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	/*
	* 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
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* 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.
	*/
	package javax.swing;

	import java.beans.PropertyChangeEvent;
	import java.beans.PropertyChangeListener;
	import java.beans.Transient;
	import java.util.*;

	import java.awt.*;
	import java.awt.event.*;

	import java.io.Serializable;
	import java.io.ObjectOutputStream;
	import java.io.IOException;

	import javax.swing.event.*;
	import javax.swing.plaf.*;

	import javax.accessibility.*;

	/**
	* A component that combines a button or editable field and a drop-down list.
	* The user can select a value from the drop-down list, which appears at the
	* user's request. If you make the combo box editable, then the combo box
	* includes an editable field into which the user can type a value.
	* <p>
	* <strong>Warning:</strong> Swing is not thread safe. For more
	* information see <a
	* href="package-summary.html#threading">Swing's Threading
	* Policy</a>.
	* <p>
	* <strong>Warning:</strong>
	* Serialized objects of this class will not be compatible with
	* future Swing releases. The current serialization support is
	* appropriate for short term storage or RMI between applications running
	* the same version of Swing. As of 1.4, support for long term storage
	* of all JavaBeans™
	* has been added to the <code>java.beans</code> package.
	* Please see {@link java.beans.XMLEncoder}.
	*
	* <p>
	* See <a href="https://docs.oracle.com/javase/tutorial/uiswing/components/combobox.html">How to Use Combo Boxes</a>
	* in <a href="https://docs.oracle.com/javase/tutorial/"><em>The Java Tutorial</em></a>
	* for further information.
	* <p>
	* @see ComboBoxModel
	* @see DefaultComboBoxModel
	*
	* @param <E> the type of the elements of this combo box
	*
	* @beaninfo
	* attribute: isContainer false
	* description: A combination of a text field and a drop-down list.
	*
	* @author Arnaud Weber
	* @author Mark Davidson
	*/
	public class JComboBox<E> extends JComponent
	implements ItemSelectable,ListDataListener,ActionListener, Accessible {
	/**
	* @see #getUIClassID
	* @see #readObject
	*/
	private static final String uiClassID = "ComboBoxUI";

	/**
	* This protected field is implementation specific. Do not access directly
	* or override. Use the accessor methods instead.
	*
	* @see #getModel
	* @see #setModel
	*/
	protected ComboBoxModel<E> dataModel;
	/**
	* This protected field is implementation specific. Do not access directly
	* or override. Use the accessor methods instead.
	*
	* @see #getRenderer
	* @see #setRenderer
	*/
	protected ListCellRenderer<? super E> renderer;
	/**
	* This protected field is implementation specific. Do not access directly
	* or override. Use the accessor methods instead.
	*
	* @see #getEditor
	* @see #setEditor
	*/
	protected ComboBoxEditor editor;
	/**
	* This protected field is implementation specific. Do not access directly
	* or override. Use the accessor methods instead.
	*
	* @see #getMaximumRowCount
	* @see #setMaximumRowCount
	*/
	protected int maximumRowCount = 8;

	/**
	* This protected field is implementation specific. Do not access directly
	* or override. Use the accessor methods instead.
	*
	* @see #isEditable
	* @see #setEditable
	*/
	protected boolean isEditable = false;
	/**
	* This protected field is implementation specific. Do not access directly
	* or override. Use the accessor methods instead.
	*
	* @see #setKeySelectionManager
	* @see #getKeySelectionManager
	*/
	protected KeySelectionManager keySelectionManager = null;
	/**
	* This protected field is implementation specific. Do not access directly
	* or override. Use the accessor methods instead.
	*
	* @see #setActionCommand
	* @see #getActionCommand
	*/
	protected String actionCommand = "comboBoxChanged";
	/**
	* This protected field is implementation specific. Do not access directly
	* or override. Use the accessor methods instead.
	*
	* @see #setLightWeightPopupEnabled
	* @see #isLightWeightPopupEnabled
	*/
	protected boolean lightWeightPopupEnabled = JPopupMenu.getDefaultLightWeightPopupEnabled();

	/**
	* This protected field is implementation specific. Do not access directly
	* or override.
	*/
	protected Object selectedItemReminder = null;

	private E prototypeDisplayValue;

	// Flag to ensure that infinite loops do not occur with ActionEvents.
	private boolean firingActionEvent = false;

	// Flag to ensure the we don't get multiple ActionEvents on item selection.
	private boolean selectingItem = false;

	/**
	* Creates a <code>JComboBox</code> that takes its items from an
	* existing <code>ComboBoxModel</code>. Since the
	* <code>ComboBoxModel</code> is provided, a combo box created using
	* this constructor does not create a default combo box model and
	* may impact how the insert, remove and add methods behave.
	*
	* @param aModel the <code>ComboBoxModel</code> that provides the
	* displayed list of items
	* @see DefaultComboBoxModel
	*/
	public JComboBox(ComboBoxModel<E> aModel) {
	super();
	setModel(aModel);
	init();
	}

	/**
	* Creates a <code>JComboBox</code> that contains the elements
	* in the specified array. By default the first item in the array
	* (and therefore the data model) becomes selected.
	*
	* @param items an array of objects to insert into the combo box
	* @see DefaultComboBoxModel
	*/
	public JComboBox(E[] items) {
	super();
	setModel(new DefaultComboBoxModel<E>(items));
	init();
	}

	/**
	* Creates a <code>JComboBox</code> that contains the elements
	* in the specified Vector. By default the first item in the vector
	* (and therefore the data model) becomes selected.
	*
	* @param items an array of vectors to insert into the combo box
	* @see DefaultComboBoxModel
	*/
	public JComboBox(Vector<E> items) {
	super();
	setModel(new DefaultComboBoxModel<E>(items));
	init();
	}

	/**
	* Creates a <code>JComboBox</code> with a default data model.
	* The default data model is an empty list of objects.
	* Use <code>addItem</code> to add items. By default the first item
	* in the data model becomes selected.
	*
	* @see DefaultComboBoxModel
	*/
	public JComboBox() {
	super();
	setModel(new DefaultComboBoxModel<E>());
	init();
	}

	private void init() {
	installAncestorListener();
	setUIProperty("opaque",true);
	updateUI();
	}

	protected void installAncestorListener() {
	addAncestorListener(new AncestorListener(){
	public void ancestorAdded(AncestorEvent event){ hidePopup();}
	public void ancestorRemoved(AncestorEvent event){ hidePopup();}
	public void ancestorMoved(AncestorEvent event){
	if (event.getSource() != JComboBox.this)
	hidePopup();
	}});
	}

	/**
	* Sets the L&F object that renders this component.
	*
	* @param ui the <code>ComboBoxUI</code> L&F object
	* @see UIDefaults#getUI
	*
	* @beaninfo
	* bound: true
	* hidden: true
	* attribute: visualUpdate true
	* description: The UI object that implements the Component's LookAndFeel.
	*/
	public void setUI(ComboBoxUI ui) {
	super.setUI(ui);
	}

	/**
	* Resets the UI property to a value from the current look and feel.
	*
	* @see JComponent#updateUI
	*/
	public void updateUI() {
	setUI((ComboBoxUI)UIManager.getUI(this));

	ListCellRenderer<? super E> renderer = getRenderer();
	if (renderer instanceof Component) {
	SwingUtilities.updateComponentTreeUI((Component)renderer);
	}
	}


	/**
	* Returns the name of the L&F class that renders this component.
	*
	* @return the string "ComboBoxUI"
	* @see JComponent#getUIClassID
	* @see UIDefaults#getUI
	*/
	public String getUIClassID() {
	return uiClassID;
	}


	/**
	* Returns the L&F object that renders this component.
	*
	* @return the ComboBoxUI object that renders this component
	*/
	public ComboBoxUI getUI() {
	return(ComboBoxUI)ui;
	}

	/**
	* Sets the data model that the <code>JComboBox</code> uses to obtain
	* the list of items.
	*
	* @param aModel the <code>ComboBoxModel</code> that provides the
	* displayed list of items
	*
	* @beaninfo
	* bound: true
	* description: Model that the combo box uses to get data to display.
	*/
	public void setModel(ComboBoxModel<E> aModel) {
	ComboBoxModel<E> oldModel = dataModel;
	if (oldModel != null) {
	oldModel.removeListDataListener(this);
	}
	dataModel = aModel;
	dataModel.addListDataListener(this);

	// set the current selected item.
	selectedItemReminder = dataModel.getSelectedItem();

	firePropertyChange( "model", oldModel, dataModel);
	}

	/**
	* Returns the data model currently used by the <code>JComboBox</code>.
	*
	* @return the <code>ComboBoxModel</code> that provides the displayed
	* list of items
	*/
	public ComboBoxModel<E> getModel() {
	return dataModel;
	}

