1 /*
   2  * Copyright (c) 2002, 2003, 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 class LazyActionMap extends ActionMapUIResource {
  39     /**
  40      * Object to invoke <code>loadActionMap</code> on. This may be
  41      * a Class object.
  42      */
  43     private transient Object _loader;
  44 
  45     /**
  46      * Installs an ActionMap that will be populated by invoking the
  47      * <code>loadActionMap</code> method on the specified Class
  48      * when necessary.
  49      * <p>
  50      * This should be used if the ActionMap can be shared.
  51      *
  52      * @param c JComponent to install the ActionMap on.
  53      * @param loaderClass Class object that gets loadActionMap invoked
  54      *                    on.
  55      * @param defaultsKey Key to use to defaults table to check for
  56      *        existing map and what resulting Map will be registered on.
  57      */
  58     static void installLazyActionMap(JComponent c, Class loaderClass,
  59                                      String defaultsKey) {
  60         ActionMap map = (ActionMap)UIManager.get(defaultsKey);
  61         if (map == null) {
  62             map = new LazyActionMap(loaderClass);
  63             UIManager.getLookAndFeelDefaults().put(defaultsKey, map);
  64         }
  65         SwingUtilities.replaceUIActionMap(c, map);
  66     }
  67 
  68     /**
  69      * Returns an ActionMap that will be populated by invoking the
  70      * <code>loadActionMap</code> method on the specified Class
  71      * when necessary.
  72      * <p>
  73      * This should be used if the ActionMap can be shared.
  74      *
  75      * @param c JComponent to install the ActionMap on.
  76      * @param loaderClass Class object that gets loadActionMap invoked
  77      *                    on.
  78      * @param defaultsKey Key to use to defaults table to check for
  79      *        existing map and what resulting Map will be registered on.
  80      */
  81     static ActionMap getActionMap(Class loaderClass,
  82                                   String defaultsKey) {
  83         ActionMap map = (ActionMap)UIManager.get(defaultsKey);
  84         if (map == null) {
  85             map = new LazyActionMap(loaderClass);
  86             UIManager.getLookAndFeelDefaults().put(defaultsKey, map);
  87         }
  88         return map;
  89     }
  90 
  91 
  92     private LazyActionMap(Class loader) {
  93         _loader = loader;
  94     }
  95 
  96     public void put(Action action) {
  97         put(action.getValue(Action.NAME), action);
  98     }
  99 
 100     public void put(Object key, Action action) {
 101         loadIfNecessary();
 102         super.put(key, action);
 103     }
 104 
 105     public Action get(Object key) {
 106         loadIfNecessary();
 107         return super.get(key);
 108     }
 109 
 110     public void remove(Object key) {
 111         loadIfNecessary();
 112         super.remove(key);
 113     }
 114 
 115     public void clear() {
 116         loadIfNecessary();
 117         super.clear();
 118     }
 119 
 120     public Object[] keys() {
 121         loadIfNecessary();
 122         return super.keys();
 123     }
 124 
 125     public int size() {
 126         loadIfNecessary();
 127         return super.size();
 128     }
 129 
 130     public Object[] allKeys() {
 131         loadIfNecessary();
 132         return super.allKeys();
 133     }
 134 
 135     public void setParent(ActionMap map) {
 136         loadIfNecessary();
 137         super.setParent(map);
 138     }
 139 
 140     private void loadIfNecessary() {
 141         if (_loader != null) {
 142             Object loader = _loader;
 143 
 144             _loader = null;
 145             Class<?> klass = (Class<?>)loader;
 146             try {
 147                 Method method = klass.getDeclaredMethod("loadActionMap",
 148                                       new Class[] { LazyActionMap.class });
 149                 method.invoke(klass, new Object[] { this });
 150             } catch (NoSuchMethodException nsme) {
 151                 assert false : "LazyActionMap unable to load actions " +
 152                         klass;
 153             } catch (IllegalAccessException iae) {
 154                 assert false : "LazyActionMap unable to load actions " +
 155                         iae;
 156             } catch (InvocationTargetException ite) {
 157                 assert false : "LazyActionMap unable to load actions " +
 158                         ite;
 159             } catch (IllegalArgumentException iae) {
 160                 assert false : "LazyActionMap unable to load actions " +
 161                         iae;
 162             }
 163         }
 164     }
 165 }