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Diffstat (limited to 'libjava/java/beans/VetoableChangeSupport.java')
| -rw-r--r-- | libjava/java/beans/VetoableChangeSupport.java | 530 |
1 files changed, 0 insertions, 530 deletions
diff --git a/libjava/java/beans/VetoableChangeSupport.java b/libjava/java/beans/VetoableChangeSupport.java deleted file mode 100644 index dce8dffd341..00000000000 --- a/libjava/java/beans/VetoableChangeSupport.java +++ /dev/null @@ -1,530 +0,0 @@ -/* VetoableChangeSupport.java -- support to manage vetoable change listeners - Copyright (C) 1998, 1999, 2000, 2002, 2005 Free Software Foundation, Inc. - -This file is part of GNU Classpath. - -GNU Classpath is free software; you can redistribute it and/or modify -it under the terms of the GNU General Public License as published by -the Free Software Foundation; either version 2, or (at your option) -any later version. - -GNU Classpath 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 for more details. - -You should have received a copy of the GNU General Public License -along with GNU Classpath; see the file COPYING. If not, write to the -Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA -02110-1301 USA. - -Linking this library statically or dynamically with other modules is -making a combined work based on this library. Thus, the terms and -conditions of the GNU General Public License cover the whole -combination. - -As a special exception, the copyright holders of this library give you -permission to link this library with independent modules to produce an -executable, regardless of the license terms of these independent -modules, and to copy and distribute the resulting executable under -terms of your choice, provided that you also meet, for each linked -independent module, the terms and conditions of the license of that -module. An independent module is a module which is not derived from -or based on this library. If you modify this library, you may extend -this exception to your version of the library, but you are not -obligated to do so. If you do not wish to do so, delete this -exception statement from your version. */ - - -package java.beans; - -import java.io.IOException; -import java.io.ObjectInputStream; -import java.io.ObjectOutputStream; -import java.io.Serializable; -import java.util.ArrayList; -import java.util.Arrays; -import java.util.Hashtable; -import java.util.Iterator; -import java.util.Map.Entry; -import java.util.Vector; - -/** - * VetoableChangeSupport makes it easy to fire vetoable change events and - * handle listeners. It allows chaining of listeners, as well as filtering - * by property name. In addition, it will serialize only those listeners - * which are serializable, ignoring the others without problem. This class - * is thread-safe. - * - * @author John Keiser - * @author Eric Blake (ebb9@email.byu.edu) - * @since 1.1 - * @status updated to 1.4 - */ -public class VetoableChangeSupport implements Serializable -{ - /** - * Compatible with JDK 1.1+. - */ - private static final long serialVersionUID = -5090210921595982017L; - - /** - * Maps property names (String) to named listeners (VetoableChangeSupport). - * If this is a child instance, this field will be null. - * - * @serial the map of property names to named listener managers - * @since 1.2 - */ - private Hashtable children; - - /** - * The non-null source object for any generated events. - * - * @serial the event source - */ - private final Object source; - - /** - * A field to compare serialization versions - this class uses version 2. - * - * @serial the serialization format - */ - private static final int vetoableChangeSupportSerializedDataVersion = 2; - - /** - * The list of all registered vetoable listeners. If this instance was - * created by user code, this only holds the global listeners (ie. not tied - * to a name), and may be null. If it was created by this class, as a - * helper for named properties, then this vector will be non-null, and this - * instance appears as a value in the <code>children</code> hashtable of - * another instance, so that the listeners are tied to the key of that - * hashtable entry. - */ - private transient Vector listeners; - - /** - * Create a VetoableChangeSupport to work with a specific source bean. - * - * @param source the source bean to use - * @throws NullPointerException if source is null - */ - public VetoableChangeSupport(Object source) - { - this.source = source; - if (source == null) - throw new NullPointerException(); - } - - /** - * Adds a VetoableChangeListener to the list of global listeners. All - * vetoable