	/*
	* Properties
	*/

	/**
	* Sets the <code>lightWeightPopupEnabled</code> property, which
	* provides a hint as to whether or not a lightweight
	* <code>Component</code> should be used to contain the
	* <code>JComboBox</code>, versus a heavyweight
	* <code>Component</code> such as a <code>Panel</code>
	* or a <code>Window</code>. The decision of lightweight
	* versus heavyweight is ultimately up to the
	* <code>JComboBox</code>. Lightweight windows are more
	* efficient than heavyweight windows, but lightweight
	* and heavyweight components do not mix well in a GUI.
	* If your application mixes lightweight and heavyweight
	* components, you should disable lightweight popups.
	* The default value for the <code>lightWeightPopupEnabled</code>
	* property is <code>true</code>, unless otherwise specified
	* by the look and feel. Some look and feels always use
	* heavyweight popups, no matter what the value of this property.
	* <p>
	* See the article <a href="http://www.oracle.com/technetwork/articles/java/mixing-components-433992.html">Mixing Heavy and Light Components</a>
	* This method fires a property changed event.
	*
	* @param aFlag if <code>true</code>, lightweight popups are desired
	*
	* @beaninfo
	* bound: true
	* expert: true
	* description: Set to <code>false</code> to require heavyweight popups.
	*/
	public void setLightWeightPopupEnabled(boolean aFlag) {
	boolean oldFlag = lightWeightPopupEnabled;
	lightWeightPopupEnabled = aFlag;
	firePropertyChange("lightWeightPopupEnabled", oldFlag, lightWeightPopupEnabled);
	}

	/**
	* Gets the value of the <code>lightWeightPopupEnabled</code>
	* property.
	*
	* @return the value of the <code>lightWeightPopupEnabled</code>
	* property
	* @see #setLightWeightPopupEnabled
	*/
	public boolean isLightWeightPopupEnabled() {
	return lightWeightPopupEnabled;
	}

	/**
	* Determines whether the <code>JComboBox</code> field is editable.
	* An editable <code>JComboBox</code> allows the user to type into the
	* field or selected an item from the list to initialize the field,
	* after which it can be edited. (The editing affects only the field,
	* the list item remains intact.) A non editable <code>JComboBox</code>
	* displays the selected item in the field,
	* but the selection cannot be modified.
	*
	* @param aFlag a boolean value, where true indicates that the
	* field is editable
	*
	* @beaninfo
	* bound: true
	* preferred: true
	* description: If true, the user can type a new value in the combo box.
	*/
	public void setEditable(boolean aFlag) {
	boolean oldFlag = isEditable;
	isEditable = aFlag;
	firePropertyChange( "editable", oldFlag, isEditable );
	}

	/**
	* Returns true if the <code>JComboBox</code> is editable.
	* By default, a combo box is not editable.
	*
	* @return true if the <code>JComboBox</code> is editable, else false
	*/
	public boolean isEditable() {
	return isEditable;
	}

	/**
	* Sets the maximum number of rows the <code>JComboBox</code> displays.
	* If the number of objects in the model is greater than count,
	* the combo box uses a scrollbar.
	*
	* @param count an integer specifying the maximum number of items to
	* display in the list before using a scrollbar
	* @beaninfo
	* bound: true
	* preferred: true
	* description: The maximum number of rows the popup should have
	*/
	public void setMaximumRowCount(int count) {
	int oldCount = maximumRowCount;
	maximumRowCount = count;
	firePropertyChange( "maximumRowCount", oldCount, maximumRowCount );
	}

	/**
	* Returns the maximum number of items the combo box can display
	* without a scrollbar
	*
	* @return an integer specifying the maximum number of items that are
	* displayed in the list before using a scrollbar
	*/
	public int getMaximumRowCount() {
	return maximumRowCount;
	}

	/**
	* Sets the renderer that paints the list items and the item selected from the list in
	* the JComboBox field. The renderer is used if the JComboBox is not
	* editable. If it is editable, the editor is used to render and edit
	* the selected item.
	* <p>
	* The default renderer displays a string or an icon.
	* Other renderers can handle graphic images and composite items.
	* <p>
	* To display the selected item,
	* <code>aRenderer.getListCellRendererComponent</code>
	* is called, passing the list object and an index of -1.
	*
	* @param aRenderer the <code>ListCellRenderer</code> that
	* displays the selected item
	* @see #setEditor
	* @beaninfo
	* bound: true
	* expert: true
	* description: The renderer that paints the item selected in the list.
	*/
	public void setRenderer(ListCellRenderer<? super E> aRenderer) {
	ListCellRenderer<? super E> oldRenderer = renderer;
	renderer = aRenderer;
	firePropertyChange( "renderer", oldRenderer, renderer );
	invalidate();
	}

	/**
	* Returns the renderer used to display the selected item in the
	* <code>JComboBox</code> field.
	*
	* @return the <code>ListCellRenderer</code> that displays
	* the selected item.
	*/
	public ListCellRenderer<? super E> getRenderer() {
	return renderer;
	}

	/**
	* Sets the editor used to paint and edit the selected item in the
	* <code>JComboBox</code> field. The editor is used only if the
	* receiving <code>JComboBox</code> is editable. If not editable,
	* the combo box uses the renderer to paint the selected item.
	*
	* @param anEditor the <code>ComboBoxEditor</code> that
	* displays the selected item
	* @see #setRenderer
	* @beaninfo
	* bound: true
	* expert: true
	* description: The editor that combo box uses to edit the current value
	*/
	public void setEditor(ComboBoxEditor anEditor) {
	ComboBoxEditor oldEditor = editor;

	if ( editor != null ) {
	editor.removeActionListener(this);
	}
	editor = anEditor;
	if ( editor != null ) {
	editor.addActionListener(this);
	}
	firePropertyChange( "editor", oldEditor, editor );
	}

	/**
	* Returns the editor used to paint and edit the selected item in the
	* <code>JComboBox</code> field.
	*
	* @return the <code>ComboBoxEditor</code> that displays the selected item
	*/
	public ComboBoxEditor getEditor() {
	return editor;
	}

	//
	// Selection
	//

	/**
	* Sets the selected item in the combo box display area to the object in
	* the argument.
	* If <code>anObject</code> is in the list, the display area shows
	* <code>anObject</code> selected.
	* <p>
	* If <code>anObject</code> is <i>not</i> in the list and the combo box is
	* uneditable, it will not change the current selection. For editable
	* combo boxes, the selection will change to <code>anObject</code>.
	* <p>
	* If this constitutes a change in the selected item,
	* <code>ItemListener</code>s added to the combo box will be notified with
	* one or two <code>ItemEvent</code>s.
	* If there is a current selected item, an <code>ItemEvent</code> will be
	* fired and the state change will be <code>ItemEvent.DESELECTED</code>.
	* If <code>anObject</code> is in the list and is not currently selected
	* then an <code>ItemEvent</code> will be fired and the state change will
	* be <code>ItemEvent.SELECTED</code>.
	* <p>
	* <code>ActionListener</code>s added to the combo box will be notified
	* with an <code>ActionEvent</code> when this method is called.
	*
	* @param anObject the list object to select; use <code>null</code> to
	clear the selection
	* @beaninfo
	* preferred: true
	* description: Sets the selected item in the JComboBox.
	*/
	public void setSelectedItem(Object anObject) {
	Object oldSelection = selectedItemReminder;
	Object objectToSelect = anObject;
	if (oldSelection == null \|\| !oldSelection.equals(anObject)) {

	if (anObject != null && !isEditable()) {
	// For non editable combo boxes, an invalid selection
	// will be rejected.
	boolean found = false;
	for (int i = 0; i < dataModel.getSize(); i++) {
	E element = dataModel.getElementAt(i);
	if (anObject.equals(element)) {
	found = true;
	objectToSelect = element;
	break;
	}
	}
	if (!found) {
	return;
	}
	}

	// Must toggle the state of this flag since this method
	// call may result in ListDataEvents being fired.
	selectingItem = true;
	dataModel.setSelectedItem(objectToSelect);
	selectingItem = false;

	if (selectedItemReminder != dataModel.getSelectedItem()) {
	// in case a users implementation of ComboBoxModel
	// doesn't fire a ListDataEvent when the selection
	// changes.
	selectedItemChanged();
	}
	}
	fireActionEvent();
	}

	/**
	* Returns the current selected item.
	* <p>
	* If the combo box is editable, then this value may not have been added
	* to the combo box with <code>addItem</code>, <code>insertItemAt</code>
	* or the data constructors.
	*
	* @return the current selected Object
	* @see #setSelectedItem
	*/
	public Object getSelectedItem() {
	return dataModel.getSelectedItem();
	}

	/**
	* Selects the item at index <code>anIndex</code>.
	*
	* @param anIndex an integer specifying the list item to select,
	* where 0 specifies the first item in the list and -1 indicates no selection
	* @exception IllegalArgumentException if <code>anIndex</code> < -1 or
	* <code>anIndex</code> is greater than or equal to size
	* @beaninfo
	* preferred: true
	* description: The item at index is selected.
	*/
	public void setSelectedIndex(int anIndex) {
	int size = dataModel.getSize();

	if ( anIndex == -1 ) {
	setSelectedItem( null );
	} else if ( anIndex < -1 \|\| anIndex >= size ) {
	throw new IllegalArgumentException("setSelectedIndex: " + anIndex + " out of bounds");
	} else {
	setSelectedItem(dataModel.getElementAt(anIndex));
	}
	}

	/**
	* Returns the first item in the list that matches the given item.
	* The result is not always defined if the <code>JComboBox</code>
	* allows selected items that are not in the list.
	* Returns -1 if there is no selected item or if the user specified
	* an item which is not in the list.

