mirror of
git://gcc.gnu.org/git/gcc.git
synced 2024-12-24 18:29:27 +08:00
251 lines
9.0 KiB
Java
251 lines
9.0 KiB
Java
/* java.beans.PropertyChangeSupport
|
|
Copyright (C) 1998, 1999, 2000 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., 59 Temple Place, Suite 330, Boston, MA
|
|
02111-1307 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.util.Hashtable;
|
|
import java.util.Vector;
|
|
import java.util.Enumeration;
|
|
import java.io.ObjectInputStream;
|
|
import java.io.ObjectOutputStream;
|
|
import java.io.IOException;
|
|
import java.io.Serializable;
|
|
|
|
/**
|
|
** PropertyChangeSupport makes it easy to fire property
|
|
** change events and handle listeners.
|
|
**
|
|
** @author John Keiser
|
|
** @since JDK1.1
|
|
** @version 1.2.0, 15 Mar 1999
|
|
**/
|
|
|
|
public class PropertyChangeSupport implements java.io.Serializable {
|
|
transient Hashtable propertyListeners = new Hashtable();
|
|
transient Vector listeners = new Vector();
|
|
Hashtable children;
|
|
Object source;
|
|
int propertyChangeSupportSerializedDataVersion = 2;
|
|
private static final long serialVersionUID = 6401253773779951803L;
|
|
|
|
/**
|
|
* Saves the state of the object to the stream. */
|
|
private void writeObject(ObjectOutputStream stream) throws IOException {
|
|
children = propertyListeners.isEmpty() ? null : propertyListeners;
|
|
stream.defaultWriteObject();
|
|
for (Enumeration e = listeners.elements(); e.hasMoreElements(); ) {
|
|
PropertyChangeListener l = (PropertyChangeListener)e.nextElement();
|
|
if (l instanceof Serializable)
|
|
stream.writeObject(l);
|
|
}
|
|
stream.writeObject(null);
|
|
}
|
|
|
|
/**
|
|
* Reads the object back from stream (deserialization).
|
|
*/
|
|
private void readObject(ObjectInputStream stream) throws IOException, ClassNotFoundException {
|
|
stream.defaultReadObject();
|
|
propertyListeners = (children == null) ? new Hashtable() : children;
|
|
PropertyChangeListener l;
|
|
while ((l = (PropertyChangeListener)stream.readObject()) != null) {
|
|
addPropertyChangeListener(l);
|
|
}
|
|
// FIXME: XXX: There is no spec for JDK 1.1 serialization
|
|
// so it is unclear what to do if the value of
|
|
// propertyChangeSupportSerializedDataVersion is 1.
|
|
}
|
|
|
|
/** Create PropertyChangeSupport to work with a specific
|
|
** source bean.
|
|
** @param source the source bean to use.
|
|
**/
|
|
public PropertyChangeSupport(Object source) {
|
|
this.source = source;
|
|
}
|
|
|
|
/** Adds a PropertyChangeListener to the list of listeners.
|
|
** All property change events will be sent to this listener.
|
|
** <P>
|
|
**
|
|
** 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 property change.
|
|
** <P>
|
|
**
|
|
** Adding a null listener will cause undefined behavior.
|
|
**
|
|
** @param l the listener to add.
|
|
**/
|
|
public void addPropertyChangeListener(PropertyChangeListener l) {
|
|
listeners.addElement(l);
|
|
}
|
|
|
|
/** Adds a PropertyChangeListener listening on the specified property.
|
|
** Events will be sent to the listener for that particular property.
|
|
** <P>
|
|
**
|
|
** 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.
|
|
** <P>
|
|
**
|
|
** The effect is cumulative, too; if you are registered to listen
|
|
** to receive events on all property changes, and then you
|
|
** register on a particular property, you will receive change
|
|
** events for that property twice.
|
|
** <P>
|
|
**
|
|
** Adding a null listener will cause undefined behavior.
|
|
**
|
|
** @param propertyName the name of the property to listen on.
|
|
** @param l the listener to add.
|
|
**/
|
|
public void addPropertyChangeListener(String propertyName, PropertyChangeListener l) {
|
|
synchronized(propertyListeners) {
|
|
Vector v = (Vector)propertyListeners.get(propertyName);
|
|
try {
|
|
v.addElement(l);
|
|
} catch(NullPointerException e) {
|
|
/* If v is not found, create a new vector. */
|
|
v = new Vector();
|
|
v.addElement(l);
|
|
propertyListeners.put(propertyName, v);
|
|
}
|
|
}
|
|
}
|
|
|
|
/** Removes a PropertyChangeListener from the list of 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.