change events will be sent to this listener. The listener add - * is not unique: that is, <em>n</em> adds with the same listener will - * result in <em>n</em> events being sent to that listener for every - * vetoable change. Adding a null listener may cause a NullPointerException - * down the road. This method will unwrap a VetoableChangeListenerProxy, - * registering the underlying delegate to the named property list. - * - * @param l the listener to add - */ - public synchronized void addVetoableChangeListener(VetoableChangeListener l) - { - if (l instanceof VetoableChangeListenerProxy) - { - VetoableChangeListenerProxy p = (VetoableChangeListenerProxy) l; - addVetoableChangeListener(p.propertyName, - (VetoableChangeListener) p.getListener()); - } - else - { - if (listeners == null) - listeners = new Vector(); - listeners.add(l); - } - } - - /** - * Removes a VetoableChangeListener from the list of global listeners. If - * any specific properties are being listened on, they must be deregistered - * by themselves; this will only remove the general listener to all - * properties. If <code>add()</code> has been called multiple times for a - * particular listener, <code>remove()</code> will have to be called the - * same number of times to deregister it. This method will unwrap a - * VetoableChangeListenerProxy, removing the underlying delegate from the - * named property list. - * - * @param l the listener to remove - */ - public synchronized void - removeVetoableChangeListener(VetoableChangeListener l) - { - if (l instanceof VetoableChangeListenerProxy) - { - VetoableChangeListenerProxy p = (VetoableChangeListenerProxy) l; - removeVetoableChangeListener(p.propertyName, - (VetoableChangeListener) p.getListener()); - } - else if (listeners != null) - { - listeners.remove(l); - if (listeners.isEmpty()) - listeners = null; - } - } - - /** - * Returns an array of all registered vetoable change listeners. Those that - * were registered under a name will be wrapped in a - * <code>VetoableChangeListenerProxy</code>, so you must check whether the - * listener is an instance of the proxy class in order to see what name the - * real listener is registered under. If there are no registered listeners, - * this returns an empty array. - * - * @return the array of registered listeners - * @see VetoableChangeListenerProxy - * @since 1.4 - */ - public synchronized VetoableChangeListener[] getVetoableChangeListeners() - { - ArrayList list = new ArrayList(); - if (listeners != null) - list.addAll(listeners); - if (children != null) - { - int i = children.size(); - Iterator iter = children.entrySet().iterator(); - while (--i >= 0) - { - Entry e = (Entry) iter.next(); - String name = (String) e.getKey(); - Vector v = ((VetoableChangeSupport) e.getValue()).listeners; - int j = v.size(); - while (--j >= 0) - list.add(new VetoableChangeListenerProxy - (name, (VetoableChangeListener) v.get(j))); - } - } - return (VetoableChangeListener[]) - list.toArray(new VetoableChangeListener[list.size()]); - } - - /** - * Adds a VetoableChangeListener listening on the specified property. Events - * will be sent to the listener only if the property name matches. The - * listener add is not unique; that is, <em>n</em> adds on a particular - * property for a particular listener will result in <em>n</em> events - * being sent to that listener when that property is changed. The effect is - * cumulative, too; if you are registered to listen to receive events on - * all vetoable changes, and then you register on a particular property, - * you will receive change events for that property twice. Adding a null - * listener may cause a NullPointerException down the road. This method - * will unwrap a VetoableChangeListenerProxy, registering the underlying - * delegate to the named property list if the names match, and discarding - * it otherwise. - * - * @param propertyName the name of the property to listen on - * @param l the listener to add - * @throws NullPointerException if propertyName is null - */ - public synchronized void addVetoableChangeListener(String propertyName, - VetoableChangeListener l) - { - while (l instanceof VetoableChangeListenerProxy) - { - VetoableChangeListenerProxy p = (VetoableChangeListenerProxy) l; - if (propertyName == null ? p.propertyName != null - : ! propertyName.equals(p.propertyName)) - return; - l = (VetoableChangeListener) p.getListener(); - } - VetoableChangeSupport s = null; - if (children == null) - children = new Hashtable(); - else - s = (VetoableChangeSupport) children.get(propertyName); - if (s == null) - { - s = new