	* @return an integer specifying the currently selected list item,
	* where 0 specifies
	* the first item in the list;
	* or -1 if no item is selected or if
	* the currently selected item is not in the list
	*/
	@Transient
	public int getSelectedIndex() {
	Object sObject = dataModel.getSelectedItem();
	int i,c;
	E obj;

	for ( i=0,c=dataModel.getSize();i<c;i++ ) {
	obj = dataModel.getElementAt(i);
	if ( obj != null && obj.equals(sObject) )
	return i;
	}
	return -1;
	}

	/**
	* Returns the "prototypical display" value - an Object used
	* for the calculation of the display height and width.
	*
	* @return the value of the <code>prototypeDisplayValue</code> property
	* @see #setPrototypeDisplayValue
	* @since 1.4
	*/
	public E getPrototypeDisplayValue() {
	return prototypeDisplayValue;
	}

	/**
	* Sets the prototype display value used to calculate the size of the display
	* for the UI portion.
	* <p>
	* If a prototype display value is specified, the preferred size of
	* the combo box is calculated by configuring the renderer with the
	* prototype display value and obtaining its preferred size. Specifying
	* the preferred display value is often useful when the combo box will be
	* displaying large amounts of data. If no prototype display value has
	* been specified, the renderer must be configured for each value from
	* the model and its preferred size obtained, which can be
	* relatively expensive.
	*
	* @param prototypeDisplayValue
	* @see #getPrototypeDisplayValue
	* @since 1.4
	* @beaninfo
	* bound: true
	* attribute: visualUpdate true
	* description: The display prototype value, used to compute display width and height.
	*/
	public void setPrototypeDisplayValue(E prototypeDisplayValue) {
	Object oldValue = this.prototypeDisplayValue;
	this.prototypeDisplayValue = prototypeDisplayValue;
	firePropertyChange("prototypeDisplayValue", oldValue, prototypeDisplayValue);
	}

	/**
	* Adds an item to the item list.
	* This method works only if the <code>JComboBox</code> uses a
	* mutable data model.
	* <p>
	* <strong>Warning:</strong>
	* Focus and keyboard navigation problems may arise if you add duplicate
	* String objects. A workaround is to add new objects instead of String
	* objects and make sure that the toString() method is defined.
	* For example:
	* <pre>
	* comboBox.addItem(makeObj("Item 1"));
	* comboBox.addItem(makeObj("Item 1"));
	* ...
	* private Object makeObj(final String item) {
	* return new Object() { public String toString() { return item; } };
	* }
	* </pre>
	*
	* @param item the item to add to the list
	* @see MutableComboBoxModel
	*/
	public void addItem(E item) {
	checkMutableComboBoxModel();
	((MutableComboBoxModel<E>)dataModel).addElement(item);
	}

	/**
	* Inserts an item into the item list at a given index.
	* This method works only if the <code>JComboBox</code> uses a
	* mutable data model.
	*
	* @param item the item to add to the list
	* @param index an integer specifying the position at which
	* to add the item
	* @see MutableComboBoxModel
	*/
	public void insertItemAt(E item, int index) {
	checkMutableComboBoxModel();
	((MutableComboBoxModel<E>)dataModel).insertElementAt(item,index);
	}

	/**
	* Removes an item from the item list.
	* This method works only if the <code>JComboBox</code> uses a
	* mutable data model.
	*
	* @param anObject the object to remove from the item list
	* @see MutableComboBoxModel
	*/
	public void removeItem(Object anObject) {
	checkMutableComboBoxModel();
	((MutableComboBoxModel)dataModel).removeElement(anObject);
	}

	/**
	* Removes the item at <code>anIndex</code>
	* This method works only if the <code>JComboBox</code> uses a
	* mutable data model.
	*
	* @param anIndex an int specifying the index of the item to remove,
	* where 0
	* indicates the first item in the list
	* @see MutableComboBoxModel
	*/
	public void removeItemAt(int anIndex) {
	checkMutableComboBoxModel();
	((MutableComboBoxModel<E>)dataModel).removeElementAt( anIndex );
	}

	/**
	* Removes all items from the item list.
	*/
	public void removeAllItems() {
	checkMutableComboBoxModel();
	MutableComboBoxModel<E> model = (MutableComboBoxModel<E>)dataModel;
	int size = model.getSize();

	if ( model instanceof DefaultComboBoxModel ) {
	((DefaultComboBoxModel)model).removeAllElements();
	}
	else {
	for ( int i = 0; i < size; ++i ) {
	E element = model.getElementAt( 0 );
	model.removeElement( element );
	}
	}
	selectedItemReminder = null;
	if (isEditable()) {
	editor.setItem(null);
	}
	}

	/**
	* Checks that the <code>dataModel</code> is an instance of
	* <code>MutableComboBoxModel</code>. If not, it throws an exception.
	* @exception RuntimeException if <code>dataModel</code> is not an
	* instance of <code>MutableComboBoxModel</code>.
	*/
	void checkMutableComboBoxModel() {
	if ( !(dataModel instanceof MutableComboBoxModel) )
	throw new RuntimeException("Cannot use this method with a non-Mutable data model.");
	}

	/**
	* Causes the combo box to display its popup window.
	* @see #setPopupVisible
	*/
	public void showPopup() {
	setPopupVisible(true);
	}

	/**
	* Causes the combo box to close its popup window.
	* @see #setPopupVisible
	*/
	public void hidePopup() {
	setPopupVisible(false);
	}

	/**
	* Sets the visibility of the popup.
	*/
	public void setPopupVisible(boolean v) {
	getUI().setPopupVisible(this, v);
	}

	/**
	* Determines the visibility of the popup.
	*
	* @return true if the popup is visible, otherwise returns false
	*/
	public boolean isPopupVisible() {
	return getUI().isPopupVisible(this);
	}

	/ Selection /

	/**
	* Adds an <code>ItemListener</code>.
	* <p>
	* <code>aListener</code> will receive one or two <code>ItemEvent</code>s when
	* the selected item changes.
	*
	* @param aListener the <code>ItemListener</code> that is to be notified
	* @see #setSelectedItem
	*/
	public void addItemListener(ItemListener aListener) {
	listenerList.add(ItemListener.class,aListener);
	}

	/** Removes an <code>ItemListener</code>.
	*
	* @param aListener the <code>ItemListener</code> to remove
	*/
	public void removeItemListener(ItemListener aListener) {
	listenerList.remove(ItemListener.class,aListener);
	}

	/**
	* Returns an array of all the <code>ItemListener</code>s added
	* to this JComboBox with addItemListener().
	*
	* @return all of the <code>ItemListener</code>s added or an empty
	* array if no listeners have been added
	* @since 1.4
	*/
	public ItemListener[] getItemListeners() {
	return listenerList.getListeners(ItemListener.class);
	}

	/**
	* Adds an <code>ActionListener</code>.
	* <p>
	* The <code>ActionListener</code> will receive an <code>ActionEvent</code>
	* when a selection has been made. If the combo box is editable, then
	* an <code>ActionEvent</code> will be fired when editing has stopped.
	*
	* @param l the <code>ActionListener</code> that is to be notified
	* @see #setSelectedItem
	*/
	public void addActionListener(ActionListener l) {
	listenerList.add(ActionListener.class,l);
	}

	/** Removes an <code>ActionListener</code>.
	*
	* @param l the <code>ActionListener</code> to remove
	*/
	public void removeActionListener(ActionListener l) {
	if ((l != null) && (getAction() == l)) {
	setAction(null);
	} else {
	listenerList.remove(ActionListener.class, l);
	}
	}

	/**
	* Returns an array of all the <code>ActionListener</code>s added
	* to this JComboBox with addActionListener().
	*
	* @return all of the <code>ActionListener</code>s added or an empty
	* array if no listeners have been added
	* @since 1.4
	*/
	public ActionListener[] getActionListeners() {
	return listenerList.getListeners(ActionListener.class);
	}

	/**
	* Adds a <code>PopupMenu</code> listener which will listen to notification
	* messages from the popup portion of the combo box.
	* <p>
	* For all standard look and feels shipped with Java, the popup list
	* portion of combo box is implemented as a <code>JPopupMenu</code>.
	* A custom look and feel may not implement it this way and will
	* therefore not receive the notification.
	*
	* @param l the <code>PopupMenuListener</code> to add
	* @since 1.4
	*/
	public void addPopupMenuListener(PopupMenuListener l) {
	listenerList.add(PopupMenuListener.class,l);
	}

	/**
	* Removes a <code>PopupMenuListener</code>.
	*
	* @param l the <code>PopupMenuListener</code> to remove
	* @see #addPopupMenuListener
	* @since 1.4
	*/
	public void removePopupMenuListener(PopupMenuListener l) {
	listenerList.remove(PopupMenuListener.class,l);
	}

