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	/*
	* Copyright (c) 2002, 2015, 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 com.sun.java.accessibility.util;

	import java.lang.*;
	import java.beans.*;
	import java.util.*;
	import java.awt.*;
	import java.awt.event.*;
	import java.awt.image.*;
	// Do not import Swing classes. This module is intended to work
	// with both Swing and AWT.
	// import javax.swing.*;
	import javax.accessibility.*;

	/**
	* <p>The {@code Translator} class provides a translation to interface
	* {@link javax.accessibility.Accessible Accessible}
	* for objects that do not implement interface {@code Accessible}. Assistive
	* technologies can use the {@link #getAccessible getAccessible} class method of
	* {@code Translator} to obtain an object that implements interface {@code Accessible}.
	* If the object passed in already implements interface {@code Accessible},
	* {@code getAccessible} merely returns the object.
	*
	* <p>An example of how an assistive technology might use the {@code Translator}
	* class is as follows:
	*
	* <PRE>
	* Accessible accessible = Translator.getAccessible(someObj);
	* // obtain information from the 'accessible' object.
	* </PRE>
	*
	* <P>Note: This implementation is missing many things and is not a recommended way
	* to implement accessibility features for a toolkit. Instead of relying upon this
	* code, a toolkit's components should implement interface {@code Accessible} directly.
	*/
	@jdk.Exported
	public class Translator extends AccessibleContext
	implements Accessible, AccessibleComponent {

	/** The source object needing translating. */
	protected Object source;

	/**
	* Find a translator for this class. If one doesn't exist for this
	* class explicitly, try its superclass and so on.
	*
	* @param c a Class
	* @return the {@code Translator} Class for the Class passed in
	*/
	protected static Class getTranslatorClass(Class c) {
	Class t = null;
	if (c == null) {
	return null;
	}
	try {
	t = Class.forName("com.sun.java.accessibility.util."
	+ c.getName()
	+ "Translator");
	return t;
	} catch (Exception e) {
	return getTranslatorClass(c.getSuperclass());
	}
	}

	/**
	* Obtain an object that implements interface {@code Accessible}. If the object
	* passed in already implements interface {@code Accessible}, {@code getAccessible}
	* merely returns the object.
	*
	* @param o an Object; if a null is passed in a null is returned
	* @return an {@code Object}, possibly the {@code Object} passed in, that
	* implements the {@code Accessible} interface for the {@code Object}
	* which was passed in
	*/
	public static Accessible getAccessible(Object o) {
	Accessible a = null;

	if (o == null) {
	return null;
	}
	if (o instanceof Accessible) {
	a = (Accessible)o;
	} else {
	Class translatorClass = getTranslatorClass(o.getClass());
	if (translatorClass != null) {
	try {
	Translator t = (Translator)translatorClass.newInstance();
	t.setSource(o);
	a = t;
	} catch (Exception e) {
	}
	}
	}
	if (a == null) {
	a = new Translator(o);
	}
	return a;
	}

	/**
	* Create a new {@code Translator}. You must call the {@link #setSource setSource}
	* method to set the object to be translated after calling this constructor.
	*/
	public Translator() {
	}

	/**
	* Create a new {@code Translator} with the source object o.
	*
	* @param o the Component that does not implement interface
	* {@link javax.accessibility.Accessible Accessible}
	*/
	public Translator(Object o) {
	source = o;
	}

	/**
	* Get the source {@code Object} of the {@code Translator}.
	*
	* @return the source {@code Object} of the {@code Translator}
	*/
	public Object getSource() {
	return source;
	}

	/**
	* Set the source object of the {@code Translator}.
	*
	* @param o the Component that does not implement interface Accessible
	*/
	public void setSource(Object o) {
	source = o;
	}

	/**
	* Returns true if this object is the same as the one passed in.
	*
	* @param o the {@code Object} to check against
	* @return true if this is the same object
	*/
	public boolean equals(Object o) {
	return source.equals(o);
	}


	// Accessible methods

	/**
	* Returns this object.
	*/
	public AccessibleContext getAccessibleContext() {
	return this;
	}