VetoableChangeSupport(source); - s.listeners = new Vector(); - children.put(propertyName, s); - } - s.listeners.add(l); - } - - /** - * Removes a VetoableChangeListener from listening to a specific property. - * If <code>add()</code> has been called multiple times for a particular - * listener on a property, <code>remove()</code> will have to be called the - * same number of times to deregister it. This method will unwrap a - * VetoableChangeListenerProxy, removing the underlying delegate from the - * named property list if the names match. - * - * @param propertyName the property to stop listening on - * @param l the listener to remove - * @throws NullPointerException if propertyName is null - */ - public synchronized void - removeVetoableChangeListener(String propertyName, VetoableChangeListener l) - { - if (children == null) - return; - VetoableChangeSupport s - = (VetoableChangeSupport) children.get(propertyName); - if (s == null) - return; - while (l instanceof VetoableChangeListenerProxy) - { - VetoableChangeListenerProxy p = (VetoableChangeListenerProxy) l; - if (propertyName == null ? p.propertyName != null - : ! propertyName.equals(p.propertyName)) - return; - l = (VetoableChangeListener) p.getListener(); - } - s.listeners.remove(l); - if (s.listeners.isEmpty()) - { - children.remove(propertyName); - if (children.isEmpty()) - children = null; - } - } - - /** - * Returns an array of all vetoable change listeners registered under the - * given property name. If there are no registered listeners, this returns - * an empty array. - * - * @return the array of registered listeners - * @throws NullPointerException if propertyName is null - * @since 1.4 - */ - public synchronized VetoableChangeListener[] - getVetoableChangeListeners(String propertyName) - { - if (children == null) - return new VetoableChangeListener[0]; - VetoableChangeSupport s - = (VetoableChangeSupport) children.get(propertyName); - if (s == null) - return new VetoableChangeListener[0]; - return (VetoableChangeListener[]) - s.listeners.toArray(new VetoableChangeListener[s.listeners.size()]); - } - - /** - * Fire a PropertyChangeEvent containing the old and new values of the - * property to all the global listeners, and to all the listeners for the - * specified property name. This does nothing if old and new are non-null - * and equal. If the change is vetoed, a new event is fired to notify - * listeners about the rollback before the exception is thrown. - * - * @param propertyName the name of the property that changed - * @param oldVal the old value - * @param newVal the new value - * @throws PropertyVetoException if the change is vetoed by a listener - */ - public void fireVetoableChange(String propertyName, - Object oldVal, Object newVal) - throws PropertyVetoException - { - fireVetoableChange(new PropertyChangeEvent(source, propertyName, - oldVal, newVal)); - } - - /** - * Fire a PropertyChangeEvent containing the old and new values of the - * property to all the global listeners, and to all the listeners for the - * specified property name. This does nothing if old and new are equal. - * If the change is vetoed, a new event is fired to notify listeners about - * the rollback before the exception is thrown. - * - * @param propertyName the name of the property that changed - * @param oldVal the old value - * @param newVal the new value - * @throws PropertyVetoException if the change is vetoed by a listener - */ - public void fireVetoableChange(String propertyName, int oldVal, int newVal) - throws PropertyVetoException - { - if (oldVal != newVal) - fireVetoableChange(new PropertyChangeEvent(source, propertyName, - new Integer(oldVal), - new Integer(newVal))); - } - - /** - * Fire a PropertyChangeEvent containing the old and new values of the - * property to all the global listeners, and to all the listeners for the - * specified property name. This does nothing if old and new are equal. - * If the change is vetoed, a new event is fired to notify listeners about - * the rollback before the exception is thrown. - * - * @param propertyName the name of the property that changed - * @param oldVal the old value - * @param newVal the new value - * @throws PropertyVetoException if the change is vetoed by a listener - */ - public void fireVetoableChange(String propertyName, - boolean oldVal, boolean newVal) - throws PropertyVetoException - { - if (oldVal != newVal) - fireVetoableChange(new PropertyChangeEvent(source, propertyName, - Boolean.valueOf(oldVal), - Boolean.valueOf(newVal))); - } - - /** - * Fire a PropertyChangeEvent to all the global listeners, and to all the - * listeners