	/**
	* Returns an array of all the <code>PopupMenuListener</code>s added
	* to this JComboBox with addPopupMenuListener().
	*
	* @return all of the <code>PopupMenuListener</code>s added or an empty
	* array if no listeners have been added
	* @since 1.4
	*/
	public PopupMenuListener[] getPopupMenuListeners() {
	return listenerList.getListeners(PopupMenuListener.class);
	}

	/**
	* Notifies <code>PopupMenuListener</code>s that the popup portion of the
	* combo box will become visible.
	* <p>
	* This method is public but should not be called by anything other than
	* the UI delegate.
	* @see #addPopupMenuListener
	* @since 1.4
	*/
	public void firePopupMenuWillBecomeVisible() {
	Object[] listeners = listenerList.getListenerList();
	PopupMenuEvent e=null;
	for (int i = listeners.length-2; i>=0; i-=2) {
	if (listeners[i]==PopupMenuListener.class) {
	if (e == null)
	e = new PopupMenuEvent(this);
	((PopupMenuListener)listeners[i+1]).popupMenuWillBecomeVisible(e);
	}
	}
	}

	/**
	* Notifies <code>PopupMenuListener</code>s that the popup portion of the
	* combo box has become invisible.
	* <p>
	* This method is public but should not be called by anything other than
	* the UI delegate.
	* @see #addPopupMenuListener
	* @since 1.4
	*/
	public void firePopupMenuWillBecomeInvisible() {
	Object[] listeners = listenerList.getListenerList();
	PopupMenuEvent e=null;
	for (int i = listeners.length-2; i>=0; i-=2) {
	if (listeners[i]==PopupMenuListener.class) {
	if (e == null)
	e = new PopupMenuEvent(this);
	((PopupMenuListener)listeners[i+1]).popupMenuWillBecomeInvisible(e);
	}
	}
	}

	/**
	* Notifies <code>PopupMenuListener</code>s that the popup portion of the
	* combo box has been canceled.
	* <p>
	* This method is public but should not be called by anything other than
	* the UI delegate.
	* @see #addPopupMenuListener
	* @since 1.4
	*/
	public void firePopupMenuCanceled() {
	Object[] listeners = listenerList.getListenerList();
	PopupMenuEvent e=null;
	for (int i = listeners.length-2; i>=0; i-=2) {
	if (listeners[i]==PopupMenuListener.class) {
	if (e == null)
	e = new PopupMenuEvent(this);
	((PopupMenuListener)listeners[i+1]).popupMenuCanceled(e);
	}
	}
	}

	/**
	* Sets the action command that should be included in the event
	* sent to action listeners.
	*
	* @param aCommand a string containing the "command" that is sent
	* to action listeners; the same listener can then
	* do different things depending on the command it
	* receives
	*/
	public void setActionCommand(String aCommand) {
	actionCommand = aCommand;
	}

	/**
	* Returns the action command that is included in the event sent to
	* action listeners.
	*
	* @return the string containing the "command" that is sent
	* to action listeners.
	*/
	public String getActionCommand() {
	return actionCommand;
	}

	private Action action;
	private PropertyChangeListener actionPropertyChangeListener;

	/**
	* Sets the <code>Action</code> for the <code>ActionEvent</code> source.
	* The new <code>Action</code> replaces any previously set
	* <code>Action</code> but does not affect <code>ActionListeners</code>
	* independently added with <code>addActionListener</code>.
	* If the <code>Action</code> is already a registered
	* <code>ActionListener</code> for the <code>ActionEvent</code> source,
	* it is not re-registered.
	* <p>
	* Setting the <code>Action</code> results in immediately changing
	* all the properties described in <a href="Action.html#buttonActions">
	* Swing Components Supporting <code>Action</code></a>.
	* Subsequently, the combobox's properties are automatically updated
	* as the <code>Action</code>'s properties change.
	* <p>
	* This method uses three other methods to set
	* and help track the <code>Action</code>'s property values.
	* It uses the <code>configurePropertiesFromAction</code> method
	* to immediately change the combobox's properties.
	* To track changes in the <code>Action</code>'s property values,
	* this method registers the <code>PropertyChangeListener</code>
	* returned by <code>createActionPropertyChangeListener</code>. The
	* default {@code PropertyChangeListener} invokes the
	* {@code actionPropertyChanged} method when a property in the
	* {@code Action} changes.
	*
	* @param a the <code>Action</code> for the <code>JComboBox</code>,
	* or <code>null</code>.
	* @since 1.3
	* @see Action
	* @see #getAction
	* @see #configurePropertiesFromAction
	* @see #createActionPropertyChangeListener
	* @see #actionPropertyChanged
	* @beaninfo
	* bound: true
	* attribute: visualUpdate true
	* description: the Action instance connected with this ActionEvent source
	*/
	public void setAction(Action a) {
	Action oldValue = getAction();
	if (action==null \|\| !action.equals(a)) {
	action = a;
	if (oldValue!=null) {
	removeActionListener(oldValue);
	oldValue.removePropertyChangeListener(actionPropertyChangeListener);
	actionPropertyChangeListener = null;
	}
	configurePropertiesFromAction(action);
	if (action!=null) {
	// Don't add if it is already a listener
	if (!isListener(ActionListener.class, action)) {
	addActionListener(action);
	}
	// Reverse linkage:
	actionPropertyChangeListener = createActionPropertyChangeListener(action);
	action.addPropertyChangeListener(actionPropertyChangeListener);
	}
	firePropertyChange("action", oldValue, action);
	}
	}

	private boolean isListener(Class c, ActionListener a) {
	boolean isListener = false;
	Object[] listeners = listenerList.getListenerList();
	for (int i = listeners.length-2; i>=0; i-=2) {
	if (listeners[i]==c && listeners[i+1]==a) {
	isListener=true;
	}
	}
	return isListener;
	}

	/**
	* Returns the currently set <code>Action</code> for this
	* <code>ActionEvent</code> source, or <code>null</code> if no
	* <code>Action</code> is set.
	*
	* @return the <code>Action</code> for this <code>ActionEvent</code>
	* source; or <code>null</code>
	* @since 1.3
	* @see Action
	* @see #setAction
	*/
	public Action getAction() {
	return action;
	}

	/**
	* Sets the properties on this combobox to match those in the specified
	* <code>Action</code>. Refer to <a href="Action.html#buttonActions">
	* Swing Components Supporting <code>Action</code></a> for more
	* details as to which properties this sets.
	*
	* @param a the <code>Action</code> from which to get the properties,
	* or <code>null</code>
	* @since 1.3
	* @see Action
	* @see #setAction
	*/
	protected void configurePropertiesFromAction(Action a) {
	AbstractAction.setEnabledFromAction(this, a);
	AbstractAction.setToolTipTextFromAction(this, a);
	setActionCommandFromAction(a);
	}

	/**
	* Creates and returns a <code>PropertyChangeListener</code> that is
	* responsible for listening for changes from the specified
	* <code>Action</code> and updating the appropriate properties.
	* <p>
	* <b>Warning:</b> If you subclass this do not create an anonymous
	* inner class. If you do the lifetime of the combobox will be tied to
	* that of the <code>Action</code>.
	*
	* @param a the combobox's action
	* @since 1.3
	* @see Action
	* @see #setAction
	*/
	protected PropertyChangeListener createActionPropertyChangeListener(Action a) {
	return new ComboBoxActionPropertyChangeListener(this, a);
	}

	/**
	* Updates the combobox's state in response to property changes in
	* associated action. This method is invoked from the
	* {@code PropertyChangeListener} returned from
	* {@code createActionPropertyChangeListener}. Subclasses do not normally
	* need to invoke this. Subclasses that support additional {@code Action}
	* properties should override this and
	* {@code configurePropertiesFromAction}.
	* <p>
	* Refer to the table at <a href="Action.html#buttonActions">
	* Swing Components Supporting <code>Action</code></a> for a list of
	* the properties this method sets.
	*
	* @param action the <code>Action</code> associated with this combobox
	* @param propertyName the name of the property that changed
	* @since 1.6
	* @see Action
	* @see #configurePropertiesFromAction
	*/
	protected void actionPropertyChanged(Action action, String propertyName) {
	if (propertyName == Action.ACTION_COMMAND_KEY) {
	setActionCommandFromAction(action);
	} else if (propertyName == "enabled") {
	AbstractAction.setEnabledFromAction(this, action);
	} else if (Action.SHORT_DESCRIPTION == propertyName) {
	AbstractAction.setToolTipTextFromAction(this, action);
	}
	}

	private void setActionCommandFromAction(Action a) {
	setActionCommand((a != null) ?
	(String)a.getValue(Action.ACTION_COMMAND_KEY) :
	null);
	}


	private static class ComboBoxActionPropertyChangeListener
	extends ActionPropertyChangeListener<JComboBox<?>> {
	ComboBoxActionPropertyChangeListener(JComboBox<?> b, Action a) {
	super(b, a);
	}
	protected void actionPropertyChanged(JComboBox<?> cb,
	Action action,
	PropertyChangeEvent e) {
	if (AbstractAction.shouldReconfigure(e)) {
	cb.configurePropertiesFromAction(action);
	} else {
	cb.actionPropertyChanged(action, e.getPropertyName());
	}
	}
	}

