1 /*
   2  * Copyright (c) 2011, 2015, 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 javafx.beans.property.adapter;
  27 
  28 import com.sun.javafx.binding.ExpressionHelper;
  29 import com.sun.javafx.property.adapter.Disposer;
  30 import com.sun.javafx.property.adapter.PropertyDescriptor;
  31 import javafx.beans.InvalidationListener;
  32 import javafx.beans.property.DoubleProperty;
  33 import javafx.beans.value.ChangeListener;
  34 import javafx.beans.value.ObservableValue;
  35 
  36 import java.lang.reflect.InvocationTargetException;
  37 import java.lang.reflect.UndeclaredThrowableException;
  38 
  39 import java.security.AccessControlContext;
  40 import java.security.AccessController;
  41 import java.security.PrivilegedAction;
  42 
  43 import sun.reflect.misc.MethodUtil;
  44 
  45 /**
  46  * A {@code JavaBeanDoubleProperty} provides an adapter between a regular
  47  * Java Bean property of type {@code double} or {@code Double} and a JavaFX
  48  * {@code DoubleProperty}. It cannot be created directly, but a
  49  * {@link JavaBeanDoublePropertyBuilder} has to be used.
  50  * <p>
  51  * As a minimum, the Java Bean must implement a getter and a setter for the
  52  * property. If the getter of an instance of this class is called, the property of
  53  * the Java Bean is returned. If the setter is called, the value will be passed
  54  * to the Java Bean property. If the Java Bean property is bound (i.e. it supports
  55  * PropertyChangeListeners), this {@code JavaBeanDoubleProperty} will be
  56  * aware of changes in the Java Bean. Otherwise it can be notified about
  57  * changes by calling {@link #fireValueChangedEvent()}. If the Java Bean property
  58  * is also constrained (i.e. it supports VetoableChangeListeners), this
  59  * {@code JavaBeanDoubleProperty} will reject changes, if it is bound to an
  60  * {@link javafx.beans.value.ObservableValue ObservableValue&lt;Double&gt;}.
  61  *
  62  * @see javafx.beans.property.DoubleProperty
  63  * @see JavaBeanDoublePropertyBuilder
  64  * @since JavaFX 2.1
  65  */
  66 public final class JavaBeanDoubleProperty extends DoubleProperty implements JavaBeanProperty<Number> {
  67 
  68     private final PropertyDescriptor descriptor;
  69     private final PropertyDescriptor.Listener<Number> listener;
  70 
  71     private ObservableValue<? extends Number> observable = null;
  72     private ExpressionHelper<Number> helper = null;
  73 
  74     private final AccessControlContext acc = AccessController.getContext();
  75 
  76     JavaBeanDoubleProperty(PropertyDescriptor descriptor, Object bean) {
  77         this.descriptor = descriptor;
  78         this.listener = descriptor.new Listener<Number>(bean, this);
  79         descriptor.addListener(listener);
  80         Disposer.addRecord(this, new DescriptorListenerCleaner(descriptor, listener));
  81     }
  82 
  83     /**
  84      * {@inheritDoc}
  85      *
  86      * @throws UndeclaredThrowableException if calling the getter of the Java Bean
  87      * property throws an {@code IllegalAccessException} or an
  88      * {@code InvocationTargetException}.
  89      */
  90     @Override
  91     public double get() {
  92         return AccessController.doPrivileged((PrivilegedAction<Double>) () -> {
  93             try {
  94                 return ((Number)MethodUtil.invoke(
  95                     descriptor.getGetter(), getBean(), (Object[])null)).doubleValue();
  96             } catch (IllegalAccessException e) {
  97                 throw new UndeclaredThrowableException(e);
  98             } catch (InvocationTargetException e) {
  99                 throw new UndeclaredThrowableException(e);
 100             }
 101         }, acc);
 102     }
 103 
 104     /**
 105      * {@inheritDoc}
 106      *
 107      * @throws UndeclaredThrowableException if calling the getter of the Java Bean
 108      * property throws an {@code IllegalAccessException} or an
 109      * {@code InvocationTargetException}.