for the specified property name. This does nothing if old and - * new values of the event are equal. If the change is vetoed, a new event - * is fired to notify listeners about the rollback before the exception is - * thrown. - * - * @param event the event to fire - * @throws NullPointerException if event is null - * @throws PropertyVetoException if the change is vetoed by a listener - */ - public void fireVetoableChange(PropertyChangeEvent event) - throws PropertyVetoException - { - if (event.oldValue != null && event.oldValue.equals(event.newValue)) - return; - Vector v = listeners; // Be thread-safe. - if (v != null) - { - int i = v.size(); - try - { - while (--i >= 0) - ((VetoableChangeListener) v.get(i)).vetoableChange(event); - } - catch (PropertyVetoException e) - { - event = event.rollback(); - int limit = i; - i = v.size(); - while (--i >= limit) - ((VetoableChangeListener) v.get(i)).vetoableChange(event); - throw e; - } - } - Hashtable h = children; // Be thread-safe. - if (h != null && event.propertyName != null) - { - VetoableChangeSupport s - = (VetoableChangeSupport) h.get(event.propertyName); - if (s != null) - { - Vector v1 = s.listeners; // Be thread-safe. - int i = v1 == null ? 0 : v1.size(); - try - { - while (--i >= 0) - ((VetoableChangeListener) v1.get(i)).vetoableChange(event); - } - catch (PropertyVetoException e) - { - event = event.rollback(); - int limit = i; - i = v.size(); - while (--i >= 0) - ((VetoableChangeListener) v.get(i)).vetoableChange(event); - i = v1.size(); - while (--i >= limit) - ((VetoableChangeListener) v1.get(i)).vetoableChange(event); - throw e; - } - } - } - } - - /** - * Tell whether the specified property is being listened on or not. This - * will only return <code>true</code> if there are listeners on all - * properties or if there is a listener specifically on this property. - * - * @param propertyName the property that may be listened on - * @return whether the property is being listened on - * @throws NullPointerException if propertyName is null - */ - public synchronized boolean hasListeners(String propertyName) - { - return listeners != null || (children != null - && children.get(propertyName) != null); - } - - /** - * Saves the state of the object to the stream. - * - * @param s the stream to write to - * @throws IOException if anything goes wrong - * @serialData this writes out a null-terminated list of serializable - * global vetoable change listeners (the listeners for a named - * property are written out as the global listeners of the - * children, when the children hashtable is saved) - */ - private synchronized void writeObject(ObjectOutputStream s) - throws IOException - { - s.defaultWriteObject(); - if (listeners != null) - { - int i = listeners.size(); - while (--i >= 0) - if (listeners.get(i) instanceof Serializable) - s.writeObject(listeners.get(i)); - } - s.writeObject(null); - } - - /** - * Reads the object back from stream (deserialization). - * - * XXX Since serialization for 1.1 streams was not documented, this may - * not work if vetoableChangeSupportSerializedDataVersion is 1. - * - * @param s the stream to read from - * @throws IOException if reading the stream fails - * @throws ClassNotFoundException if deserialization fails - * @serialData this reads in a null-terminated list of serializable - * global vetoable change listeners (the listeners for a named - * property are written out as the global listeners of the - * children, when the children hashtable is saved) - */ - private void readObject(ObjectInputStream s) - throws IOException, ClassNotFoundException - { - s.defaultReadObject(); - VetoableChangeListener l = (VetoableChangeListener) s.readObject(); - while (l != null) - { - addVetoableChangeListener(l); - l = (VetoableChangeListener) s.readObject(); - } - // Sun is not as careful with children as we are, and lets some proxys - // in that can never receive events. So, we clean up anything that got - // serialized, to make sure our invariants hold. - if (children != null) - { - int i = children.size(); - Iterator iter = children.entrySet().iterator(); - while (--i >= 0) - { - Entry e = (Entry) iter.next(); - String name = (String) e.getKey(); - VetoableChangeSupport vcs = (VetoableChangeSupport) e.getValue(); - if (vcs.listeners == null) - vcs.listeners = new Vector(); - if (vcs.children != null) - vcs.listeners.addAll - (Arrays.asList(vcs.getVetoableChangeListeners(name))); - if (vcs.listeners.size() == 0) - iter.remove(); - else - vcs.children = null; - } - if (children.size() == 0) - children = null; - } - } -} // class VetoableChangeSupport |