	/**
	* Notifies all listeners that have registered interest for
	* notification on this event type.
	* @param e the event of interest
	*
	* @see EventListenerList
	*/
	protected void fireItemStateChanged(ItemEvent e) {
	// Guaranteed to return a non-null array
	Object[] listeners = listenerList.getListenerList();
	// Process the listeners last to first, notifying
	// those that are interested in this event
	for ( int i = listeners.length-2; i>=0; i-=2 ) {
	if ( listeners[i]==ItemListener.class ) {
	// Lazily create the event:
	// if (changeEvent == null)
	// changeEvent = new ChangeEvent(this);
	((ItemListener)listeners[i+1]).itemStateChanged(e);
	}
	}
	}

	/**
	* Notifies all listeners that have registered interest for
	* notification on this event type.
	*
	* @see EventListenerList
	*/
	protected void fireActionEvent() {
	if (!firingActionEvent) {
	// Set flag to ensure that an infinite loop is not created
	firingActionEvent = true;
	ActionEvent e = null;
	// Guaranteed to return a non-null array
	Object[] listeners = listenerList.getListenerList();
	long mostRecentEventTime = EventQueue.getMostRecentEventTime();
	int modifiers = 0;
	AWTEvent currentEvent = EventQueue.getCurrentEvent();
	if (currentEvent instanceof InputEvent) {
	modifiers = ((InputEvent)currentEvent).getModifiers();
	} else if (currentEvent instanceof ActionEvent) {
	modifiers = ((ActionEvent)currentEvent).getModifiers();
	}
	// Process the listeners last to first, notifying
	// those that are interested in this event
	for ( int i = listeners.length-2; i>=0; i-=2 ) {
	if ( listeners[i]==ActionListener.class ) {
	// Lazily create the event:
	if ( e == null )
	e = new ActionEvent(this,ActionEvent.ACTION_PERFORMED,
	getActionCommand(),
	mostRecentEventTime, modifiers);
	((ActionListener)listeners[i+1]).actionPerformed(e);
	}
	}
	firingActionEvent = false;
	}
	}

	/**
	* This protected method is implementation specific. Do not access directly
	* or override.
	*/
	protected void selectedItemChanged() {
	if (selectedItemReminder != null ) {
	fireItemStateChanged(new ItemEvent(this,ItemEvent.ITEM_STATE_CHANGED,
	selectedItemReminder,
	ItemEvent.DESELECTED));
	}

	// set the new selected item.
	selectedItemReminder = dataModel.getSelectedItem();

	if (selectedItemReminder != null ) {
	fireItemStateChanged(new ItemEvent(this,ItemEvent.ITEM_STATE_CHANGED,
	selectedItemReminder,
	ItemEvent.SELECTED));
	}
	}

	/**
	* Returns an array containing the selected item.
	* This method is implemented for compatibility with
	* <code>ItemSelectable</code>.
	*
	* @return an array of <code>Objects</code> containing one
	* element -- the selected item
	*/
	public Object[] getSelectedObjects() {
	Object selectedObject = getSelectedItem();
	if ( selectedObject == null )
	return new Object[0];
	else {
	Object result[] = new Object[1];
	result[0] = selectedObject;
	return result;
	}
	}

	/**
	* This method is public as an implementation side effect.
	* do not call or override.
	*/
	public void actionPerformed(ActionEvent e) {
	ComboBoxEditor editor = getEditor();
	if ((editor != null) && (e != null) && (editor == e.getSource()
	\|\| editor.getEditorComponent() == e.getSource())) {
	setPopupVisible(false);
	getModel().setSelectedItem(editor.getItem());
	String oldCommand = getActionCommand();
	setActionCommand("comboBoxEdited");
	fireActionEvent();
	setActionCommand(oldCommand);
	}
	}

	/**
	* This method is public as an implementation side effect.
	* do not call or override.
	*/
	public void contentsChanged(ListDataEvent e) {
	Object oldSelection = selectedItemReminder;
	Object newSelection = dataModel.getSelectedItem();
	if (oldSelection == null \|\| !oldSelection.equals(newSelection)) {
	selectedItemChanged();
	if (!selectingItem) {
	fireActionEvent();
	}
	}
	}

	/**
	* This method is public as an implementation side effect.
	* do not call or override.
	*/
	public void intervalAdded(ListDataEvent e) {
	if (selectedItemReminder != dataModel.getSelectedItem()) {
	selectedItemChanged();
	}
	}

	/**
	* This method is public as an implementation side effect.
	* do not call or override.
	*/
	public void intervalRemoved(ListDataEvent e) {
	contentsChanged(e);
	}

	/**
	* Selects the list item that corresponds to the specified keyboard
	* character and returns true, if there is an item corresponding
	* to that character. Otherwise, returns false.
	*
	* @param keyChar a char, typically this is a keyboard key
	* typed by the user
	*/
	public boolean selectWithKeyChar(char keyChar) {
	int index;

	if ( keySelectionManager == null )
	keySelectionManager = createDefaultKeySelectionManager();

	index = keySelectionManager.selectionForKey(keyChar,getModel());
	if ( index != -1 ) {
	setSelectedIndex(index);
	return true;
	}
	else
	return false;
	}

	/**
	* Enables the combo box so that items can be selected. When the
	* combo box is disabled, items cannot be selected and values
	* cannot be typed into its field (if it is editable).
	*
	* @param b a boolean value, where true enables the component and
	* false disables it
	* @beaninfo
	* bound: true
	* preferred: true
	* description: Whether the combo box is enabled.
	*/
	public void setEnabled(boolean b) {
	super.setEnabled(b);
	firePropertyChange( "enabled", !isEnabled(), isEnabled() );
	}

	/**
	* Initializes the editor with the specified item.
	*
	* @param anEditor the <code>ComboBoxEditor</code> that displays
	* the list item in the
	* combo box field and allows it to be edited
	* @param anItem the object to display and edit in the field
	*/
	public void configureEditor(ComboBoxEditor anEditor, Object anItem) {
	anEditor.setItem(anItem);
	}

	/**
	* Handles <code>KeyEvent</code>s, looking for the Tab key.
	* If the Tab key is found, the popup window is closed.
	*
	* @param e the <code>KeyEvent</code> containing the keyboard
	* key that was pressed
	*/
	public void processKeyEvent(KeyEvent e) {
	if ( e.getKeyCode() == KeyEvent.VK_TAB ) {
	hidePopup();
	}
	super.processKeyEvent(e);
	}

	/**
	* {@inheritDoc}
	*/
	@Override
	protected boolean processKeyBinding(KeyStroke ks, KeyEvent e, int condition, boolean pressed) {
	if (super.processKeyBinding(ks, e, condition, pressed)) {
	return true;
	}

	if (!isEditable() \|\| condition != WHEN_FOCUSED \|\| getEditor() == null
	\|\| !Boolean.TRUE.equals(getClientProperty("JComboBox.isTableCellEditor"))) {
	return false;
	}

	Component editorComponent = getEditor().getEditorComponent();
	if (editorComponent instanceof JComponent) {
	JComponent component = (JComponent) editorComponent;
	return component.processKeyBinding(ks, e, WHEN_FOCUSED, pressed);
	}
	return false;
	}

	/**
	* Sets the object that translates a keyboard character into a list
	* selection. Typically, the first selection with a matching first
	* character becomes the selected item.
	*
	* @beaninfo
	* expert: true
	* description: The objects that changes the selection when a key is pressed.
	*/
	public void setKeySelectionManager(KeySelectionManager aManager) {
	keySelectionManager = aManager;
	}

	/**
	* Returns the list's key-selection manager.
	*
	* @return the <code>KeySelectionManager</code> currently in use
	*/
	public KeySelectionManager getKeySelectionManager() {
	return keySelectionManager;
	}

	/* Accessing the model */
	/**
	* Returns the number of items in the list.
	*
	* @return an integer equal to the number of items in the list
	*/
	public int getItemCount() {
	return dataModel.getSize();
	}

	/**
	* Returns the list item at the specified index. If <code>index</code>
	* is out of range (less than zero or greater than or equal to size)
	* it will return <code>null</code>.
	*
	* @param index an integer indicating the list position, where the first
	* item starts at zero
	* @return the item at that list position; or
	* <code>null</code> if out of range
	*/
	public E getItemAt(int index) {
	return dataModel.getElementAt(index);
	}

	/**
	* Returns an instance of the default key-selection manager.
	*
	* @return the <code>KeySelectionManager</code> currently used by the list
	* @see #setKeySelectionManager
	*/
	protected KeySelectionManager createDefaultKeySelectionManager() {
	return new DefaultKeySelectionManager();
	}