	// AccessibleContext methods

	/**
	* Get the accessible name of this object.
	*
	* @return the localized name of the object; can be null if this object
	* does not have a name
	*/
	public String getAccessibleName() {
	if (source instanceof MenuItem) {
	return ((MenuItem) source).getLabel();
	} else if (source instanceof Component) {
	return ((Component) source).getName();
	} else {
	return null;
	}
	}

	/**
	* Set the name of this object.
	*/
	public void setAccessibleName(String s) {
	if (source instanceof MenuItem) {
	((MenuItem) source).setLabel(s);
	} else if (source instanceof Component) {
	((Component) source).setName(s);
	}
	}

	/**
	* Get the accessible description of this object.
	*
	* @return the description of the object; can be null if this object does
	* not have a description
	*/
	public String getAccessibleDescription() {
	return null;
	}

	/**
	* Set the accessible description of this object.
	*
	* @param s the new localized description of the object
	*/
	public void setAccessibleDescription(String s) {
	}

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


	/**
	* Get the state of this object, given an already populated state.
	* This method is intended for use by subclasses so they don't have
	* to check for everything.
	*
	* @return an instance of {@code AccessibleStateSet}
	* containing the current state of the object
	*/
	public AccessibleStateSet getAccessibleStateSet() {
	AccessibleStateSet states = new AccessibleStateSet();
	if (source instanceof Component) {
	Component c = (Component) source;
	for (Container p = c.getParent(); p != null; p = p.getParent()) {
	if (p instanceof Window) {
	if (((Window)p).getFocusOwner() == c) {
	states.add(AccessibleState.FOCUSED);
	}
	}
	}
	}
	if (isEnabled()) {
	states.add(AccessibleState.ENABLED);
	}
	if (isFocusTraversable()) {
	states.add(AccessibleState.FOCUSABLE);
	}
	if (source instanceof MenuItem) {
	states.add(AccessibleState.FOCUSABLE);
	}
	return states;
	}

	/**
	* Get the accessible parent of this object.
	*
	* @return the accessible parent of this object; can be null if this
	* object does not have an accessible parent
	*/
	public Accessible getAccessibleParent() {
	if (accessibleParent != null) {
	return accessibleParent;
	} else if (source instanceof Component) {
	return getAccessible(((Component) source).getParent());
	} else {
	return null;
	}
	}

	/**
	* Get the index of this object in its accessible parent.
	*
	* @return -1 of this object does not have an accessible parent; otherwise,
	* the index of the child in its accessible parent
	*/
	public int getAccessibleIndexInParent() {
	if (source instanceof Component) {
	Container parent = ((Component) source).getParent();
	if (parent != null) {
	Component ca[] = parent.getComponents();
	for (int i = 0; i < ca.length; i++) {
	if (source.equals(ca[i])) {
	return i;
	}
	}
	}
	}
	return -1;
	}

	/**
	* Returns the number of accessible children in the object.
	*
	* @return the number of accessible children in the object
	*/
	public int getAccessibleChildrenCount() {
	if (source instanceof Container) {
	Component[] children = ((Container) source).getComponents();
	int count = 0;
	for (int i = 0; i < children.length; i++) {
	Accessible a = getAccessible(children[i]);
	if (a != null) {
	count++;
	}
	}
	return count;
	} else {
	return 0;
	}
	}

	/**
	* Return the nth accessible child of the object.
	*
	* @param i zero-based index of child
	* @return the nth accessible child of the object
	*/
	public Accessible getAccessibleChild(int i) {
	if (source instanceof Container) {
	Component[] children = ((Container) source).getComponents();
	int count = 0;

	for (int j = 0; j < children.length; j++) {
	Accessible a = getAccessible(children[j]);
	if (a != null) {
	if (count == i) {
	AccessibleContext ac = a.getAccessibleContext();
	if (ac != null) {
	ac.setAccessibleParent(this);
	}
	return a;
	} else {
	count++;
	}
	}
	}
	}
	return null;
	}

	/**
	* Gets the {@code Locale} of the component. If the component does not have a
	* locale, the locale of its parent is returned.
	*
	* @return the {@code Locale} of the object
	*/
	public Locale getLocale() throws IllegalComponentStateException {
	if (source instanceof Component) {
	return ((Component) source).getLocale();
	} else {
	return null;
	}
	}

