1 /*
   2  * Copyright (c) 2002, 2014, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 package javax.swing.plaf.basic;
  26 
  27 import java.lang.reflect.*;
  28 import javax.swing.*;
  29 import javax.swing.plaf.*;
  30 
  31 /**
  32  * An ActionMap that populates its contents as necessary. The
  33  * contents are populated by invoking the <code>loadActionMap</code>
  34  * method on the passed in Object.
  35  *
  36  * @author Scott Violet
  37  */
  38 @SuppressWarnings("serial") // Same-version serialization only
  39 class LazyActionMap extends ActionMapUIResource {
  40     /**
  41      * Object to invoke <code>loadActionMap</code> on. This may be
  42      * a Class object.
  43      */
  44     private transient Object _loader;
  45 
  46     /**
  47      * Installs an ActionMap that will be populated by invoking the
  48      * <code>loadActionMap</code> method on the specified Class
  49      * when necessary.
  50      * <p>
  51      * This should be used if the ActionMap can be shared.
  52      *
  53      * @param c JComponent to install the ActionMap on.
  54      * @param loaderClass Class object that gets loadActionMap invoked
  55      *                    on.
  56      * @param defaultsKey Key to use to defaults table to check for
  57      *        existing map and what resulting Map will be registered on.
  58      */
  59     static void installLazyActionMap(JComponent c, Class loaderClass,
  60                                      String defaultsKey) {
  61         ActionMap map = (ActionMap)UIManager.get(defaultsKey);
  62         if (map == null) {
  63             map = new LazyActionMap(loaderClass);
  64             UIManager.getLookAndFeelDefaults().put(defaultsKey, map);
  65         }
  66         SwingUtilities.replaceUIActionMap(c, map);
  67     }
  68 
  69     /**
  70      * Returns an ActionMap that will be populated by invoking the
  71      * <code>loadActionMap</code> method on the specified Class
  72      * when necessary.
  73      * <p>
  74      * This should be used if the ActionMap can be shared.
  75      *
  76      * @param c JComponent to install the ActionMap on.
  77      * @param loaderClass Class object that gets loadActionMap invoked
  78      *                    on.
  79      * @param defaultsKey Key to use to defaults table to check for
  80      *        existing map and what resulting Map will be registered on.
  81      */
  82     static ActionMap getActionMap(Class loaderClass,
  83                                   String defaultsKey) {
  84         ActionMap map = (ActionMap)UIManager.get(defaultsKey);
  85         if (map == null) {
  86             map = new LazyActionMap(loaderClass);
  87             UIManager.getLookAndFeelDefaults().put(defaultsKey, map);
  88         }
  89         return map;
  90     }
  91 
  92 
  93     private LazyActionMap(Class loader) {
  94         _loader = loader;
  95     }
  96 
  97     public void put(Action action) {
  98         put(action.getValue(Action.NAME), action);
  99     }
 100 
 101     public void put(Object key, Action action) {
 102         loadIfNecessary();
 103         super.put(key, action);
 104     }
 105 
 106     public Action get(Object key) {
 107         loadIfNecessary();
 108         return super.get(key);
 109     }
 110 
 111     public void remove(Object key) {
 112         loadIfNecessary();
 113         super.remove(key);
 114     }
 115 
 116     public void clear() {
 117         loadIfNecessary();
 118         super.clear();
 119     }
 120 
 121     public Object[] keys() {
 122         loadIfNecessary();
 123         return super.keys();
 124     }
 125 
 126     public int size() {
 127         loadIfNecessary();
 128         return super.size();
 129     }
 130 
 131     public Object[] allKeys() {
 132         loadIfNecessary();
 133         return super.allKeys();
 134     }
 135 
 136     public void setParent(ActionMap map) {
 137         loadIfNecessary();
 138         super.setParent(map);
 139     }
 140 
 141     private void loadIfNecessary() {
 142         if (_loader != null) {
 143             Object loader = _loader;
 144 
 145             _loader = null;
 146             Class<?> klass = (Class<?>)loader;
 147             try {
 148                 Method method = klass.getDeclaredMethod("loadActionMap",
 149                                       new Class[] { LazyActionMap.class });
 150                 method.invoke(klass, new Object[] { this });
 151             } catch (NoSuchMethodException nsme) {
 152                 assert false : "LazyActionMap unable to load actions " +
 153                         klass;
 154             } catch (IllegalAccessException iae) {
 155                 assert false : "LazyActionMap unable to load actions " +
 156                         iae;
 157             } catch (InvocationTargetException ite) {
 158                 assert false : "LazyActionMap unable to load actions " +
 159                         ite;
 160             } catch (IllegalArgumentException iae) {
 161                 assert false : "LazyActionMap unable to load actions " +
 162                         iae;
 163             }
 164         }
 165     }
 166 }