	/**
	* The interface that defines a <code>KeySelectionManager</code>.
	* To qualify as a <code>KeySelectionManager</code>,
	* the class needs to implement the method
	* that identifies the list index given a character and the
	* combo box data model.
	*/
	public interface KeySelectionManager {
	/** Given <code>aKey</code> and the model, returns the row
	* that should become selected. Return -1 if no match was
	* found.
	*
	* @param aKey a char value, usually indicating a keyboard key that
	* was pressed
	* @param aModel a ComboBoxModel -- the component's data model, containing
	* the list of selectable items
	* @return an int equal to the selected row, where 0 is the
	* first item and -1 is none.
	*/
	int selectionForKey(char aKey,ComboBoxModel aModel);
	}

	class DefaultKeySelectionManager implements KeySelectionManager, Serializable {
	public int selectionForKey(char aKey,ComboBoxModel aModel) {
	int i,c;
	int currentSelection = -1;
	Object selectedItem = aModel.getSelectedItem();
	String v;
	String pattern;

	if ( selectedItem != null ) {
	for ( i=0,c=aModel.getSize();i<c;i++ ) {
	if ( selectedItem == aModel.getElementAt(i) ) {
	currentSelection = i;
	break;
	}
	}
	}

	pattern = ("" + aKey).toLowerCase();
	aKey = pattern.charAt(0);

	for ( i = ++currentSelection, c = aModel.getSize() ; i < c ; i++ ) {
	Object elem = aModel.getElementAt(i);
	if (elem != null && elem.toString() != null) {
	v = elem.toString().toLowerCase();
	if ( v.length() > 0 && v.charAt(0) == aKey )
	return i;
	}
	}

	for ( i = 0 ; i < currentSelection ; i ++ ) {
	Object elem = aModel.getElementAt(i);
	if (elem != null && elem.toString() != null) {
	v = elem.toString().toLowerCase();
	if ( v.length() > 0 && v.charAt(0) == aKey )
	return i;
	}
	}
	return -1;
	}
	}


	/**
	* See <code>readObject</code> and <code>writeObject</code> in
	* <code>JComponent</code> for more
	* information about serialization in Swing.
	*/
	private void writeObject(ObjectOutputStream s) throws IOException {
	s.defaultWriteObject();
	if (getUIClassID().equals(uiClassID)) {
	byte count = JComponent.getWriteObjCounter(this);
	JComponent.setWriteObjCounter(this, --count);
	if (count == 0 && ui != null) {
	ui.installUI(this);
	}
	}
	}


	/**
	* Returns a string representation of this <code>JComboBox</code>.
	* This method is intended to be used only for debugging purposes,
	* and the content and format of the returned string may vary between
	* implementations. The returned string may be empty but may not
	* be <code>null</code>.
	*
	* @return a string representation of this <code>JComboBox</code>
	*/
	protected String paramString() {
	String selectedItemReminderString = (selectedItemReminder != null ?
	selectedItemReminder.toString() :
	"");
	String isEditableString = (isEditable ? "true" : "false");
	String lightWeightPopupEnabledString = (lightWeightPopupEnabled ?
	"true" : "false");

	return super.paramString() +
	",isEditable=" + isEditableString +
	",lightWeightPopupEnabled=" + lightWeightPopupEnabledString +
	",maximumRowCount=" + maximumRowCount +
	",selectedItemReminder=" + selectedItemReminderString;
	}


	///////////////////
	// Accessibility support
	///////////////////

	/**
	* Gets the AccessibleContext associated with this JComboBox.
	* For combo boxes, the AccessibleContext takes the form of an
	* AccessibleJComboBox.
	* A new AccessibleJComboBox instance is created if necessary.
	*
	* @return an AccessibleJComboBox that serves as the
	* AccessibleContext of this JComboBox
	*/
	public AccessibleContext getAccessibleContext() {
	if ( accessibleContext == null ) {
	accessibleContext = new AccessibleJComboBox();
	}
	return accessibleContext;
	}

	/**
	* This class implements accessibility support for the
	* <code>JComboBox</code> class. It provides an implementation of the
	* Java Accessibility API appropriate to Combo Box user-interface elements.
	* <p>
	* <strong>Warning:</strong>
	* Serialized objects of this class will not be compatible with
	* future Swing releases. The current serialization support is
	* appropriate for short term storage or RMI between applications running
	* the same version of Swing. As of 1.4, support for long term storage
	* of all JavaBeans™
	* has been added to the <code>java.beans</code> package.
	* Please see {@link java.beans.XMLEncoder}.
	*/
	protected class AccessibleJComboBox extends AccessibleJComponent
	implements AccessibleAction, AccessibleSelection {


	private JList popupList; // combo box popup list
	private Accessible previousSelectedAccessible = null;

	/**
	* Returns an AccessibleJComboBox instance
	* @since 1.4
	*/
	public AccessibleJComboBox() {
	// set the combo box editor's accessible name and description
	JComboBox.this.addPropertyChangeListener(new AccessibleJComboBoxPropertyChangeListener());
	setEditorNameAndDescription();

	// Get the popup list
	Accessible a = getUI().getAccessibleChild(JComboBox.this, 0);
	if (a instanceof javax.swing.plaf.basic.ComboPopup) {
	// Listen for changes to the popup menu selection.
	popupList = ((javax.swing.plaf.basic.ComboPopup)a).getList();
	popupList.addListSelectionListener(
	new AccessibleJComboBoxListSelectionListener());
	}
	// Listen for popup menu show/hide events
	JComboBox.this.addPopupMenuListener(
	new AccessibleJComboBoxPopupMenuListener());
	}

	/*
	* JComboBox PropertyChangeListener
	*/
	private class AccessibleJComboBoxPropertyChangeListener
	implements PropertyChangeListener {

	public void propertyChange(PropertyChangeEvent e) {
	if (e.getPropertyName() == "editor") {
	// set the combo box editor's accessible name
	// and description
	setEditorNameAndDescription();
	}
	}
	}

	/*
	* Sets the combo box editor's accessible name and descripton
	*/
	private void setEditorNameAndDescription() {
	ComboBoxEditor editor = JComboBox.this.getEditor();
	if (editor != null) {
	Component comp = editor.getEditorComponent();
	if (comp instanceof Accessible) {
	AccessibleContext ac = comp.getAccessibleContext();
	if (ac != null) { // may be null
	ac.setAccessibleName(getAccessibleName());
	ac.setAccessibleDescription(getAccessibleDescription());
	}
	}
	}
	}

	/*
	* Listener for combo box popup menu
	* TIGER - 4669379 4894434
	*/
	private class AccessibleJComboBoxPopupMenuListener
	implements PopupMenuListener {

	/**
	* This method is called before the popup menu becomes visible
	*/
	public void popupMenuWillBecomeVisible(PopupMenuEvent e) {
	// save the initial selection
	if (popupList == null) {
	return;
	}
	int selectedIndex = popupList.getSelectedIndex();
	if (selectedIndex < 0) {
	return;
	}
	previousSelectedAccessible =
	popupList.getAccessibleContext().getAccessibleChild(selectedIndex);
	}

	/**
	* This method is called before the popup menu becomes invisible
	* Note that a JPopupMenu can become invisible any time
	*/
	public void popupMenuWillBecomeInvisible(PopupMenuEvent e) {
	// ignore
	}

	/**
	* This method is called when the popup menu is canceled
	*/
	public void popupMenuCanceled(PopupMenuEvent e) {
	// ignore
	}
	}

	/*
	* Handles changes to the popup list selection.
	* TIGER - 4669379 4894434 4933143
	*/
	private class AccessibleJComboBoxListSelectionListener
	implements ListSelectionListener {

	public void valueChanged(ListSelectionEvent e) {
	if (popupList == null) {
	return;
	}

	// Get the selected popup list item.
	int selectedIndex = popupList.getSelectedIndex();
	if (selectedIndex < 0) {
	return;
	}
	Accessible selectedAccessible =
	popupList.getAccessibleContext().getAccessibleChild(selectedIndex);
	if (selectedAccessible == null) {
	return;
	}

	// Fire a FOCUSED lost PropertyChangeEvent for the
	// previously selected list item.
	PropertyChangeEvent pce;

	if (previousSelectedAccessible != null) {
	pce = new PropertyChangeEvent(previousSelectedAccessible,
	AccessibleContext.ACCESSIBLE_STATE_PROPERTY,
	AccessibleState.FOCUSED, null);
	firePropertyChange(AccessibleContext.ACCESSIBLE_STATE_PROPERTY,
	null, pce);
	}
	// Fire a FOCUSED gained PropertyChangeEvent for the
	// currently selected list item.
	pce = new PropertyChangeEvent(selectedAccessible,
	AccessibleContext.ACCESSIBLE_STATE_PROPERTY,
	null, AccessibleState.FOCUSED);
	firePropertyChange(AccessibleContext.ACCESSIBLE_STATE_PROPERTY,
	null, pce);

	// Fire the ACCESSIBLE_ACTIVE_DESCENDANT_PROPERTY event
	// for the combo box.
	firePropertyChange(AccessibleContext.ACCESSIBLE_ACTIVE_DESCENDANT_PROPERTY,
	previousSelectedAccessible, selectedAccessible);

	// Save the previous selection.
	previousSelectedAccessible = selectedAccessible;
	}
	}


	/**
	* Returns the number of accessible children in the object. If all
	* of the children of this object implement Accessible, than this
	* method should return the number of children of this object.
	*
	* @return the number of accessible children in the object.
	*/
	public int getAccessibleChildrenCount() {
	// Always delegate to the UI if it exists
	if (ui != null) {
	return ui.getAccessibleChildrenCount(JComboBox.this);
	} else {
	return super.getAccessibleChildrenCount();
	}
	}