	/**
	* Add a {@code PropertyChangeListener} to the listener list. The listener
	* is registered for all properties.
	*/
	public void addPropertyChangeListener(PropertyChangeListener l) {
	}

	/**
	* Remove the {@code PropertyChangeListener} from the listener list.
	*/
	public void removePropertyChangeListener(PropertyChangeListener l) {
	}

	// AccessibleComponent methods

	/**
	* Get the background {@code Color} of this object.
	*
	* @return if supported, the background {@code Color} of the object;
	* otherwise, null
	*
	*/
	public Color getBackground() {
	if (source instanceof Component) { // MenuComponent doesn't do background
	return ((Component) source).getBackground();
	} else {
	return null;
	}
	}

	/**
	* Set the background {@code Color} of this object.
	*
	* @param c the new {@code Color} for the background
	*/
	public void setBackground(Color c) {
	if (source instanceof Component) { // MenuComponent doesn't do background
	((Component) source).setBackground(c);
	}
	}

	/**
	* Get the foreground {@code Color} of this object.
	*
	* @return if supported, the foreground {@code Color} of the object; otherwise, null
	*/
	public Color getForeground() {
	if (source instanceof Component) { // MenuComponent doesn't do foreground
	return ((Component) source).getForeground();
	} else {
	return null;
	}
	}

	/**
	* Set the foreground {@code Color} of this object.
	*
	* @param c the new {@code Color} for the foreground
	*/
	public void setForeground(Color c) {
	if (source instanceof Component) { // MenuComponent doesn't do foreground
	((Component) source).setForeground(c);
	}
	}

	/**
	* Get the {@code Cursor} of this object.
	*
	* @return if supported, the Cursor of the object; otherwise, null
	*/
	public Cursor getCursor() {
	if (source instanceof Component) { // MenuComponent doesn't do cursor
	return ((Component) source).getCursor();
	} else {
	return null;
	}
	}

	/**
	* Set the {@code Cursor} of this object.
	* @param c the new {@code Cursor} for the object
	*/
	public void setCursor(Cursor c) {
	if (source instanceof Component) { // MenuComponent doesn't do cursor
	((Component) source).setCursor(c);
	}
	}

	/**
	* Get the {@code Font} of this object.
	*
	* @return if supported, the {@code Font} for the object; otherwise, null
	*/
	public Font getFont() {
	if (source instanceof Component) {
	return ((Component) source).getFont();
	} else if (source instanceof MenuComponent) {
	return ((MenuComponent) source).getFont();
	} else {
	return null;
	}
	}

	/**
	* Set the {@code Font} of this object.
	*
	* @param f the new {@code Font} for the object
	*/
	public void setFont(Font f) {
	if (source instanceof Component) {
	((Component) source).setFont(f);
	} else if (source instanceof MenuComponent) {
	((MenuComponent) source).setFont(f);
	}
	}

	/**
	* Get the {@code FontMetrics} of this object.
	*
	* @param f the {@code Font}
	* @return if supported, the {@code FontMetrics} the object; otherwise, null
	* @see #getFont
	*/
	public FontMetrics getFontMetrics(Font f) {
	if (source instanceof Component) {
	return ((Component) source).getFontMetrics(f);
	} else {
	return null;
	}
	}

	/**
	* Determine if the object is enabled.
	*
	* @return true if object is enabled; otherwise, false
	*/
	public boolean isEnabled() {
	if (source instanceof Component) {
	return ((Component) source).isEnabled();
	} else if (source instanceof MenuItem) {
	return ((MenuItem) source).isEnabled();
	} else {
	return true;
	}
	}

	/**
	* Set the enabled state of the object.
	*
	* @param b if true, enables this object; otherwise, disables it
	*/
	public void setEnabled(boolean b) {
	if (source instanceof Component) {
	((Component) source).setEnabled(b);
	} else if (source instanceof MenuItem) {
	((MenuItem) source).setEnabled(b);
	}
	}

	/**
	* Determine if the object is visible.
	*
	* @return true if object is visible; otherwise, false
	*/
	public boolean isVisible() {
	if (source instanceof Component) {
	return ((Component) source).isVisible();
	} else {
	return false;
	}
	}

