/*
 * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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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&amp;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() + "]";
 }
}