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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.awt.Font;
	import java.awt.event.InputEvent;
	import java.awt.event.KeyEvent;
	import java.awt.Color;
	import java.awt.Component;
	import java.awt.SystemColor;
	import java.awt.Toolkit;
	import sun.awt.SunToolkit;

	import javax.swing.text.*;
	import javax.swing.border.*;
	import javax.swing.plaf.*;

	import java.net.URL;
	import sun.swing.SwingUtilities2;
	import sun.swing.DefaultLayoutStyle;
	import sun.swing.ImageIconUIResource;

	import java.util.StringTokenizer;


	/**
	* {@code LookAndFeel}, as the name implies, encapsulates a look and
	* feel. Beyond installing a look and feel most developers never need to
	* interact directly with {@code LookAndFeel}. In general only developers
	* creating a custom look and feel need to concern themselves with this class.
	* <p>
	* Swing is built upon the foundation that each {@code JComponent}
	* subclass has an implementation of a specific {@code ComponentUI}
	* subclass. The {@code ComponentUI} is often referred to as "the ui",
	* "component ui", or "look and feel delegate". The {@code ComponentUI}
	* subclass is responsible for providing the look and feel specific
	* functionality of the component. For example, {@code JTree} requires
	* an implementation of the {@code ComponentUI} subclass {@code
	* TreeUI}. The implementation of the specific {@code
	* ComponentUI} subclass is provided by the {@code LookAndFeel}. Each
	* {@code JComponent} subclass identifies the {@code ComponentUI}
	* subclass it requires by way of the {@code JComponent} method {@code
	* getUIClassID}.
	* <p>
	* Each {@code LookAndFeel} implementation must provide
	* an implementation of the appropriate {@code ComponentUI} subclass by
	* specifying a value for each of Swing's ui class ids in the {@code
	* UIDefaults} object returned from {@code getDefaults}. For example,
	* {@code BasicLookAndFeel} uses {@code BasicTreeUI} as the concrete
	* implementation for {@code TreeUI}. This is accomplished by {@code
	* BasicLookAndFeel} providing the key-value pair {@code
	* "TreeUI"-"javax.swing.plaf.basic.BasicTreeUI"}, in the
	* {@code UIDefaults} returned from {@code getDefaults}. Refer to
	* {@link UIDefaults#getUI(JComponent)} for details on how the implementation
	* of the {@code ComponentUI} subclass is obtained.
	* <p>
	* When a {@code LookAndFeel} is installed the {@code UIManager} does
	* not check that an entry exists for all ui class ids. As such,
	* random exceptions will occur if the current look and feel has not
	* provided a value for a particular ui class id and an instance of
	* the {@code JComponent} subclass is created.
	*
	* <h2>Recommendations for Look and Feels</h2>
	*
	* As noted in {@code UIManager} each {@code LookAndFeel} has the opportunity
	* to provide a set of defaults that are layered in with developer and
	* system defaults. Some of Swing's components require the look and feel
	* to provide a specific set of defaults. These are documented in the
	* classes that require the specific default.
	*
	* <h3><a name="defaultRecommendation">ComponentUIs and defaults</a></h3>
	*
	* All {@code ComponentUIs} typically need to set various properties
	* on the {@code JComponent} the {@code ComponentUI} is providing the
	* look and feel for. This is typically done when the {@code
	* ComponentUI} is installed on the {@code JComponent}. Setting a
	* property should only be done if the developer has not set the
	* property. For non-primitive values it is recommended that the
	* {@code ComponentUI} only change the property on the {@code
	* JComponent} if the current value is {@code null} or implements
	* {@code UIResource}. If the current value is {@code null} or
	* implements {@code UIResource} it indicates the property has not
	* been set by the developer, and the ui is free to change it. For
	* example, {@code BasicButtonUI.installDefaults} only changes the
	* font on the {@code JButton} if the return value from {@code
	* button.getFont()} is {@code null} or implements {@code
	* UIResource}. On the other hand if {@code button.getFont()} returned
	* a {@code non-null} value that did not implement {@code UIResource}
	* then {@code BasicButtonUI.installDefaults} would not change the
	* {@code JButton}'s font.
	* <p>
	* For primitive values, such as {@code opaque}, the method {@code
	* installProperty} should be invoked. {@code installProperty} only changes
	* the corresponding property if the value has not been changed by the
	* developer.
	* <p>
	* {@code ComponentUI} implementations should use the various install methods
	* provided by this class as they handle the necessary checking and install
	* the property using the recommended guidelines.
	*
	* <h3><a name="exceptions"></a>Exceptions</h3>
	*
	* All of the install methods provided by {@code LookAndFeel} need to
	* access the defaults if the value of the property being changed is
	* {@code null} or a {@code UIResource}. For example, installing the
	* font does the following:
	* <pre>
	* JComponent c;
	* Font font = c.getFont();
	* if (font == null \|\| (font instanceof UIResource)) {
	* c.setFont(UIManager.getFont("fontKey"));
	* }
	* </pre>
	* If the font is {@code null} or a {@code UIResource}, the
	* defaults table is queried with the key {@code fontKey}. All of
	* {@code UIDefault's} get methods throw a {@code
	* NullPointerException} if passed in {@code null}. As such, unless
	* otherwise noted each of the various install methods of {@code
	* LookAndFeel} throw a {@code NullPointerException} if the current
	* value is {@code null} or a {@code UIResource} and the supplied
	* defaults key is {@code null}. In addition, unless otherwise specified
	* all of the {@code install} methods throw a {@code NullPointerException} if
	* a {@code null} component is passed in.
	*
	* @author Tom Ball
	* @author Hans Muller
	*/
	public abstract class LookAndFeel
	{