	/**
	* Set the visible state of the object.
	*
	* @param b if true, shows this object; otherwise, hides it
	*/
	public void setVisible(boolean b) {
	if (source instanceof Component) {
	((Component) source).setVisible(b);
	}
	}

	/**
	* Determine if the object is showing. This is determined by checking
	* the visibility of the object and ancestors of the object.
	*
	* @return true if object is showing; otherwise, false
	*/
	public boolean isShowing() {
	if (source instanceof Component) {
	return ((Component) source).isShowing();
	} else {
	return false;
	}
	}

	/**
	* Checks whether the specified {@code Point} is within this
	* object's bounds, where the {@code Point} is relative to the coordinate
	* system of the object.
	*
	* @param p the {@code Point} relative to the coordinate system of the object
	* @return true if object contains {@code Point}; otherwise false
	*/
	public boolean contains(Point p) {
	if (source instanceof Component) {
	return ((Component) source).contains(p);
	} else {
	return false;
	}
	}

	/**
	* Returns the location of the object on the screen.
	*
	* @return location of object on screen; can be null if this object
	* is not on the screen
	*/
	public Point getLocationOnScreen() {
	if (source instanceof Component) {
	return ((Component) source).getLocationOnScreen();
	} else {
	return null;
	}
	}

	/**
	* Returns the location of the object relative to parent.
	*
	* @return location of object relative to parent; can be null if
	* this object or its parent are not on the screen
	*/
	public Point getLocation() {
	if (source instanceof Component) {
	return ((Component) source).getLocation();
	} else {
	return null;
	}
	}

	/**
	* Sets the location of the object relative to parent.
	*/
	public void setLocation(Point p) {
	if (source instanceof Component) {
	((Component) source).setLocation(p);
	}
	}

	/**
	* Returns the current bounds of this object.
	*
	* @return current bounds of object; can be null if this object
	* is not on the screen
	*/
	public Rectangle getBounds() {
	if (source instanceof Component) {
	return ((Component) source).getBounds();
	} else {
	return null;
	}
	}

	/**
	* Sets the current bounds of this object.
	*/
	public void setBounds(Rectangle r) {
	if (source instanceof Component) {
	((Component) source).setBounds(r);
	}
	}

	/**
	* Returns the current size of this object.
	*
	* @return current size of object; can be null if this object is
	* not on the screen
	*/
	public Dimension getSize() {
	if (source instanceof Component) {
	return ((Component) source).getSize();
	} else {
	return null;
	}
	}

	/**
	* Sets the current size of this object.
	*/
	public void setSize(Dimension d) {
	if (source instanceof Component) {
	((Component) source).setSize(d);
	}
	}

	/**
	* Returns the accessible child contained at the local coordinate
	* Point, if one exists.
	*
	* @return the Accessible at the specified location, if it exists
	*/
	public Accessible getAccessibleAt(Point p) {
	if (source instanceof Component) {
	Component c = ((Component) source).getComponentAt(p);
	if (c != null) {
	return (getAccessible(c));
	}
	}
	return null;
	}

	/**
	* Returns whether this object can accept focus or not.
	*
	* @return true if object can accept focus; otherwise false
	*/
	public boolean isFocusTraversable() {
	if (source instanceof Component) {
	return ((Component) source).isFocusTraversable();
	} else {
	return false;
	}
	}

	/**
	* Requests focus for this object.
	*/
	public void requestFocus() {
	if (source instanceof Component) {
	((Component) source).requestFocus();
	}
	}

	/**
	* Adds the specified {@code FocusListener} to receive focus events from
	* this component.
	*
	* @param l the focus listener
	*/
	public synchronized void addFocusListener(FocusListener l) {
	if (source instanceof Component) {
	((Component) source).addFocusListener(l);
	}
	}

	/**
	* Removes the specified focus listener so it no longer receives focus
	* events from this component.
	*
	* @param l the focus listener; this method performs no function, nor does it
	* throw an exception if the listener specified was not previously added
	* to this component; if listener is null, no exception is thrown and no
	* action is performed.
	*/
	public synchronized void removeFocusListener(FocusListener l) {
	if (source instanceof Component) {
	((Component) source).removeFocusListener(l);
	}
	}
	}

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