
+        public void removePropertyChangeListener(PropertyChangeListener listener) {
+            if (--propertyListenersCount == 0) {
+                Container.this.removeContainerListener(accessibleContainerHandler);
+            }
+            super.removePropertyChangeListener(listener);
+        }
+
     } // inner class AccessibleAWTContainer
 
     /**

src/share/classes/javax/swing/JComponent.java

 /*
- * Copyright (c) 1997, 2012, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 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
@@ -3643,26 +3643,6 @@ public abstract class JComponent extends Container implements Serializable,
         }
     }
 
-    /**
-     * The <code>AccessibleContext</code> associated with this
-     * <code>JComponent</code>.
-     */
-    protected AccessibleContext accessibleContext = null;
-
-    /**
-     * Returns the <code>AccessibleContext</code> associated with this
-     * <code>JComponent</code>.  The method implemented by this base
-     * class returns null.  Classes that extend <code>JComponent</code>
-     * should implement this method to return the
-     * <code>AccessibleContext</code> associated with the subclass.
-     *
-     * @return the <code>AccessibleContext</code> of this
-     *          <code>JComponent</code>
-     */
-    public AccessibleContext getAccessibleContext() {
-        return accessibleContext;
-    }
-
     /**
      * Inner class of JComponent used to provide default support for
      * accessibility.  This class is not meant to be used directly by
@@ -3689,7 +3669,18 @@ public abstract class JComponent extends Container implements Serializable,
             super();
         }
 
-        protected ContainerListener accessibleContainerHandler = null;
+        /**
+         * Number of PropertyChangeListener objects registered. It's used
+         * to add/remove ContainerListener and FocusListener to track
+         * target JComponent's state
+         */
+        private volatile transient int propertyListenersCount = 0;
+
+        /**
+         * This field duplicates the one in java.awt.Component.AccessibleAWTComponent,
+         * so it has been deprecated.
+         */
+        @Deprecated
         protected FocusListener accessibleFocusHandler = null;
 
         /**
@@ -3747,10 +3738,12 @@ public abstract class JComponent extends Container implements Serializable,
         public void addPropertyChangeListener(PropertyChangeListener listener) {
             if (accessibleFocusHandler == null) {
                 accessibleFocusHandler = new AccessibleFocusHandler();
-                JComponent.this.addFocusListener(accessibleFocusHandler);
             }
             if (accessibleContainerHandler == null) {
                 accessibleContainerHandler = new AccessibleContainerHandler();
+            }
+            if (propertyListenersCount++ == 0) {
+                JComponent.this.addFocusListener(accessibleFocusHandler);
                 JComponent.this.addContainerListener(accessibleContainerHandler);
             }
             super.addPropertyChangeListener(listener);
@@ -3764,9 +3757,9 @@ public abstract class JComponent extends Container implements Serializable,
          * @param listener  the PropertyChangeListener to be removed
          */
         public void removePropertyChangeListener(PropertyChangeListener listener) {
-            if (accessibleFocusHandler != null) {
+            if (--propertyListenersCount == 0) {
                 JComponent.this.removeFocusListener(accessibleFocusHandler);
-                accessibleFocusHandler = null;
+                JComponent.this.removeContainerListener(accessibleContainerHandler);
             }
             super.removePropertyChangeListener(listener);
         }