	/**
	* Convenience method for setting a component's foreground
	* and background color properties with values from the
	* defaults. The properties are only set if the current
	* value is either {@code null} or a {@code UIResource}.
	*
	* @param c component to set the colors on
	* @param defaultBgName key for the background
	* @param defaultFgName key for the foreground
	*
	* @see #installColorsAndFont
	* @see UIManager#getColor
	* @throws NullPointerException as described in
	* <a href="#exceptions">exceptions</a>
	*/
	public static void installColors(JComponent c,
	String defaultBgName,
	String defaultFgName)
	{
	Color bg = c.getBackground();
	if (bg == null \|\| bg instanceof UIResource) {
	c.setBackground(UIManager.getColor(defaultBgName));
	}

	Color fg = c.getForeground();
	if (fg == null \|\| fg instanceof UIResource) {
	c.setForeground(UIManager.getColor(defaultFgName));
	}
	}


	/**
	* Convenience method for setting a component's foreground,
	* background and font properties with values from the
	* defaults. The properties are only set if the current
	* value is either {@code null} or a {@code UIResource}.
	*
	* @param c component set to the colors and font on
	* @param defaultBgName key for the background
	* @param defaultFgName key for the foreground
	* @param defaultFontName key for the font
	* @throws NullPointerException as described in
	* <a href="#exceptions">exceptions</a>
	*
	* @see #installColors
	* @see UIManager#getColor
	* @see UIManager#getFont
	*/
	public static void installColorsAndFont(JComponent c,
	String defaultBgName,
	String defaultFgName,
	String defaultFontName) {
	Font f = c.getFont();
	if (f == null \|\| f instanceof UIResource) {
	c.setFont(UIManager.getFont(defaultFontName));
	}

	installColors(c, defaultBgName, defaultFgName);
	}


	/**
	* Convenience method for setting a component's border property with
	* a value from the defaults. The border is only set if the border is
	* {@code null} or an instance of {@code UIResource}.
	*
	* @param c component to set the border on
	* @param defaultBorderName key specifying the border
	* @throws NullPointerException as described in
	* <a href="#exceptions">exceptions</a>
	*/
	public static void installBorder(JComponent c, String defaultBorderName) {
	Border b = c.getBorder();
	if (b == null \|\| b instanceof UIResource) {
	c.setBorder(UIManager.getBorder(defaultBorderName));
	}
	}


	/**
	* Convenience method for uninstalling a border. If the border of
	* the component is a {@code UIResource}, it is set to {@code
	* null}.
	*
	* @param c component to uninstall the border on
	* @throws NullPointerException if {@code c} is {@code null}
	*/
	public static void uninstallBorder(JComponent c) {
	if (c.getBorder() instanceof UIResource) {
	c.setBorder(null);
	}
	}

