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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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 * accompanied this code).
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 * 2 along with this work; if not, write to the Free Software Foundation,
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package java.util.prefs;

import java.io.NotSerializableException;

An event emitted by a Preferences node to indicate that a preference has been added, removed or has had its value changed.

Note, that although PreferenceChangeEvent inherits Serializable interface
from EventObject, it is not intended to be Serializable. Appropriate
serialization methods are implemented to throw NotSerializableException.
Author:
 Josh Bloch
See Also:
Preferences
PreferenceChangeListener
NodeChangeEvent
Since:
  1.4
@serial
exclude/**
 * An event emitted by a {@code Preferences} node to indicate that
 * a preference has been added, removed or has had its value changed.<p>
 *
 * Note, that although PreferenceChangeEvent inherits Serializable interface
 * from EventObject, it is not intended to be Serializable. Appropriate
 * serialization methods are implemented to throw NotSerializableException.
 *
 * @author  Josh Bloch
 * @see Preferences
 * @see PreferenceChangeListener
 * @see NodeChangeEvent
 * @since   1.4
 * @serial exclude
 */
public class PreferenceChangeEvent extends java.util.EventObject {

    
Key of the preference that changed.
@serial
/**
     * Key of the preference that changed.
     *
     * @serial
     */
    private String key;

    
New value for preference, or null if it was removed. 
@serial
/**
     * New value for preference, or {@code null} if it was removed.
     *
     * @serial
     */
    private String newValue;

    
Constructs a new PreferenceChangeEvent instance. 
Params:
node –  The Preferences node that emitted the event.
key –  The key of the preference that was changed.
newValue –  The new value of the preference, or null if the preference is being removed./**
     * Constructs a new {@code PreferenceChangeEvent} instance.
     *
     * @param node  The Preferences node that emitted the event.
     * @param key  The key of the preference that was changed.
     * @param newValue  The new value of the preference, or {@code null}
     *                  if the preference is being removed.
     */
    public PreferenceChangeEvent(Preferences node, String key,
                                 String newValue) {
        super(node);
        this.key = key;
        this.newValue = newValue;
    }

    
Returns the preference node that emitted the event.
Returns:
 The preference node that emitted the event./**
     * Returns the preference node that emitted the event.
     *
     * @return  The preference node that emitted the event.
     */
    public Preferences getNode() {
        return (Preferences) getSource();
    }

    
Returns the key of the preference that was changed.
Returns:
 The key of the preference that was changed./**
     * Returns the key of the preference that was changed.
     *
     * @return  The key of the preference that was changed.
     */
    public String getKey() {
        return key;
    }

    
Returns the new value for the preference.
Returns:
 The new value for the preference, or null if the preference was removed./**
     * Returns the new value for the preference.
     *
     * @return  The new value for the preference, or {@code null} if the
     *          preference was removed.
     */
    public String getNewValue() {
        return newValue;
    }

    
Throws NotSerializableException, since NodeChangeEvent objects
are not intended to be serializable.
/**
     * Throws NotSerializableException, since NodeChangeEvent objects
     * are not intended to be serializable.
     */
     private void writeObject(java.io.ObjectOutputStream out)
                                               throws NotSerializableException {
         throw new NotSerializableException("Not serializable.");
     }

    
Throws NotSerializableException, since PreferenceChangeEvent objects
are not intended to be serializable.
/**
     * Throws NotSerializableException, since PreferenceChangeEvent objects
     * are not intended to be serializable.
     */
     private void readObject(java.io.ObjectInputStream in)
                                               throws NotSerializableException {
         throw new NotSerializableException("Not serializable.");
     }

    // Defined so that this class isn't flagged as a potential problem when
    // searches for missing serialVersionUID fields are done.
    private static final long serialVersionUID = 793724513368024975L;
}