/*
* @(#)VetoableChangeSupport.java 1.47 06/10/10
*
* Copyright 1990-2008 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER
*
* This program 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.
*
* This program 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 at /legal/license.txt).
*
* 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 Sun Microsystems, Inc., 4150 Network Circle, Santa
* Clara, CA 95054 or visit www.sun.com if you need additional
* information or have any questions.
*
*/
package java.beans;
import java.io.Serializable;
import java.io.ObjectOutputStream;
import java.io.ObjectInputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
/**
* This is a utility class that can be used by beans that support constrained
* properties. You can use an instance of this class as a member field
* of your bean and delegate various work to it.
*
* 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.
*/
public class VetoableChangeSupport implements java.io.Serializable {
/**
* Constructs a <code>VetoableChangeSupport</code> object.
*
* @param sourceBean The bean to be given as the source for any events.
*/
public VetoableChangeSupport(Object sourceBean) {
if (sourceBean == null) {
throw new NullPointerException();
}
source = sourceBean;
}
/**
* Add a VetoableListener to the listener list.
* The listener is registered for all properties.
*
* @param listener The VetoableChangeListener to be added
*/
public synchronized void addVetoableChangeListener(
VetoableChangeListener listener) {
if (listeners == null) {
listeners = new java.util.Vector();
}
listeners.addElement(listener);
}
/**
* Remove a VetoableChangeListener from the listener list.
* This removes a PropertyChangeListener that was registered
* for all properties.
*
* @param listener The VetoableChangeListener to be removed
*/
public synchronized void removeVetoableChangeListener(
VetoableChangeListener listener) {
if (listeners == null) {
return;
}
listeners.removeElement(listener);
}
/**
* Add a VetoableChangeListener for a specific property. The listener
* will be invoked only when a call on fireVetoableChange names that
* specific property.
*
* @param propertyName The name of the property to listen on.
* @param listener The VetoableChangeListener to be added
*/
/* public synchronized void addVetoableChangeListener(
String propertyName,
VetoableChangeListener listener) {
if (children == null) {
children = new java.util.Hashtable();
}
VetoableChangeSupport child = (VetoableChangeSupport)children.get(propertyName);
if (child == null) {
child = new VetoableChangeSupport(source);
children.put(propertyName, child);
}
child.addVetoableChangeListener(listener);
}
*/
/**
* Remove a VetoableChangeListener for a specific property.
*
* @param propertyName The name of the property that was listened on.
* @param listener The VetoableChangeListener to be removed
*/
/* public synchronized void removeVetoableChangeListener(
String propertyName,
VetoableChangeListener listener) {
if (children == null) {
return;
}
VetoableChangeSupport child = (VetoableChangeSupport)children.get(propertyName);
if (child == null) {
return;
}
child.removeVetoableChangeListener(listener);
}
*/
/**
* Report a vetoable property update to any registered listeners. If
* anyone vetos the change, then fire a new event reverting everyone to
* the old value and then rethrow the PropertyVetoException.
* <p>
* No event is fired if old and new are equal and non-null.
*
* @param propertyName The programmatic name of the property
* that is about to change..
* @param oldValue The old value of the property.
* @param newValue The new value of the property.
* @exception PropertyVetoException if the recipient wishes the property
* change to be rolled back.
*/
public void fireVetoableChange(String propertyName,
Object oldValue, Object newValue)
throws PropertyVetoException {
if (listeners == null && children == null) {
return;
}
PropertyChangeEvent evt = new PropertyChangeEvent(source, propertyName,
oldValue, newValue);
fireVetoableChange(evt);
}
/**
* Report a int vetoable property update to any registered listeners.
* No event is fired if old and new are equal and non-null.
* <p>
* This is merely a convenience wrapper around the more general
* fireVetoableChange method that takes Object values.
*
* @param propertyName The programmatic name of the property
* that is about to change.
* @param oldValue The old value of the property.
* @param newValue The new value of the property.
*/
/* public void fireVetoableChange(String propertyName,
int oldValue, int newValue)
throws PropertyVetoException {
if (oldValue == newValue) {
return;
}
fireVetoableChange(propertyName, new Integer(oldValue), new Integer(newValue));
}
*/
/**
* Report a boolean vetoable property update to any registered listeners.
* No event is fired if old and new are equal and non-null.
* <p>
* This is merely a convenience wrapper around the more general
* fireVetoableChange method that takes Object values.
*
* @param propertyName The programmatic name of the property
* that is about to change.
* @param oldValue The old value of the property.
* @param newValue The new value of the property.
*/
/* public void fireVetoableChange(String propertyName,
boolean oldValue, boolean newValue)
throws PropertyVetoException {
if (oldValue == newValue) {
return;
}
fireVetoableChange(propertyName, new Boolean(oldValue), new Boolean(newValue));
}
*/
/**
* Fire a vetoable property update to any registered listeners. If
* anyone vetos the change, then fire a new event reverting everyone to
* the old value and then rethrow the PropertyVetoException.
* <p>
* No event is fired if old and new are equal and non-null.
*
* @param evt The PropertyChangeEvent to be fired.
* @exception PropertyVetoException if the recipient wishes the property
* change to be rolled back.