	/**
	* Convenience method for installing a property with the specified name
	* and value on a component if that property has not already been set
	* by the developer. This method is intended to be used by
	* ui delegate instances that need to specify a default value for a
	* property of primitive type (boolean, int, ..), but do not wish
	* to override a value set by the client. Since primitive property
	* values cannot be wrapped with the {@code UIResource} marker, this method
	* uses private state to determine whether the property has been set
	* by the client.
	*
	* @throws IllegalArgumentException if the specified property is not
	* one which can be set using this method
	* @throws ClassCastException if the property value has not been set
	* by the developer and the type does not match the property's type
	* @throws NullPointerException if {@code c} is {@code null}, or the
	* named property has not been set by the developer and
	* {@code propertyValue} is {@code null}
	* @param c target component to set the property on
	* @param propertyName name of the property to set
	* @param propertyValue value of the property
	* @since 1.5
	*/
	public static void installProperty(JComponent c,
	String propertyName, Object propertyValue) {
	// this is a special case because the JPasswordField's ancestor hierarchy
	// includes a class outside of javax.swing, thus we cannot call setUIProperty
	// directly.
	if (SunToolkit.isInstanceOf(c, "javax.swing.JPasswordField")) {
	if (!((JPasswordField)c).customSetUIProperty(propertyName, propertyValue)) {
	c.setUIProperty(propertyName, propertyValue);
	}
	} else {
	c.setUIProperty(propertyName, propertyValue);
	}
	}

	/**
	* Convenience method for building an array of {@code
	* KeyBindings}. While this method is not deprecated, developers
	* should instead use {@code ActionMap} and {@code InputMap} for
	* supplying key bindings.
	* <p>
	* This method returns an array of {@code KeyBindings}, one for each
	* alternating {@code key-action} pair in {@code keyBindingList}.
	* A {@code key} can either be a {@code String} in the format
	* specified by the <code>KeyStroke.getKeyStroke</code> method, or
	* a {@code KeyStroke}. The {@code action} part of the pair is a
	* {@code String} that corresponds to the name of the {@code
	* Action}.
	* <p>
	* The following example illustrates creating a {@code KeyBinding} array
	* from six alternating {@code key-action} pairs:
	* <pre>
	* JTextComponent.KeyBinding[] multilineBindings = makeKeyBindings( new Object[] {
	* "UP", DefaultEditorKit.upAction,
	* "DOWN", DefaultEditorKit.downAction,
	* "PAGE_UP", DefaultEditorKit.pageUpAction,
	* "PAGE_DOWN", DefaultEditorKit.pageDownAction,
	* "ENTER", DefaultEditorKit.insertBreakAction,
	* "TAB", DefaultEditorKit.insertTabAction
	* });
	* </pre>
	* If {@code keyBindingList's} length is odd, the last element is
	* ignored.
	* <p>
	* Supplying a {@code null} value for either the {@code key} or
	* {@code action} part of the {@code key-action} pair results in
	* creating a {@code KeyBinding} with the corresponding value
	* {@code null}. As other parts of Swing's expect {@code non-null} values
	* in a {@code KeyBinding}, you should avoid supplying {@code null} as
	* either the {@code key} or {@code action} part of the {@code key-action}
	* pair.
	*
	* @param keyBindingList an array of {@code key-action} pairs
	* @return an array of {@code KeyBindings}
	* @throws NullPointerException if {@code keyBindingList} is {@code null}
	* @throws ClassCastException if the {@code key} part of the pair is
	* not a {@code KeyStroke} or {@code String}, or the
	* {@code action} part of the pair is not a {@code String}
	* @see ActionMap
	* @see InputMap
	* @see KeyStroke#getKeyStroke
	*/
	public static JTextComponent.KeyBinding[] makeKeyBindings(Object[] keyBindingList)
	{
	JTextComponent.KeyBinding[] rv = new JTextComponent.KeyBinding[keyBindingList.length / 2];

	for(int i = 0; i < rv.length; i ++) {
	Object o = keyBindingList[2 * i];
	KeyStroke keystroke = (o instanceof KeyStroke)
	? (KeyStroke) o
	: KeyStroke.getKeyStroke((String) o);
	String action = (String) keyBindingList[2 * i + 1];
	rv[i] = new JTextComponent.KeyBinding(keystroke, action);
	}

	return rv;
	}

	/**
	* Creates a {@code InputMapUIResource} from <code>keys</code>. This is
	* a convenience method for creating a new {@code InputMapUIResource},
	* invoking {@code loadKeyBindings(map, keys)}, and returning the
	* {@code InputMapUIResource}.
	*
	* @param keys alternating pairs of {@code keystroke-action key}
	* pairs as described in {@link #loadKeyBindings}
	* @return newly created and populated {@code InputMapUIResource}
	* @see #loadKeyBindings
	*
	* @since 1.3
	*/
	public static InputMap makeInputMap(Object[] keys) {
	InputMap retMap = new InputMapUIResource();
	loadKeyBindings(retMap, keys);
	return retMap;
	}

