home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
Chip 1998 November
/
Chip_1998-11_cd.bin
/
tema
/
Cafe
/
main.bin
/
PropertyChangeSupport.java
< prev
next >
Wrap
Text File
|
1997-10-01
|
4KB
|
147 lines
/*
* @(#)PropertyChangeSupport.java 1.12 97/05/26
*
* Copyright (c) 1996 Sun Microsystems, Inc. All Rights Reserved.
*
* This software is the confidential and proprietary information of Sun
* Microsystems, Inc. ("Confidential Information"). You shall not
* disclose such Confidential Information and shall use it only in
* accordance with the terms of the license agreement you entered into
* with Sun.
*
* SUN MAKES NO REPRESENTATIONS OR WARRANTIES ABOUT THE SUITABILITY OF THE
* SOFTWARE, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
* IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
* PURPOSE, OR NON-INFRINGEMENT. SUN SHALL NOT BE LIABLE FOR ANY DAMAGES
* SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR DISTRIBUTING
* THIS SOFTWARE OR ITS DERIVATIVES.
*
* CopyrightVersion bdk_beta
*
*/
package java.beans;
import java.io.Serializable;
import java.io.ObjectOutputStream;
import java.io.ObjectInputStream;
import java.io.IOException;
/**
* This is a utility class that can be used by beans that support bound
* properties. You can use an instance of this class as a member field
* of your bean and delegate various work to it.
*/
public class PropertyChangeSupport implements java.io.Serializable {
/**
* @sourceBean The bean to be given as the source for any events.
*/
public PropertyChangeSupport(Object sourceBean) {
source = sourceBean;
}
/**
* Add a PropertyChangeListener to the listener list.
*
* @param listener The PropertyChangeListener to be added
*/
public synchronized void addPropertyChangeListener(
PropertyChangeListener listener) {
if (listeners == null) {
listeners = new java.util.Vector();
}
listeners.addElement(listener);
}
/**
* Remove a PropertyChangeListener from the listener list.
*
* @param listener The PropertyChangeListener to be removed
*/
public synchronized void removePropertyChangeListener(
PropertyChangeListener listener) {
if (listeners == null) {
return;
}
listeners.removeElement(listener);
}
/**
* Report a bound property update to any registered listeners.
* No event is fired if old and new are equal and non-null.
*
* @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 && oldValue.equals(newValue)) {
return;
}
java.util.Vector targets;
synchronized (this) {
if (listeners == null) {
return;
}
targets = (java.util.Vector) listeners.clone();
}
PropertyChangeEvent evt = new PropertyChangeEvent(source,
propertyName, oldValue, newValue);
for (int i = 0; i < targets.size(); i++) {
PropertyChangeListener target = (PropertyChangeListener)targets.elementAt(i);
target.propertyChange(evt);
}
}
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++) {
PropertyChangeListener l = (PropertyChangeListener)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())) {
addPropertyChangeListener((PropertyChangeListener)listenerOrNull);
}
}
transient private java.util.Vector listeners;
private Object source;
private int propertyChangeSupportSerializedDataVersion = 1;
}