*/
private void fireVetoableChange(PropertyChangeEvent evt)
throws PropertyVetoException {
Object oldValue = evt.getOldValue();
Object newValue = evt.getNewValue();
String propertyName = evt.getPropertyName();
if (oldValue != null && newValue != null && oldValue.equals(newValue)) {
return;
}
java.util.Vector targets = null;
VetoableChangeSupport child = null;
synchronized (this) {
if (listeners != null) {
targets = (java.util.Vector) listeners.clone();
}
if (children != null && propertyName != null) {
child = (VetoableChangeSupport) children.get(propertyName);
}
}
if (listeners != null) {
try {
for (int i = 0; i < targets.size(); i++) {
VetoableChangeListener target =
(VetoableChangeListener) targets.elementAt(i);
target.vetoableChange(evt);
}
} catch (PropertyVetoException veto) {
// Create an event to revert everyone to the old value.
evt = new PropertyChangeEvent(source, propertyName, newValue, oldValue);
for (int i = 0; i < targets.size(); i++) {
try {
VetoableChangeListener target =
(VetoableChangeListener) targets.elementAt(i);
target.vetoableChange(evt);
} catch (PropertyVetoException ex) {// We just ignore exceptions that occur during reversions.
}
}
// And now rethrow the PropertyVetoException.
throw veto;
}
}
if (child != null) {
child.fireVetoableChange(evt);
}
}
/**
* Check if there are any listeners for a specific property.
*
* @param propertyName the property name.
* @return true if there are one or more listeners for the given property
*/
/* public synchronized boolean hasListeners(String propertyName) {
if (listeners != null && !listeners.isEmpty()) {
// there is a generic listener
return true;
}
if (children != null) {
VetoableChangeSupport child = (VetoableChangeSupport)children.get(propertyName);
if (child != null && child.listeners != null) {
return !child.listeners.isEmpty();
}
}
return false;
}
*/
/**
* @serialData Null terminated list of <code>VetoableChangeListeners</code>.
* <p>
* At serialization time we skip non-serializable listeners and
* only serialize the serializable listeners.
*
*/
private void writeObject(ObjectOutputStream s) throws IOException {
s.defaultWriteObject();
java.util.Vector v = null;
synchronized (this) {
if (listeners != null) {
v = (java.util.Vector) listeners.clone();
}
}
if (v != null) {
for (int i = 0; i < v.size(); i++) {
VetoableChangeListener l = (VetoableChangeListener) v.elementAt(i);
if (l instanceof Serializable) {
s.writeObject(l);
}
}
}
s.writeObject(null);
}
private void readObject(ObjectInputStream s) throws ClassNotFoundException, IOException {
s.defaultReadObject();
Object listenerOrNull;
while (null != (listenerOrNull = s.readObject())) {
addVetoableChangeListener((VetoableChangeListener) listenerOrNull);
}
}
/**
* "listeners" lists all the generic listeners.
*
* This is transient - its state is written in the writeObject method.
*/
transient private java.util.Vector listeners;
/**
* Hashtable for managing listeners for specific properties.
* Maps property names to VetoableChangeSupport objects.
* @serial
* @since 1.2
*/
private java.util.Hashtable children;
/**
* The object to be provided as the "source" for any generated events.
* @serial
*/
private Object source;
/**
* Internal version number
* @serial
*/
private int vetoableChangeSupportSerializedDataVersion = 2;
/**
* Serialization version ID, so we're compatible with JDK 1.1
*/
static final long serialVersionUID = -5090210921595982017L;
// Focus-related functionality added
//-------------------------------------------------------------------------
public synchronized VetoableChangeListener[] getVetoableChangeListeners(){
List returnList = new ArrayList();
// Add all the VetoableChangeListeners
if (listeners != null) {
returnList.addAll(listeners);
}
return (VetoableChangeListener[])(returnList.toArray
(new VetoableChangeListener[0]));
}
/*
public synchronized VetoableChangeListener[] getVetoableChangeListeners(
String propertyName) {
List returnList = new ArrayList();
if (children != null) {
VetoableChangeSupport support =
(VetoableChangeSupport)children.get(propertyName);
if (support != null) {
returnList.addAll(
Arrays.asList(support.getVetoableChangeListeners()));
}
}
return (VetoableChangeListener[])(returnList.toArray
(new VetoableChangeListener[0]));
}
public void fireVetoableChange(String propertyName,
int oldValue, int newValue)
throws PropertyVetoException {
if (oldValue == newValue) {
return;
}
fireVetoableChange(propertyName, new Integer(oldValue), new Integer(newValue));
}
public void fireVetoableChange(String propertyName,
boolean oldValue, boolean newValue)
throws PropertyVetoException {
if (oldValue == newValue) {
return;
}
fireVetoableChange(propertyName, new Boolean(oldValue), new Boolean(newValue));
}
public synchronized void addVetoableChangeListener(
String propertyName,
VetoableChangeListener listener) {
if (children == null) {
children = new java.util.Hashtable();
}
VetoableChangeSupport child = (VetoableChangeSupport)children.get(propertyName);
if (child == null) {
child = new VetoableChangeSupport(source);
children.put(propertyName, child);
}
child.addVetoableChangeListener(listener);
}
public synchronized void removeVetoableChangeListener(
String propertyName,
VetoableChangeListener listener) {
if (children == null) {
return;
}
VetoableChangeSupport child = (VetoableChangeSupport)children.get(propertyName);
if (child == null) {
return;
}
child.removeVetoableChangeListener(listener);
}
*/
}