	/**
	* Creates a {@code ComponentInputMapUIResource} from
	* <code>keys</code>. This is a convenience method for creating a
	* new {@code ComponentInputMapUIResource}, invoking {@code
	* loadKeyBindings(map, keys)}, and returning the {@code
	* ComponentInputMapUIResource}.
	*
	* @param c component to create the {@code ComponentInputMapUIResource}
	* with
	* @param keys alternating pairs of {@code keystroke-action key}
	* pairs as described in {@link #loadKeyBindings}
	* @return newly created and populated {@code InputMapUIResource}
	* @throws IllegalArgumentException if {@code c} is {@code null}
	*
	* @see #loadKeyBindings
	* @see ComponentInputMapUIResource
	*
	* @since 1.3
	*/
	public static ComponentInputMap makeComponentInputMap(JComponent c,
	Object[] keys) {
	ComponentInputMap retMap = new ComponentInputMapUIResource(c);
	loadKeyBindings(retMap, keys);
	return retMap;
	}


	/**
	* Populates an {@code InputMap} with the specified bindings.
	* The bindings are supplied as a list of alternating
	* {@code keystroke-action key} pairs. The {@code keystroke} is either
	* an instance of {@code KeyStroke}, or a {@code String}
	* that identifies the {@code KeyStroke} for the binding. Refer
	* to {@code KeyStroke.getKeyStroke(String)} for the specific
	* format. The {@code action key} part of the pair is the key
	* registered in the {@code InputMap} for the {@code KeyStroke}.
	* <p>
	* The following illustrates loading an {@code InputMap} with two
	* {@code key-action} pairs:
	* <pre>
	* LookAndFeel.loadKeyBindings(inputMap, new Object[] {
	* "control X", "cut",
	* "control V", "paste"
	* });
	* </pre>
	* <p>
	* Supplying a {@code null} list of bindings ({@code keys}) does not
	* change {@code retMap} in any way.
	* <p>
	* Specifying a {@code null} {@code action key} results in
	* removing the {@code keystroke's} entry from the {@code InputMap}.
	* A {@code null} {@code keystroke} is ignored.
	*
	* @param retMap {@code InputMap} to add the {@code key-action}
	* pairs to
	* @param keys bindings to add to {@code retMap}
	* @throws NullPointerException if {@code keys} is
	* {@code non-null}, not empty, and {@code retMap} is
	* {@code null}
	*
	* @see KeyStroke#getKeyStroke(String)
	* @see InputMap
	*
	* @since 1.3
	*/
	public static void loadKeyBindings(InputMap retMap, Object[] keys) {
	if (keys != null) {
	for (int counter = 0, maxCounter = keys.length;
	counter < maxCounter; counter++) {
	Object keyStrokeO = keys[counter++];
	KeyStroke ks = (keyStrokeO instanceof KeyStroke) ?
	(KeyStroke)keyStrokeO :
	KeyStroke.getKeyStroke((String)keyStrokeO);
	retMap.put(ks, keys[counter]);
	}
	}
	}

	/**
	* Creates and returns a {@code UIDefault.LazyValue} that loads an
	* image. The returned value is an implementation of {@code
	* UIDefaults.LazyValue}. When {@code createValue} is invoked on
	* the returned object, the image is loaded. If the image is {@code
	* non-null}, it is then wrapped in an {@code Icon} that implements {@code
	* UIResource}. The image is loaded using {@code
	* Class.getResourceAsStream(gifFile)}.
	* <p>
	* This method does not check the arguments in any way. It is
	* strongly recommended that {@code non-null} values are supplied else
	* exceptions may occur when {@code createValue} is invoked on the
	* returned object.
	*
	* @param baseClass {@code Class} used to load the resource
	* @param gifFile path to the image to load
	* @return a {@code UIDefaults.LazyValue}; when resolved the
	* {@code LazyValue} loads the specified image
	* @see UIDefaults.LazyValue
	* @see Icon
	* @see Class#getResourceAsStream(String)
	*/
	public static Object makeIcon(final Class<?> baseClass, final String gifFile) {
	return SwingUtilities2.makeIcon(baseClass, baseClass, gifFile);
	}

