| /* |
| * Copyright (c) 1996, 2013, 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 java.beans; |
| |
| import java.io.Serializable; |
| import java.io.ObjectStreamField; |
| import java.io.ObjectOutputStream; |
| import java.io.ObjectInputStream; |
| import java.io.IOException; |
| import java.util.Hashtable; |
| import java.util.Map.Entry; |
| |
| /** |
| * This is a utility class that can be used by beans that support bound |
| * properties. It manages a list of listeners and dispatches |
| * {@link PropertyChangeEvent}s to them. You can use an instance of this class |
| * as a member field of your bean and delegate these types of work to it. |
| * The {@link PropertyChangeListener} can be registered for all properties |
| * or for a property specified by name. |
| * <p> |
| * Here is an example of {@code PropertyChangeSupport} usage that follows |
| * the rules and recommendations laid out in the JavaBeans™ specification: |
| * <pre> |
| * public class MyBean { |
| * private final PropertyChangeSupport pcs = new PropertyChangeSupport(this); |
| * |
| * public void addPropertyChangeListener(PropertyChangeListener listener) { |
| * this.pcs.addPropertyChangeListener(listener); |
| * } |
| * |
| * public void removePropertyChangeListener(PropertyChangeListener listener) { |
| * this.pcs.removePropertyChangeListener(listener); |
| * } |
| * |
| * private String value; |
| * |
| * public String getValue() { |
| * return this.value; |
| * } |
| * |
| * public void setValue(String newValue) { |
| * String oldValue = this.value; |
| * this.value = newValue; |
| * this.pcs.firePropertyChange("value", oldValue, newValue); |
| * } |
| * |
| * [...] |
| * } |
| * </pre> |
| * <p> |
| * A {@code PropertyChangeSupport} instance is thread-safe. |
| * <p> |
| * This class is serializable. When it is serialized it will save |
| * (and restore) any listeners that are themselves serializable. Any |
| * non-serializable listeners will be skipped during serialization. |
| * |
| * @see VetoableChangeSupport |
| * @since 1.1 |
| */ |
| public class PropertyChangeSupport implements Serializable { |
| private PropertyChangeListenerMap map = new PropertyChangeListenerMap(); |
| |
| /** |
| * Constructs a {@code PropertyChangeSupport} object. |
| * |
| * @param sourceBean The bean to be given as the source for any events. |
| */ |
| public PropertyChangeSupport(Object sourceBean) { |
| if (sourceBean == null) { |
| throw new NullPointerException(); |
| } |
| source = sourceBean; |
| } |
| |
| /** |
| * Add a PropertyChangeListener to the listener list. |
| * The listener is registered for all properties. |
| * The same listener object may be added more than once, and will be called |
| * as many times as it is added. |
| * If {@code listener} is null, no exception is thrown and no action |
| * is taken. |
| * |
| * @param listener The PropertyChangeListener to be added |
| */ |
| public void addPropertyChangeListener(PropertyChangeListener listener) { |
| if (listener == null) { |
| return; |
| } |
| if (listener instanceof PropertyChangeListenerProxy) { |
| PropertyChangeListenerProxy proxy = |
| (PropertyChangeListenerProxy)listener; |
| // Call two argument add method. |
| addPropertyChangeListener(proxy.getPropertyName(), |
| proxy.getListener()); |
| } else { |
| this.map.add(null, listener); |
| } |
| } |
| |
| /** |
| * Remove a PropertyChangeListener from the listener list. |
| * This removes a PropertyChangeListener that was registered |
| * for all properties. |
| * If {@code listener} was added more than once to the same event |
| * source, it will be notified one less time after being removed. |
| * If {@code listener} is null, or was never added, no exception is |
| * thrown and no action is taken. |
| * |
| * @param listener The PropertyChangeListener to be removed |
| */ |
| public void removePropertyChangeListener(PropertyChangeListener listener) { |
| if (listener == null) { |
| return; |
| } |
| if (listener instanceof PropertyChangeListenerProxy) { |
| PropertyChangeListenerProxy proxy = |
| (PropertyChangeListenerProxy)listener; |
| // Call two argument remove method. |
| removePropertyChangeListener(proxy.getPropertyName(), |
| proxy.getListener()); |
| } else { |
| this.map.remove(null, listener); |
| } |
| } |
| |
| /** |
| * Returns an array of all the listeners that were added to the |
| * PropertyChangeSupport object with addPropertyChangeListener(). |
| * <p> |
| * If some listeners have been added with a named property, then |
| * the returned array will be a mixture of PropertyChangeListeners |
| * and {@code PropertyChangeListenerProxy}s. If the calling |
| * method is interested in distinguishing the listeners then it must |
| * test each element to see if it's a |
| * {@code PropertyChangeListenerProxy}, perform the cast, and examine |
| * the parameter. |
| * |
| * <pre>{@code |
