1 /*
   2  * Copyright (c) 2011, 2013, 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 
  26 package com.sun.javafx.property.adapter;
  27 
  28 import javafx.beans.WeakListener;
  29 import javafx.beans.property.adapter.ReadOnlyJavaBeanProperty;
  30 
  31 import java.beans.PropertyChangeEvent;
  32 import java.beans.PropertyChangeListener;
  33 import java.lang.ref.WeakReference;
  34 import java.lang.reflect.InvocationTargetException;
  35 import java.lang.reflect.Method;
  36 
  37 import sun.reflect.misc.ReflectUtil;
  38 
  39 import static java.util.Locale.ENGLISH;
  40 
  41 /**
  42  */
  43 public class ReadOnlyPropertyDescriptor {
  44 
  45     private static final String ADD_LISTENER_METHOD_NAME = "addPropertyChangeListener";
  46     private static final String REMOVE_LISTENER_METHOD_NAME = "removePropertyChangeListener";
  47     private static final String ADD_PREFIX = "add";
  48     private static final String REMOVE_PREFIX = "remove";
  49     private static final String SUFFIX = "Listener";
  50 
  51     private static final int ADD_LISTENER_TAKES_NAME = 1;
  52     private static final int REMOVE_LISTENER_TAKES_NAME = 2;
  53 
  54     protected final String name;
  55     protected final Class<?> beanClass;
  56     private final Method getter;
  57     private final Class<?> type;
  58 
  59     private final Method addChangeListener;
  60     private final Method removeChangeListener;
  61     private final int flags;
  62 
  63     public String getName() {return name;}
  64     public Method getGetter() {return getter;}
  65     public Class<?> getType() {return type;}
  66 
  67     public ReadOnlyPropertyDescriptor(String propertyName, Class<?> beanClass, Method getter) {
  68         ReflectUtil.checkPackageAccess(beanClass);
  69 
  70         this.name = propertyName;
  71         this.beanClass = beanClass;
  72         this.getter = getter;
  73         this.type = getter.getReturnType();
  74 
  75         Method tmpAddChangeListener = null;
  76         Method tmpRemoveChangeListener = null;
  77         int tmpFlags = 0;
  78 
  79         try {
  80             final String methodName = ADD_PREFIX + capitalizedName(name) + SUFFIX;
  81             tmpAddChangeListener = beanClass.getMethod(methodName, PropertyChangeListener.class);
  82         } catch (NoSuchMethodException e) {
  83             try {
  84                 tmpAddChangeListener = beanClass.getMethod(ADD_LISTENER_METHOD_NAME, String.class, PropertyChangeListener.class);
  85                 tmpFlags |= ADD_LISTENER_TAKES_NAME;
  86             } catch (NoSuchMethodException e1) {
  87                 try {
  88                     tmpAddChangeListener = beanClass.getMethod(ADD_LISTENER_METHOD_NAME, PropertyChangeListener.class);
  89                 } catch (NoSuchMethodException e2) {
  90                     // ignore
  91                 }
  92             }
  93         }
  94 
  95         try {
  96             final String methodName = REMOVE_PREFIX + capitalizedName(name) + SUFFIX;
  97             tmpRemoveChangeListener = beanClass.getMethod(methodName, PropertyChangeListener.class);
  98         } catch (NoSuchMethodException e) {
  99             try {
 100                 tmpRemoveChangeListener = beanClass.getMethod(REMOVE_LISTENER_METHOD_NAME, String.class, PropertyChangeListener.class);
 101                 tmpFlags |= REMOVE_LISTENER_TAKES_NAME;
 102             } catch (NoSuchMethodException e1) {
 103                 try {
 104                     tmpRemoveChangeListener = beanClass.getMethod(REMOVE_LISTENER_METHOD_NAME, PropertyChangeListener.class);
 105                 } catch (NoSuchMethodException e2) {
 106                     // ignore
 107                 }
 108             }
 109         }
 110 
 111         addChangeListener = tmpAddChangeListener;
 112         removeChangeListener = tmpRemoveChangeListener;
 113         flags = tmpFlags;
 114     }
 115 
 116     public static String capitalizedName(String name) {
 117         return ((name == null) || (name.length() == 0))? name : name.substring(0, 1).toUpperCase(ENGLISH) + name.substring(1);
 118     }
 119 
 120     public void addListener(ReadOnlyListener listener) {
 121         if (addChangeListener != null) {
 122             try {
 123                 if ((flags & ADD_LISTENER_TAKES_NAME) > 0) {
 124                     addChangeListener.invoke(listener.getBean(), name, listener);
 125                 } else {
 126                     addChangeListener.invoke(listener.getBean(), listener);
 127                 }
 128             } catch (IllegalAccessException e) {
 129                 // ignore
 130             } catch (InvocationTargetException e) {
 131                 // ignore
 132             }
 133         }
 134     }
 135 
 136     public void removeListener(ReadOnlyListener listener) {
 137         if (removeChangeListener != null) {
 138             try {
 139                 if ((flags & REMOVE_LISTENER_TAKES_NAME) > 0) {
 140                     removeChangeListener.invoke(listener.getBean(), name, listener);
 141                 } else {
 142                     removeChangeListener.invoke(listener.getBean(), listener);
 143                 }
 144             } catch (IllegalAccessException e) {
 145                 // ignore
 146             } catch (InvocationTargetException e) {
 147                 // ignore
 148             }
 149         }
 150     }
 151 
 152     public class ReadOnlyListener<T> implements PropertyChangeListener, WeakListener {
 153 
 154         protected final Object bean;
 155         private final WeakReference<ReadOnlyJavaBeanProperty<T>> propertyRef;
 156 
 157         public Object getBean() {return bean;}
 158 
 159         public ReadOnlyListener(Object bean, ReadOnlyJavaBeanProperty<T> property) {
 160             this.bean = bean;
 161             this.propertyRef = new WeakReference<ReadOnlyJavaBeanProperty<T>>(property);
 162         }
 163 
 164         protected ReadOnlyJavaBeanProperty<T> checkRef() {
 165             final ReadOnlyJavaBeanProperty<T> result = propertyRef.get();
 166             if (result == null) {
 167                 removeListener(this);
 168             }
 169             return result;
 170         }
 171 
 172         @Override
 173         public void propertyChange(PropertyChangeEvent propertyChangeEvent) {
 174             if (bean.equals(propertyChangeEvent.getSource()) && name.equals(propertyChangeEvent.getPropertyName())) {
 175                 final ReadOnlyJavaBeanProperty<T> property = checkRef();
 176                 if (property != null) {
 177                     property.fireValueChangedEvent();
 178                 }
 179             }
 180         }
 181 
 182         @Override
 183         public boolean wasGarbageCollected() {
 184             return checkRef() == null;
 185         }
 186     }
 187 }