	/**
	* Returns the <code>LayoutStyle</code> for this look
	* and feel. This never returns {@code null}.
	* <p>
	* You generally don't use the <code>LayoutStyle</code> from
	* the look and feel, instead use the <code>LayoutStyle</code>
	* method <code>getInstance</code>.
	*
	* @see LayoutStyle#getInstance
	* @return the <code>LayoutStyle</code> for this look and feel
	* @since 1.6
	*/
	public LayoutStyle getLayoutStyle() {
	return DefaultLayoutStyle.getInstance();
	}

	/**
	* Invoked when the user attempts an invalid operation,
	* such as pasting into an uneditable <code>JTextField</code>
	* that has focus. The default implementation beeps. Subclasses
	* that wish different behavior should override this and provide
	* the additional feedback.
	*
	* @param component the <code>Component</code> the error occurred in,
	* may be <code>null</code>
	* indicating the error condition is not directly
	* associated with a <code>Component</code>
	* @since 1.4
	*/
	public void provideErrorFeedback(Component component) {
	Toolkit toolkit = null;
	if (component != null) {
	toolkit = component.getToolkit();
	} else {
	toolkit = Toolkit.getDefaultToolkit();
	}
	toolkit.beep();
	} // provideErrorFeedback()

	/**
	* Returns the value of the specified system desktop property by
	* invoking <code>Toolkit.getDefaultToolkit().getDesktopProperty()</code>.
	* If the value of the specified property is {@code null},
	* {@code fallbackValue} is returned.
	*
	* @param systemPropertyName the name of the system desktop property being queried
	* @param fallbackValue the object to be returned as the value if the system value is null
	* @return the current value of the desktop property
	*
	* @see java.awt.Toolkit#getDesktopProperty
	*
	* @since 1.4
	*/
	public static Object getDesktopPropertyValue(String systemPropertyName, Object fallbackValue) {
	Object value = Toolkit.getDefaultToolkit().getDesktopProperty(systemPropertyName);
	if (value == null) {
	return fallbackValue;
	} else if (value instanceof Color) {
	return new ColorUIResource((Color)value);
	} else if (value instanceof Font) {
	return new FontUIResource((Font)value);
	}
	return value;
	}

	/**
	* Returns an <code>Icon</code> with a disabled appearance.
	* This method is used to generate a disabled <code>Icon</code> when
	* one has not been specified. For example, if you create a
	* <code>JButton</code> and only specify an <code>Icon</code> via
	* <code>setIcon</code> this method will be called to generate the
	* disabled <code>Icon</code>. If {@code null} is passed as
	* <code>icon</code> this method returns {@code null}.
	* <p>
	* Some look and feels might not render the disabled {@code Icon}, in which
	* case they will ignore this.
	*
	* @param component {@code JComponent} that will display the {@code Icon},
	* may be {@code null}
	* @param icon {@code Icon} to generate the disabled icon from
	* @return disabled {@code Icon}, or {@code null} if a suitable
	* {@code Icon} can not be generated
	* @since 1.5
	*/
	public Icon getDisabledIcon(JComponent component, Icon icon) {
	if (icon instanceof ImageIcon) {
	return new ImageIconUIResource(GrayFilter.
	createDisabledImage(((ImageIcon)icon).getImage()));
	}
	return null;
	}

	/**
	* Returns an <code>Icon</code> for use by disabled
	* components that are also selected. This method is used to generate an
	* <code>Icon</code> for components that are in both the disabled and
	* selected states but do not have a specific <code>Icon</code> for this
	* state. For example, if you create a <code>JButton</code> and only
	* specify an <code>Icon</code> via <code>setIcon</code> this method
	* will be called to generate the disabled and selected
	* <code>Icon</code>. If {@code null} is passed as <code>icon</code> this
	* methods returns {@code null}.
	* <p>
	* Some look and feels might not render the disabled and selected
	* {@code Icon}, in which case they will ignore this.
	*
	* @param component {@code JComponent} that will display the {@code Icon},
	* may be {@code null}
	* @param icon {@code Icon} to generate disabled and selected icon from
	* @return disabled and selected icon, or {@code null} if a suitable
	* {@code Icon} can not be generated.
	* @since 1.5
	*/
	public Icon getDisabledSelectedIcon(JComponent component, Icon icon) {
	return getDisabledIcon(component, icon);
	}