| * PropertyChangeListener[] listeners = bean.getPropertyChangeListeners(); |
| * for (int i = 0; i < listeners.length; i++) { |
| * if (listeners[i] instanceof PropertyChangeListenerProxy) { |
| * PropertyChangeListenerProxy proxy = |
| * (PropertyChangeListenerProxy)listeners[i]; |
| * if (proxy.getPropertyName().equals("foo")) { |
| * // proxy is a PropertyChangeListener which was associated |
| * // with the property named "foo" |
| * } |
| * } |
| * } |
| * }</pre> |
| * |
| * @see PropertyChangeListenerProxy |
| * @return all of the {@code PropertyChangeListeners} added or an |
| * empty array if no listeners have been added |
| * @since 1.4 |
| */ |
| public PropertyChangeListener[] getPropertyChangeListeners() { |
| return this.map.getListeners(); |
| } |
| |
| /** |
| * Add a PropertyChangeListener for a specific property. The listener |
| * will be invoked only when a call on firePropertyChange names that |
| * specific property. |
| * The same listener object may be added more than once. For each |
| * property, the listener will be invoked the number of times it was added |
| * for that property. |
| * If {@code propertyName} or {@code listener} is null, no |
| * exception is thrown and no action is taken. |
| * |
| * @param propertyName The name of the property to listen on. |
| * @param listener The PropertyChangeListener to be added |
| * @since 1.2 |
| */ |
| public void addPropertyChangeListener( |
| String propertyName, |
| PropertyChangeListener listener) { |
| if (listener == null || propertyName == null) { |
| return; |
| } |
| listener = this.map.extract(listener); |
| if (listener != null) { |
| this.map.add(propertyName, listener); |
| } |
| } |
| |
| /** |
| * Remove a PropertyChangeListener for a specific property. |
| * If {@code listener} was added more than once to the same event |
| * source for the specified property, it will be notified one less time |
| * after being removed. |
| * If {@code propertyName} is null, no exception is thrown and no |
| * action is taken. |
| * If {@code listener} is null, or was never added for the specified |
| * property, no exception is thrown and no action is taken. |
| * |
| * @param propertyName The name of the property that was listened on. |
| * @param listener The PropertyChangeListener to be removed |
| * @since 1.2 |
| */ |
| public void removePropertyChangeListener( |
| String propertyName, |
| PropertyChangeListener listener) { |
| if (listener == null || propertyName == null) { |
| return; |
| } |
| listener = this.map.extract(listener); |
| if (listener != null) { |
| this.map.remove(propertyName, listener); |
| } |
| } |
| |
| /** |
| * Returns an array of all the listeners which have been associated |
| * with the named property. |
| * |
| * @param propertyName The name of the property being listened to |
| * @return all of the {@code PropertyChangeListeners} associated with |
| * the named property. If no such listeners have been added, |
| * or if {@code propertyName} is null, an empty array is |
| * returned. |
| * @since 1.4 |
| */ |
| public PropertyChangeListener[] getPropertyChangeListeners(String propertyName) { |
| return this.map.getListeners(propertyName); |
| } |
| |
| /** |
| * Reports a bound property update to listeners |
| * that have been registered to track updates of |
| * all properties or a property with the specified name. |
| * <p> |
| * No event is fired if old and new values are equal and non-null. |
| * <p> |
| * This is merely a convenience wrapper around the more general |
| * {@link #firePropertyChange(PropertyChangeEvent)} method. |
| * |
| * @param propertyName the programmatic name of the property that was changed |
| * @param oldValue the old value of the property |
| * @param newValue the new value of the property |
| */ |
| public void firePropertyChange(String propertyName, Object oldValue, Object newValue) { |
| if (oldValue == null || newValue == null || !oldValue.equals(newValue)) { |
| firePropertyChange(new PropertyChangeEvent(this.source, propertyName, oldValue, newValue)); |
| } |
| } |
| |
| /** |
| * Reports an integer bound property update to listeners |
| * that have been registered to track updates of |
| * all properties or a property with the specified name. |
| * <p> |
| * No event is fired if old and new values are equal. |
| * <p> |
| * This is merely a convenience wrapper around the more general |
| * {@link #firePropertyChange(String, Object, Object)} method. |
| * |
| * @param propertyName the programmatic name of the property that was changed |
| * @param oldValue the old value of the property |
| * @param newValue the new value of the property |
| * @since 1.2 |
| */ |
| public void firePropertyChange(String propertyName, int oldValue, int newValue) { |
| if (oldValue != newValue) { |
| firePropertyChange(propertyName, Integer.valueOf(oldValue), Integer.valueOf(newValue)); |
