/*
 * Copyright (c) 2003, 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 sun.swing;

import java.awt.Color;
import java.awt.Insets;
import javax.swing.*;
import javax.swing.border.Border;
import javax.swing.plaf.ComponentUI;
import sun.awt.AppContext;

/**
 * DefaultLookup provides a way to customize the lookup done by the
 * UIManager. The default implementation of DefaultLookup forwards
 * the call to the UIManager.
 * <p>
 * <b>WARNING:</b> While this class is public, it should not be treated as
 * public API and its API may change in incompatable ways between dot dot
 * releases and even patch releases. You should not rely on this class even
 * existing.
 *
 * @author Scott Violet
 */
public class DefaultLookup {
 /**
 * Key used to store DefaultLookup for AppContext.
 */
 private static final Object DEFAULT_LOOKUP_KEY = new
 StringBuffer("DefaultLookup");
 /**
 * Thread that last asked for a default.
 */
 private static Thread currentDefaultThread;
 /**
 * DefaultLookup for last thread.
 */
 private static DefaultLookup currentDefaultLookup;

 /**
 * If true, a custom DefaultLookup has been set.
 */
 private static boolean isLookupSet;


 /**
 * Sets the DefaultLookup instance to use for the current
 * <code>AppContext</code>. Null implies the UIManager should be
 * used.
 */
 public static void setDefaultLookup(DefaultLookup lookup) {
 synchronized(DefaultLookup.class) {
 if (!isLookupSet && lookup == null) {
 // Null was passed in, and no one has invoked setDefaultLookup
 // with a non-null value, we don't need to do anything.
 return;
 }
 else if (lookup == null) {
 // null was passed in, but someone has invoked setDefaultLookup
 // with a non-null value, use an instance of DefautLookup
 // which will fallback to UIManager.
 lookup = new DefaultLookup();
 }
 isLookupSet = true;
 AppContext.getAppContext().put(DEFAULT_LOOKUP_KEY, lookup);
 currentDefaultThread = Thread.currentThread();
 currentDefaultLookup = lookup;
 }
 }

 public static Object get(JComponent c, ComponentUI ui, String key) {
 boolean lookupSet;
 synchronized(DefaultLookup.class) {
 lookupSet = isLookupSet;
 }
 if (!lookupSet) {
 // No one has set a valid DefaultLookup, use UIManager.
 return UIManager.get(key, c.getLocale());
 }
 Thread thisThread = Thread.currentThread();
 DefaultLookup lookup;
 synchronized(DefaultLookup.class) {
 // See if we've already cached the DefaultLookup for this thread,
 // and use it if we have.
 if (thisThread == currentDefaultThread) {
 // It is cached, use it.
 lookup = currentDefaultLookup;
 }
 else {
 // Not cached, get the DefaultLookup to use from the AppContext
 lookup = (DefaultLookup)AppContext.getAppContext().get(
 DEFAULT_LOOKUP_KEY);
 if (lookup == null) {
 // Fallback to DefaultLookup, which will redirect to the
 // UIManager.
 lookup = new DefaultLookup();
 AppContext.getAppContext().put(DEFAULT_LOOKUP_KEY, lookup);
 }
 // Cache the values to make the next lookup easier.
 currentDefaultThread = thisThread;
 currentDefaultLookup = lookup;
 }
 }
 return lookup.getDefault(c, ui, key);
 }

 //
 // The following are convenience method that all use getDefault.
 //
 public static int getInt(JComponent c, ComponentUI ui, String key,
 int defaultValue) {
 Object iValue = get(c, ui, key);

 if (iValue == null || !(iValue instanceof Number)) {
 return defaultValue;
 }
 return ((Number)iValue).intValue();
 }

 public static int getInt(JComponent c, ComponentUI ui, String key) {
 return getInt(c, ui, key, -1);
 }

 public static Insets getInsets(JComponent c, ComponentUI ui, String key,
 Insets defaultValue) {
 Object iValue = get(c, ui, key);

 if (iValue == null || !(iValue instanceof Insets)) {
 return defaultValue;
 }
 return (Insets)iValue;
 }

 public static Insets getInsets(JComponent c, ComponentUI ui, String key) {
 return getInsets(c, ui, key, null);
 }

 public static boolean getBoolean(JComponent c, ComponentUI ui, String key,
 boolean defaultValue) {
 Object iValue = get(c, ui, key);

 if (iValue == null || !(iValue instanceof Boolean)) {
 return defaultValue;
 }
 return ((Boolean)iValue).booleanValue();
 }

 public static boolean getBoolean(JComponent c, ComponentUI ui, String key) {
 return getBoolean(c, ui, key, false);
 }

 public static Color getColor(JComponent c, ComponentUI ui, String key,
 Color defaultValue) {
 Object iValue = get(c, ui, key);

 if (iValue == null || !(iValue instanceof Color)) {
 return defaultValue;
 }
 return (Color)iValue;
 }

 public static Color getColor(JComponent c, ComponentUI ui, String key) {
 return getColor(c, ui, key, null);
 }

 public static Icon getIcon(JComponent c, ComponentUI ui, String key,
 Icon defaultValue) {
 Object iValue = get(c, ui, key);
 if (iValue == null || !(iValue instanceof Icon)) {
 return defaultValue;
 }
 return (Icon)iValue;
 }

 public static Icon getIcon(JComponent c, ComponentUI ui, String key) {
 return getIcon(c, ui, key, null);
 }

 public static Border getBorder(JComponent c, ComponentUI ui, String key,
 Border defaultValue) {
 Object iValue = get(c, ui, key);
 if (iValue == null || !(iValue instanceof Border)) {
 return defaultValue;
 }
 return (Border)iValue;
 }

 public static Border getBorder(JComponent c, ComponentUI ui, String key) {
 return getBorder(c, ui, key, null);
 }

 public Object getDefault(JComponent c, ComponentUI ui, String key) {
 // basic
 return UIManager.get(key, c.getLocale());
 }
}