	/**
	* Returns the nth Accessible child of the object.
	* The child at index zero represents the popup.
	* If the combo box is editable, the child at index one
	* represents the editor.
	*
	* @param i zero-based index of child
	* @return the nth Accessible child of the object
	*/
	public Accessible getAccessibleChild(int i) {
	// Always delegate to the UI if it exists
	if (ui != null) {
	return ui.getAccessibleChild(JComboBox.this, i);
	} else {
	return super.getAccessibleChild(i);
	}
	}

	/**
	* Get the role of this object.
	*
	* @return an instance of AccessibleRole describing the role of the
	* object
	* @see AccessibleRole
	*/
	public AccessibleRole getAccessibleRole() {
	return AccessibleRole.COMBO_BOX;
	}

	/**
	* Gets the state set of this object. The AccessibleStateSet of
	* an object is composed of a set of unique AccessibleStates.
	* A change in the AccessibleStateSet of an object will cause a
	* PropertyChangeEvent to be fired for the ACCESSIBLE_STATE_PROPERTY
	* property.
	*
	* @return an instance of AccessibleStateSet containing the
	* current state set of the object
	* @see AccessibleStateSet
	* @see AccessibleState
	* @see #addPropertyChangeListener
	*
	*/
	public AccessibleStateSet getAccessibleStateSet() {
	// TIGER - 4489748
	AccessibleStateSet ass = super.getAccessibleStateSet();
	if (ass == null) {
	ass = new AccessibleStateSet();
	}
	if (JComboBox.this.isPopupVisible()) {
	ass.add(AccessibleState.EXPANDED);
	} else {
	ass.add(AccessibleState.COLLAPSED);
	}
	return ass;
	}

	/**
	* Get the AccessibleAction associated with this object. In the
	* implementation of the Java Accessibility API for this class,
	* return this object, which is responsible for implementing the
	* AccessibleAction interface on behalf of itself.
	*
	* @return this object
	*/
	public AccessibleAction getAccessibleAction() {
	return this;
	}

	/**
	* Return a description of the specified action of the object.
	*
	* @param i zero-based index of the actions
	*/
	public String getAccessibleActionDescription(int i) {
	if (i == 0) {
	return UIManager.getString("ComboBox.togglePopupText");
	}
	else {
	return null;
	}
	}

	/**
	* Returns the number of Actions available in this object. The
	* default behavior of a combo box is to have one action.
	*
	* @return 1, the number of Actions in this object
	*/
	public int getAccessibleActionCount() {
	return 1;
	}

	/**
	* Perform the specified Action on the object
	*
	* @param i zero-based index of actions
	* @return true if the the action was performed; else false.
	*/
	public boolean doAccessibleAction(int i) {
	if (i == 0) {
	setPopupVisible(!isPopupVisible());
	return true;
	}
	else {
	return false;
	}
	}


	/**
	* Get the AccessibleSelection associated with this object. In the
	* implementation of the Java Accessibility API for this class,
	* return this object, which is responsible for implementing the
	* AccessibleSelection interface on behalf of itself.
	*
	* @return this object
	*/
	public AccessibleSelection getAccessibleSelection() {
	return this;
	}

	/**
	* Returns the number of Accessible children currently selected.
	* If no children are selected, the return value will be 0.
	*
	* @return the number of items currently selected.
	* @since 1.3
	*/
	public int getAccessibleSelectionCount() {
	Object o = JComboBox.this.getSelectedItem();
	if (o != null) {
	return 1;
	} else {
	return 0;
	}
	}

	/**
	* Returns an Accessible representing the specified selected child
	* in the popup. If there isn't a selection, or there are
	* fewer children selected than the integer passed in, the return
	* value will be null.
	* <p>Note that the index represents the i-th selected child, which
	* is different from the i-th child.
	*
	* @param i the zero-based index of selected children
	* @return the i-th selected child
	* @see #getAccessibleSelectionCount
	* @since 1.3
	*/
	public Accessible getAccessibleSelection(int i) {
	// Get the popup
	Accessible a =
	JComboBox.this.getUI().getAccessibleChild(JComboBox.this, 0);
	if (a != null &&
	a instanceof javax.swing.plaf.basic.ComboPopup) {

	// get the popup list
	JList list = ((javax.swing.plaf.basic.ComboPopup)a).getList();

	// return the i-th selection in the popup list
	AccessibleContext ac = list.getAccessibleContext();
	if (ac != null) {
	AccessibleSelection as = ac.getAccessibleSelection();
	if (as != null) {
	return as.getAccessibleSelection(i);
	}
	}
	}
	return null;
	}

	/**
	* Determines if the current child of this object is selected.
	*
	* @return true if the current child of this object is selected;
	* else false
	* @param i the zero-based index of the child in this Accessible
	* object.
	* @see AccessibleContext#getAccessibleChild
	* @since 1.3
	*/
	public boolean isAccessibleChildSelected(int i) {
	return JComboBox.this.getSelectedIndex() == i;
	}

	/**
	* Adds the specified Accessible child of the object to the object's
	* selection. If the object supports multiple selections,
	* the specified child is added to any existing selection, otherwise
	* it replaces any existing selection in the object. If the
	* specified child is already selected, this method has no effect.
	*
	* @param i the zero-based index of the child
	* @see AccessibleContext#getAccessibleChild
	* @since 1.3
	*/
	public void addAccessibleSelection(int i) {
	// TIGER - 4856195
	clearAccessibleSelection();
	JComboBox.this.setSelectedIndex(i);
	}

	/**
	* Removes the specified child of the object from the object's
	* selection. If the specified item isn't currently selected, this
	* method has no effect.
	*
	* @param i the zero-based index of the child
	* @see AccessibleContext#getAccessibleChild
	* @since 1.3
	*/
	public void removeAccessibleSelection(int i) {
	if (JComboBox.this.getSelectedIndex() == i) {
	clearAccessibleSelection();
	}
	}

	/**
	* Clears the selection in the object, so that no children in the
	* object are selected.
	* @since 1.3
	*/
	public void clearAccessibleSelection() {
	JComboBox.this.setSelectedIndex(-1);
	}

	/**
	* Causes every child of the object to be selected
	* if the object supports multiple selections.
	* @since 1.3
	*/
	public void selectAllAccessibleSelection() {
	// do nothing since multiple selection is not supported
	}

	// public Accessible getAccessibleAt(Point p) {
	// Accessible a = getAccessibleChild(1);
	// if ( a != null ) {
	// return a; // the editor
	// }
	// else {
	// return getAccessibleChild(0); // the list
	// }
	// }
	private EditorAccessibleContext editorAccessibleContext = null;

	private class AccessibleEditor implements Accessible {
	public AccessibleContext getAccessibleContext() {
	if (editorAccessibleContext == null) {
	Component c = JComboBox.this.getEditor().getEditorComponent();
	if (c instanceof Accessible) {
	editorAccessibleContext =
	new EditorAccessibleContext((Accessible)c);
	}
	}
	return editorAccessibleContext;
	}
	}

	/*
	* Wrapper class for the AccessibleContext implemented by the
	* combo box editor. Delegates all method calls except
	* getAccessibleIndexInParent to the editor. The
	* getAccessibleIndexInParent method returns the selected
	* index in the combo box.
	*/
	private class EditorAccessibleContext extends AccessibleContext {

	private AccessibleContext ac;

	private EditorAccessibleContext() {
	}

	/*
	* @param a the AccessibleContext implemented by the
	* combo box editor
	*/
	EditorAccessibleContext(Accessible a) {
	this.ac = a.getAccessibleContext();
	}

	/**
	* Gets the accessibleName property of this object. The accessibleName
	* property of an object is a localized String that designates the purpose
	* of the object. For example, the accessibleName property of a label
	* or button might be the text of the label or button itself. In the
	* case of an object that doesn't display its name, the accessibleName
	* should still be set. For example, in the case of a text field used
	* to enter the name of a city, the accessibleName for the en_US locale
	* could be 'city.'
	*
	* @return the localized name of the object; null if this
	* object does not have a name
	*
	* @see #setAccessibleName
	*/
	public String getAccessibleName() {
	return ac.getAccessibleName();
	}

	/**
	* Sets the localized accessible name of this object. Changing the
	* name will cause a PropertyChangeEvent to be fired for the
	* ACCESSIBLE_NAME_PROPERTY property.
	*
	* @param s the new localized name of the object.
	*
	* @see #getAccessibleName
	* @see #addPropertyChangeListener
	*
	* @beaninfo
	* preferred: true
	* description: Sets the accessible name for the component.
	*/
	public void setAccessibleName(String s) {
	ac.setAccessibleName(s);
	}

	/**
	* Gets the accessibleDescription property of this object. The
	* accessibleDescription property of this object is a short localized
	* phrase describing the purpose of the object. For example, in the
	* case of a 'Cancel' button, the accessibleDescription could be
	* 'Ignore changes and close dialog box.'
	*
	* @return the localized description of the object; null if
	* this object does not have a description
	*
	* @see #setAccessibleDescription
	*/
	public String getAccessibleDescription() {
	return ac.getAccessibleDescription();
	}