| } |
| } |
| |
| /** |
| * Reports a boolean bound property update to listeners |
| * that have been registered to track updates of |
| * all properties or a property with the specified name. |
| * <p> |
| * No event is fired if old and new values are equal. |
| * <p> |
| * This is merely a convenience wrapper around the more general |
| * {@link #firePropertyChange(String, Object, Object)} method. |
| * |
| * @param propertyName the programmatic name of the property that was changed |
| * @param oldValue the old value of the property |
| * @param newValue the new value of the property |
| * @since 1.2 |
| */ |
| public void firePropertyChange(String propertyName, boolean oldValue, boolean newValue) { |
| if (oldValue != newValue) { |
| firePropertyChange(propertyName, Boolean.valueOf(oldValue), Boolean.valueOf(newValue)); |
| } |
| } |
| |
| /** |
| * Fires a property change event to listeners |
| * that have been registered to track updates of |
| * all properties or a property with the specified name. |
| * <p> |
| * No event is fired if the given event's old and new values are equal and non-null. |
| * |
| * @param event the {@code PropertyChangeEvent} to be fired |
| * @since 1.2 |
| */ |
| public void firePropertyChange(PropertyChangeEvent event) { |
| Object oldValue = event.getOldValue(); |
| Object newValue = event.getNewValue(); |
| if (oldValue == null || newValue == null || !oldValue.equals(newValue)) { |
| String name = event.getPropertyName(); |
| |
| PropertyChangeListener[] common = this.map.get(null); |
| PropertyChangeListener[] named = (name != null) |
| ? this.map.get(name) |
| : null; |
| |
| fire(common, event); |
| fire(named, event); |
| } |
| } |
| |
| private static void fire(PropertyChangeListener[] listeners, PropertyChangeEvent event) { |
| if (listeners != null) { |
| for (PropertyChangeListener listener : listeners) { |
| listener.propertyChange(event); |
| } |
| } |
| } |
| |
| /** |
| * Reports a bound indexed property update to listeners |
| * that have been registered to track updates of |
| * all properties or a property with the specified name. |
| * <p> |
| * No event is fired if old and new values are equal and non-null. |
| * <p> |
| * This is merely a convenience wrapper around the more general |
| * {@link #firePropertyChange(PropertyChangeEvent)} method. |
| * |
| * @param propertyName the programmatic name of the property that was changed |
| * @param index the index of the property element that was changed |
| * @param oldValue the old value of the property |
| * @param newValue the new value of the property |
| * @since 1.5 |
| */ |
| public void fireIndexedPropertyChange(String propertyName, int index, Object oldValue, Object newValue) { |
| if (oldValue == null || newValue == null || !oldValue.equals(newValue)) { |
| firePropertyChange(new IndexedPropertyChangeEvent(source, propertyName, oldValue, newValue, index)); |
| } |
| } |
| |
| /** |
| * Reports an integer bound indexed property update to listeners |
| * that have been registered to track updates of |
| * all properties or a property with the specified name. |
| * <p> |
| * No event is fired if old and new values are equal. |
| * <p> |
| * This is merely a convenience wrapper around the more general |
| * {@link #fireIndexedPropertyChange(String, int, Object, Object)} method. |
| * |
| * @param propertyName the programmatic name of the property that was changed |
| * @param index the index of the property element that was changed |
| * @param oldValue the old value of the property |
| * @param newValue the new value of the property |
| * @since 1.5 |
| */ |
| public void fireIndexedPropertyChange(String propertyName, int index, int oldValue, int newValue) { |
| if (oldValue != newValue) { |
| fireIndexedPropertyChange(propertyName, index, Integer.valueOf(oldValue), Integer.valueOf(newValue)); |
| } |
| } |
| |
| /** |
| * Reports a boolean bound indexed property update to listeners |
| * that have been registered to track updates of |
| * all properties or a property with the specified name. |
| * <p> |
| * No event is fired if old and new values are equal. |
| * <p> |
| * This is merely a convenience wrapper around the more general |
| * {@link #fireIndexedPropertyChange(String, int, Object, Object)} method. |
| * |
| * @param propertyName the programmatic name of the property that was changed |
| * @param index the index of the property element that was changed |
| * @param oldValue the old value of the property |
| * @param newValue the new value of the property |
| * @since 1.5 |
| */ |
| public void fireIndexedPropertyChange(String propertyName, int index, boolean oldValue, boolean newValue) { |
| if (oldValue != newValue) { |
| fireIndexedPropertyChange(propertyName, index, Boolean.valueOf(oldValue), Boolean.valueOf(newValue)); |
| } |
| } |
| |
| /** |
| * Check if there are any listeners for a specific property, including |