|
|
** <P>
|
|
**
|
|
** 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.
|
|
**
|
|
** @param l the listener to remove.
|
|
**/
|
|
public void removePropertyChangeListener(PropertyChangeListener l) {
|
|
listeners.removeElement(l);
|
|
}
|
|
|
|
/** Removes a PropertyChangeListener from listening to a specific property.
|
|
** <P>
|
|
**
|
|
** 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.
|
|
**
|
|
** @param propertyName the property to stop listening on.
|
|
** @param l the listener to remove.
|
|
**/
|
|
public void removePropertyChangeListener(String propertyName, PropertyChangeListener l) {
|
|
synchronized(propertyListeners) {
|
|
Vector v = (Vector)propertyListeners.get(propertyName);
|
|
try {
|
|
v.removeElement(l);
|
|
if(v.size() == 0) {
|
|
propertyListeners.remove(propertyName);
|
|
}
|
|
} catch(NullPointerException e) {
|
|
/* if v is not found, do nothing. */
|
|
}
|
|
}
|
|
}
|
|
|
|
/** Fire a PropertyChangeEvent to all the listeners.
|
|
**
|
|
** @param event the event to fire.
|
|
**/
|
|
public void firePropertyChange(PropertyChangeEvent event) {
|
|
for(int i=0;i<listeners.size();i++) {
|
|
((PropertyChangeListener)listeners.elementAt(i)).propertyChange(event);
|
|
}
|
|
Vector moreListeners = (Vector)propertyListeners.get(event.getPropertyName());
|
|
if(moreListeners != null) {
|
|
for(int i=0;i<moreListeners.size();i++) {
|
|
((PropertyChangeListener)moreListeners.elementAt(i)).propertyChange(event);
|
|
}
|
|
}
|
|
}
|
|
|
|
/** Fire a PropertyChangeEvent containing the old and new values of the property to all the listeners.
|
|
**
|
|
** @param propertyName the name of the property that changed.
|
|
** @param oldVal the old value.
|
|
** @param newVal the new value.
|
|
**/
|
|
public void firePropertyChange(String propertyName, Object oldVal, Object newVal) {
|
|
firePropertyChange(new PropertyChangeEvent(source,propertyName,oldVal,newVal));
|
|
}
|
|
|
|
/** Fire a PropertyChangeEvent containing the old and new values of the property to all the listeners.
|
|
**
|
|
** @param propertyName the name of the property that changed.
|
|
** @param oldVal the old value.
|
|
** @param newVal the new value.
|
|
**/
|
|
public void firePropertyChange(String propertyName, boolean oldVal, boolean newVal) {
|
|
firePropertyChange(new PropertyChangeEvent(source, propertyName, new Boolean(oldVal), new Boolean(newVal)));
|
|
}
|
|
|
|
/** Fire a PropertyChangeEvent containing the old and new values of the property to all the listeners.
|
|
**
|
|
** @param propertyName the name of the property that changed.
|
|
** @param oldVal the old value.
|
|
** @param newVal the new value.
|
|
**/
|
|
public void firePropertyChange(String propertyName, int oldVal, int newVal) {
|
|
firePropertyChange(new PropertyChangeEvent(source, propertyName, new Integer(oldVal), new Integer(newVal)));
|
|
}
|
|
|
|
/** 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
|
|
**/
|
|
public boolean hasListeners(String propertyName) {
|
|
return listeners.size() > 0 || propertyListeners.get(propertyName) != null;
|
|
}
|
|
}
|