	/**
	* Sets the accessible description of this object. Changing the
	* name will cause a PropertyChangeEvent to be fired for the
	* ACCESSIBLE_DESCRIPTION_PROPERTY property.
	*
	* @param s the new localized description of the object
	*
	* @see #setAccessibleName
	* @see #addPropertyChangeListener
	*
	* @beaninfo
	* preferred: true
	* description: Sets the accessible description for the component.
	*/
	public void setAccessibleDescription(String s) {
	ac.setAccessibleDescription(s);
	}

	/**
	* Gets the role of this object. The role of the object is the generic
	* purpose or use of the class of this object. For example, the role
	* of a push button is AccessibleRole.PUSH_BUTTON. The roles in
	* AccessibleRole are provided so component developers can pick from
	* a set of predefined roles. This enables assistive technologies to
	* provide a consistent interface to various tweaked subclasses of
	* components (e.g., use AccessibleRole.PUSH_BUTTON for all components
	* that act like a push button) as well as distinguish between subclasses
	* that behave differently (e.g., AccessibleRole.CHECK_BOX for check boxes
	* and AccessibleRole.RADIO_BUTTON for radio buttons).
	* <p>Note that the AccessibleRole class is also extensible, so
	* custom component developers can define their own AccessibleRole's
	* if the set of predefined roles is inadequate.
	*
	* @return an instance of AccessibleRole describing the role of the object
	* @see AccessibleRole
	*/
	public AccessibleRole getAccessibleRole() {
	return ac.getAccessibleRole();
	}

	/**
	* Gets the state set of this object. The AccessibleStateSet of an object
	* is composed of a set of unique AccessibleStates. A change in the
	* AccessibleStateSet of an object will cause a PropertyChangeEvent to
	* be fired for the ACCESSIBLE_STATE_PROPERTY property.
	*
	* @return an instance of AccessibleStateSet containing the
	* current state set of the object
	* @see AccessibleStateSet
	* @see AccessibleState
	* @see #addPropertyChangeListener
	*/
	public AccessibleStateSet getAccessibleStateSet() {
	return ac.getAccessibleStateSet();
	}

	/**
	* Gets the Accessible parent of this object.
	*
	* @return the Accessible parent of this object; null if this
	* object does not have an Accessible parent
	*/
	public Accessible getAccessibleParent() {
	return ac.getAccessibleParent();
	}

	/**
	* Sets the Accessible parent of this object. This is meant to be used
	* only in the situations where the actual component's parent should
	* not be treated as the component's accessible parent and is a method
	* that should only be called by the parent of the accessible child.
	*
	* @param a - Accessible to be set as the parent
	*/
	public void setAccessibleParent(Accessible a) {
	ac.setAccessibleParent(a);
	}

	/**
	* Gets the 0-based index of this object in its accessible parent.
	*
	* @return the 0-based index of this object in its parent; -1 if this
	* object does not have an accessible parent.
	*
	* @see #getAccessibleParent
	* @see #getAccessibleChildrenCount
	* @see #getAccessibleChild
	*/
	public int getAccessibleIndexInParent() {
	return JComboBox.this.getSelectedIndex();
	}

	/**
	* Returns the number of accessible children of the object.
	*
	* @return the number of accessible children of the object.
	*/
	public int getAccessibleChildrenCount() {
	return ac.getAccessibleChildrenCount();
	}

	/**
	* Returns the specified Accessible child of the object. The Accessible
	* children of an Accessible object are zero-based, so the first child
	* of an Accessible child is at index 0, the second child is at index 1,
	* and so on.
	*
	* @param i zero-based index of child
	* @return the Accessible child of the object
	* @see #getAccessibleChildrenCount
	*/
	public Accessible getAccessibleChild(int i) {
	return ac.getAccessibleChild(i);
	}

	/**
	* Gets the locale of the component. If the component does not have a
	* locale, then the locale of its parent is returned.
	*
	* @return this component's locale. If this component does not have
	* a locale, the locale of its parent is returned.
	*
	* @exception IllegalComponentStateException
	* If the Component does not have its own locale and has not yet been
	* added to a containment hierarchy such that the locale can be
	* determined from the containing parent.
	*/
	public Locale getLocale() throws IllegalComponentStateException {
	return ac.getLocale();
	}

	/**
	* Adds a PropertyChangeListener to the listener list.
	* The listener is registered for all Accessible properties and will
	* be called when those properties change.
	*
	* @see #ACCESSIBLE_NAME_PROPERTY
	* @see #ACCESSIBLE_DESCRIPTION_PROPERTY
	* @see #ACCESSIBLE_STATE_PROPERTY
	* @see #ACCESSIBLE_VALUE_PROPERTY
	* @see #ACCESSIBLE_SELECTION_PROPERTY
	* @see #ACCESSIBLE_TEXT_PROPERTY
	* @see #ACCESSIBLE_VISIBLE_DATA_PROPERTY
	*
	* @param listener The PropertyChangeListener to be added
	*/
	public void addPropertyChangeListener(PropertyChangeListener listener) {
	ac.addPropertyChangeListener(listener);
	}

	/**
	* Removes 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) {
	ac.removePropertyChangeListener(listener);
	}

	/**
	* Gets the AccessibleAction associated with this object that supports
	* one or more actions.
	*
	* @return AccessibleAction if supported by object; else return null
	* @see AccessibleAction
	*/
	public AccessibleAction getAccessibleAction() {
	return ac.getAccessibleAction();
	}

	/**
	* Gets the AccessibleComponent associated with this object that has a
	* graphical representation.
	*
	* @return AccessibleComponent if supported by object; else return null
	* @see AccessibleComponent
	*/
	public AccessibleComponent getAccessibleComponent() {
	return ac.getAccessibleComponent();
	}

	/**
	* Gets the AccessibleSelection associated with this object which allows its
	* Accessible children to be selected.
	*
	* @return AccessibleSelection if supported by object; else return null
	* @see AccessibleSelection
	*/
	public AccessibleSelection getAccessibleSelection() {
	return ac.getAccessibleSelection();
	}

	/**
	* Gets the AccessibleText associated with this object presenting
	* text on the display.
	*
	* @return AccessibleText if supported by object; else return null
	* @see AccessibleText
	*/
	public AccessibleText getAccessibleText() {
	return ac.getAccessibleText();
	}

	/**
	* Gets the AccessibleEditableText associated with this object
	* presenting editable text on the display.
	*
	* @return AccessibleEditableText if supported by object; else return null
	* @see AccessibleEditableText
	*/
	public AccessibleEditableText getAccessibleEditableText() {
	return ac.getAccessibleEditableText();
	}

	/**
	* Gets the AccessibleValue associated with this object that supports a
	* Numerical value.
	*
	* @return AccessibleValue if supported by object; else return null
	* @see AccessibleValue
	*/
	public AccessibleValue getAccessibleValue() {
	return ac.getAccessibleValue();
	}

	/**
	* Gets the AccessibleIcons associated with an object that has
	* one or more associated icons
	*
	* @return an array of AccessibleIcon if supported by object;
	* otherwise return null
	* @see AccessibleIcon
	*/
	public AccessibleIcon [] getAccessibleIcon() {
	return ac.getAccessibleIcon();
	}

	/**
	* Gets the AccessibleRelationSet associated with an object
	*
	* @return an AccessibleRelationSet if supported by object;
	* otherwise return null
	* @see AccessibleRelationSet
	*/
	public AccessibleRelationSet getAccessibleRelationSet() {
	return ac.getAccessibleRelationSet();
	}

	/**
	* Gets the AccessibleTable associated with an object
	*
	* @return an AccessibleTable if supported by object;
	* otherwise return null
	* @see AccessibleTable
	*/
	public AccessibleTable getAccessibleTable() {
	return ac.getAccessibleTable();
	}

	/**
	* Support for reporting bound property changes. If oldValue and
	* newValue are not equal and the PropertyChangeEvent listener list
	* is not empty, then fire a PropertyChange event to each listener.
	* In general, this is for use by the Accessible objects themselves
	* and should not be called by an application program.
	* @param propertyName The programmatic name of the property that
	* was changed.
	* @param oldValue The old value of the property.
	* @param newValue The new value of the property.
	* @see java.beans.PropertyChangeSupport
	* @see #addPropertyChangeListener
	* @see #removePropertyChangeListener
	* @see #ACCESSIBLE_NAME_PROPERTY
	* @see #ACCESSIBLE_DESCRIPTION_PROPERTY
	* @see #ACCESSIBLE_STATE_PROPERTY
	* @see #ACCESSIBLE_VALUE_PROPERTY
	* @see #ACCESSIBLE_SELECTION_PROPERTY
	* @see #ACCESSIBLE_TEXT_PROPERTY
	* @see #ACCESSIBLE_VISIBLE_DATA_PROPERTY
	*/
	public void firePropertyChange(String propertyName,
	Object oldValue,
	Object newValue) {
	ac.firePropertyChange(propertyName, oldValue, newValue);
	}
	}

	} // innerclass AccessibleJComboBox
	}

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