	/**
	* Return a short string that identifies this look and feel, e.g.
	* "CDE/Motif". This string should be appropriate for a menu item.
	* Distinct look and feels should have different names, e.g.
	* a subclass of MotifLookAndFeel that changes the way a few components
	* are rendered should be called "CDE/Motif My Way"; something
	* that would be useful to a user trying to select a L&F from a list
	* of names.
	*
	* @return short identifier for the look and feel
	*/
	public abstract String getName();


	/**
	* Return a string that identifies this look and feel. This string
	* will be used by applications/services that want to recognize
	* well known look and feel implementations. Presently
	* the well known names are "Motif", "Windows", "Mac", "Metal". Note
	* that a LookAndFeel derived from a well known superclass
	* that doesn't make any fundamental changes to the look or feel
	* shouldn't override this method.
	*
	* @return identifier for the look and feel
	*/
	public abstract String getID();


	/**
	* Return a one line description of this look and feel implementation,
	* e.g. "The CDE/Motif Look and Feel". This string is intended for
	* the user, e.g. in the title of a window or in a ToolTip message.
	*
	* @return short description for the look and feel
	*/
	public abstract String getDescription();


	/**
	* Returns {@code true} if the <code>LookAndFeel</code> returned
	* <code>RootPaneUI</code> instances support providing {@code Window}
	* decorations in a <code>JRootPane</code>.
	* <p>
	* The default implementation returns {@code false}, subclasses that
	* support {@code Window} decorations should override this and return
	* {@code true}.
	*
	* @return {@code true} if the {@code RootPaneUI} instances created by
	* this look and feel support client side decorations
	* @see JDialog#setDefaultLookAndFeelDecorated
	* @see JFrame#setDefaultLookAndFeelDecorated
	* @see JRootPane#setWindowDecorationStyle
	* @since 1.4
	*/
	public boolean getSupportsWindowDecorations() {
	return false;
	}

	/**
	* If the underlying platform has a "native" look and feel, and
	* this is an implementation of it, return {@code true}. For
	* example, when the underlying platform is Solaris running CDE
	* a CDE/Motif look and feel implementation would return {@code
	* true}.
	*
	* @return {@code true} if this look and feel represents the underlying
	* platform look and feel
	*/
	public abstract boolean isNativeLookAndFeel();


	/**
	* Return {@code true} if the underlying platform supports and or permits
	* this look and feel. This method returns {@code false} if the look
	* and feel depends on special resources or legal agreements that
	* aren't defined for the current platform.
	*
	*
	* @return {@code true} if this is a supported look and feel
	* @see UIManager#setLookAndFeel
	*/
	public abstract boolean isSupportedLookAndFeel();


	/**
	* Initializes the look and feel. While this method is public,
	* it should only be invoked by the {@code UIManager} when a
	* look and feel is installed as the current look and feel. This
	* method is invoked before the {@code UIManager} invokes
	* {@code getDefaults}. This method is intended to perform any
	* initialization for the look and feel. Subclasses
	* should do any one-time setup they need here, rather than
	* in a static initializer, because look and feel class objects
	* may be loaded just to discover that {@code isSupportedLookAndFeel()}
	* returns {@code false}.
	*
	* @see #uninitialize
	* @see UIManager#setLookAndFeel
	*/
	public void initialize() {
	}


	/**
	* Uninitializes the look and feel. While this method is public,
	* it should only be invoked by the {@code UIManager} when
	* the look and feel is uninstalled. For example,
	* {@code UIManager.setLookAndFeel} invokes this when the look and
	* feel is changed.
	* <p>
	* Subclasses may choose to free up some resources here.
	*
	* @see #initialize
	* @see UIManager#setLookAndFeel
	*/
	public void uninitialize() {
	}

	/**
	* Returns the look and feel defaults. While this method is public,
	* it should only be invoked by the {@code UIManager} when the
	* look and feel is set as the current look and feel and after
	* {@code initialize} has been invoked.
	*
	* @return the look and feel defaults
	* @see #initialize
	* @see #uninitialize
	* @see UIManager#setLookAndFeel
	*/
	public UIDefaults getDefaults() {
	return null;
	}

	/**
	* Returns a string that displays and identifies this
	* object's properties.
	*
	* @return a String representation of this object
	*/
	public String toString() {
	return "[" + getDescription() + " - " + getClass().getName() + "]";
	}
	}

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