| * those registered on all properties. If {@code propertyName} |
| * is null, only check for listeners registered on all properties. |
| * |
| * @param propertyName the property name. |
| * @return true if there are one or more listeners for the given property |
| * @since 1.2 |
| */ |
| public boolean hasListeners(String propertyName) { |
| return this.map.hasListeners(propertyName); |
| } |
| |
| /** |
| * @serialData Null terminated list of {@code PropertyChangeListeners}. |
| * <p> |
| * At serialization time we skip non-serializable listeners and |
| * only serialize the serializable listeners. |
| */ |
| private void writeObject(ObjectOutputStream s) throws IOException { |
| Hashtable<String, PropertyChangeSupport> children = null; |
| PropertyChangeListener[] listeners = null; |
| synchronized (this.map) { |
| for (Entry<String, PropertyChangeListener[]> entry : this.map.getEntries()) { |
| String property = entry.getKey(); |
| if (property == null) { |
| listeners = entry.getValue(); |
| } else { |
| if (children == null) { |
| children = new Hashtable<>(); |
| } |
| PropertyChangeSupport pcs = new PropertyChangeSupport(this.source); |
| pcs.map.set(null, entry.getValue()); |
| children.put(property, pcs); |
| } |
| } |
| } |
| ObjectOutputStream.PutField fields = s.putFields(); |
| fields.put("children", children); |
| fields.put("source", this.source); |
| fields.put("propertyChangeSupportSerializedDataVersion", 2); |
| s.writeFields(); |
| |
| if (listeners != null) { |
| for (PropertyChangeListener l : listeners) { |
| if (l instanceof Serializable) { |
| s.writeObject(l); |
| } |
| } |
| } |
| s.writeObject(null); |
| } |
| |
| private void readObject(ObjectInputStream s) throws ClassNotFoundException, IOException { |
| this.map = new PropertyChangeListenerMap(); |
| |
| ObjectInputStream.GetField fields = s.readFields(); |
| |
| @SuppressWarnings("unchecked") |
| Hashtable<String, PropertyChangeSupport> children = (Hashtable<String, PropertyChangeSupport>) fields.get("children", null); |
| this.source = fields.get("source", null); |
| fields.get("propertyChangeSupportSerializedDataVersion", 2); |
| |
| Object listenerOrNull; |
| while (null != (listenerOrNull = s.readObject())) { |
| this.map.add(null, (PropertyChangeListener)listenerOrNull); |
| } |
| if (children != null) { |
| for (Entry<String, PropertyChangeSupport> entry : children.entrySet()) { |
| for (PropertyChangeListener listener : entry.getValue().getPropertyChangeListeners()) { |
| this.map.add(entry.getKey(), listener); |
| } |
| } |
| } |
| } |
| |
| /** |
| * The object to be provided as the "source" for any generated events. |
| */ |
| private Object source; |
| |
| /** |
| * @serialField children Hashtable |
| * @serialField source Object |
| * @serialField propertyChangeSupportSerializedDataVersion int |
| */ |
| private static final ObjectStreamField[] serialPersistentFields = { |
| new ObjectStreamField("children", Hashtable.class), |
| new ObjectStreamField("source", Object.class), |
| new ObjectStreamField("propertyChangeSupportSerializedDataVersion", Integer.TYPE) |
| }; |
| |
| /** |
| * Serialization version ID, so we're compatible with JDK 1.1 |
| */ |
| static final long serialVersionUID = 6401253773779951803L; |
| |
| /** |
| * This is a {@link ChangeListenerMap ChangeListenerMap} implementation |
| * that works with {@link PropertyChangeListener PropertyChangeListener} objects. |
| */ |
| private static final class PropertyChangeListenerMap extends ChangeListenerMap<PropertyChangeListener> { |
| private static final PropertyChangeListener[] EMPTY = {}; |
| |
| /** |
| * Creates an array of {@link PropertyChangeListener PropertyChangeListener} objects. |
| * This method uses the same instance of the empty array |
| * when {@code length} equals {@code 0}. |
| * |
| * @param length the array length |
| * @return an array with specified length |
| */ |
| @Override |
| protected PropertyChangeListener[] newArray(int length) { |
| return (0 < length) |
| ? new PropertyChangeListener[length] |
| : EMPTY; |
| } |
| |
| /** |
| * Creates a {@link PropertyChangeListenerProxy PropertyChangeListenerProxy} |
| * object for the specified property. |
| * |
| * @param name the name of the property to listen on |
| * @param listener the listener to process events |
| * @return a {@code PropertyChangeListenerProxy} object |
| */ |
| @Override |
| protected PropertyChangeListener newProxy(String name, PropertyChangeListener listener) { |
| return new PropertyChangeListenerProxy(name, listener); |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public PropertyChangeListener extract(PropertyChangeListener listener) { |
| while (listener instanceof PropertyChangeListenerProxy) { |
| listener = ((PropertyChangeListenerProxy) listener).getListener(); |
| } |
| return listener; |
| } |
| } |
| } |