 110      */
 111     @Override
 112     public void set(final double value) {
 113         if (isBound()) {
 114             throw new RuntimeException("A bound value cannot be set.");
 115         }
 116 
 117         AccessController.doPrivileged((PrivilegedAction<Void>) () -> {
 118             try {
 119                 MethodUtil.invoke(descriptor.getSetter(), getBean(), new Object[] {value});
 120                 ExpressionHelper.fireValueChangedEvent(helper);
 121             } catch (IllegalAccessException e) {
 122                 throw new UndeclaredThrowableException(e);
 123             } catch (InvocationTargetException e) {
 124                 throw new UndeclaredThrowableException(e);
 125             }
 126             return null;
 127         }, acc);
 128     }
 129 
 130     /**
 131      * {@inheritDoc}
 132      */
 133     @Override
 134     public void bind(ObservableValue<? extends Number> observable) {
 135         if (observable == null) {
 136             throw new NullPointerException("Cannot bind to null");
 137         }
 138 
 139         if (!observable.equals(this.observable)) {
 140             unbind();
 141             set(observable.getValue().doubleValue());
 142             this.observable = observable;
 143             this.observable.addListener(listener);
 144         }
 145     }
 146 
 147     /**
 148      * {@inheritDoc}
 149      */
 150     @Override
 151     public void unbind() {
 152         if (observable != null) {
 153             observable.removeListener(listener);
 154             observable = null;
 155         }
 156     }
 157 
 158     /**
 159      * {@inheritDoc}
 160      */
 161     @Override
 162     public boolean isBound() {
 163         return observable != null;
 164     }
 165 
 166     /**
 167      * {@inheritDoc}
 168      */
 169     @Override
 170     public Object getBean() {
 171         return listener.getBean();
 172     }
 173 
 174     /**
 175      * {@inheritDoc}
 176      */
 177     @Override
 178     public String getName() {
 179         return descriptor.getName();
 180     }
 181 
 182     /**
 183      * {@inheritDoc}
 184      */
 185     @Override
 186     public void addListener(ChangeListener<? super Number> listener) {
 187         helper = ExpressionHelper.addListener(helper, this, listener);
 188     }
 189 
 190     /**
 191      * {@inheritDoc}
 192      */
 193     @Override
 194     public void removeListener(ChangeListener<? super Number> listener) {
 195         helper = ExpressionHelper.removeListener(helper, listener);
 196     }
 197 
 198     /**
 199      * {@inheritDoc}
 200      */
 201     @Override
 202     public void addListener(InvalidationListener listener) {
 203         helper = ExpressionHelper.addListener(helper, this, listener);
 204     }
 205 
 206     /**
 207      * {@inheritDoc}
 208      */
 209     @Override
 210     public void removeListener(InvalidationListener listener) {
 211         helper = ExpressionHelper.removeListener(helper, listener);
 212     }
 213 
 214     /**
 215      * {@inheritDoc}
 216      */
 217     @Override
 218     public void fireValueChangedEvent() {
 219         ExpressionHelper.fireValueChangedEvent(helper);
 220     }
 221 
 222     /**
 223      * {@inheritDoc}
 224      */
 225     @Override
 226     public void dispose() {
 227         descriptor.removeListener(listener);
 228 
 229     }
 230 
 231     /**
 232      * Returns a string representation of this {@code JavaBeanDoubleProperty} object.
 233      * @return a string representation of this {@code JavaBeanDoubleProperty} object.
 234      */
 235     @Override
 236     public String toString() {
 237         final Object bean = getBean();
 238         final String name = getName();
 239         final StringBuilder result = new StringBuilder("DoubleProperty [");
 240         if (bean != null) {
 241             result.append("bean: ").append(bean).append(", ");
 242         }
 243         if ((name != null) && (!name.equals(""))) {
 244             result.append("name: ").append(name).append(", ");
 245         }
 246         if (isBound()) {
 247             result.append("bound, ");
 248         }
 249         result.append("value: ").append(get());
 250         result.append("]");
 251         return result.toString();
 252     }
 253 }