jaroslav@601: /*
jaroslav@601:  * Copyright (c) 1996, 2010, Oracle and/or its affiliates. All rights reserved.
jaroslav@601:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
jaroslav@601:  *
jaroslav@601:  * This code is free software; you can redistribute it and/or modify it
jaroslav@601:  * under the terms of the GNU General Public License version 2 only, as
jaroslav@601:  * published by the Free Software Foundation.  Oracle designates this
jaroslav@601:  * particular file as subject to the "Classpath" exception as provided
jaroslav@601:  * by Oracle in the LICENSE file that accompanied this code.
jaroslav@601:  *
jaroslav@601:  * This code is distributed in the hope that it will be useful, but WITHOUT
jaroslav@601:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
jaroslav@601:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
jaroslav@601:  * version 2 for more details (a copy is included in the LICENSE file that
jaroslav@601:  * accompanied this code).
jaroslav@601:  *
jaroslav@601:  * You should have received a copy of the GNU General Public License version
jaroslav@601:  * 2 along with this work; if not, write to the Free Software Foundation,
jaroslav@601:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
jaroslav@601:  *
jaroslav@601:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
jaroslav@601:  * or visit www.oracle.com if you need additional information or have any
jaroslav@601:  * questions.
jaroslav@601:  */
jaroslav@601: 
jaroslav@601: package java.beans;
jaroslav@601: 
jaroslav@601: /**
jaroslav@601:  * A "PropertyChange" event gets delivered whenever a bean changes a "bound"
jaroslav@601:  * or "constrained" property.  A PropertyChangeEvent object is sent as an
jaroslav@601:  * argument to the PropertyChangeListener and VetoableChangeListener methods.
jaroslav@601:  * <P>
jaroslav@601:  * Normally PropertyChangeEvents are accompanied by the name and the old
jaroslav@601:  * and new value of the changed property.  If the new value is a primitive
jaroslav@601:  * type (such as int or boolean) it must be wrapped as the
jaroslav@601:  * corresponding java.lang.* Object type (such as Integer or Boolean).
jaroslav@601:  * <P>
jaroslav@601:  * Null values may be provided for the old and the new values if their
jaroslav@601:  * true values are not known.
jaroslav@601:  * <P>
jaroslav@601:  * An event source may send a null object as the name to indicate that an
jaroslav@601:  * arbitrary set of if its properties have changed.  In this case the
jaroslav@601:  * old and new values should also be null.
jaroslav@601:  */
jaroslav@601: 
jaroslav@601: public class PropertyChangeEvent extends java.util.EventObject {
jaroslav@601:     private static final long serialVersionUID = 7042693688939648123L;
jaroslav@601: 
jaroslav@601:     /**
jaroslav@601:      * Constructs a new <code>PropertyChangeEvent</code>.
jaroslav@601:      *
jaroslav@601:      * @param source  The bean that fired the event.
jaroslav@601:      * @param propertyName  The programmatic name of the property
jaroslav@601:      *          that was changed.
jaroslav@601:      * @param oldValue  The old value of the property.
jaroslav@601:      * @param newValue  The new value of the property.
jaroslav@601:      */
jaroslav@601:     public PropertyChangeEvent(Object source, String propertyName,
jaroslav@601:                                      Object oldValue, Object newValue) {
jaroslav@601:         super(source);
jaroslav@601:         this.propertyName = propertyName;
jaroslav@601:         this.newValue = newValue;
jaroslav@601:         this.oldValue = oldValue;
jaroslav@601:     }
jaroslav@601: 
jaroslav@601:     /**
jaroslav@601:      * Gets the programmatic name of the property that was changed.
jaroslav@601:      *
jaroslav@601:      * @return  The programmatic name of the property that was changed.
jaroslav@601:      *          May be null if multiple properties have changed.
jaroslav@601:      */
jaroslav@601:     public String getPropertyName() {
jaroslav@601:         return propertyName;
jaroslav@601:     }
jaroslav@601: 
jaroslav@601:     /**
jaroslav@601:      * Gets the new value for the property, expressed as an Object.
jaroslav@601:      *
jaroslav@601:      * @return  The new value for the property, expressed as an Object.
jaroslav@601:      *          May be null if multiple properties have changed.
jaroslav@601:      */
jaroslav@601:     public Object getNewValue() {
jaroslav@601:         return newValue;
jaroslav@601:     }
jaroslav@601: 
jaroslav@601:     /**
jaroslav@601:      * Gets the old value for the property, expressed as an Object.
jaroslav@601:      *
jaroslav@601:      * @return  The old value for the property, expressed as an Object.
jaroslav@601:      *          May be null if multiple properties have changed.
jaroslav@601:      */
jaroslav@601:     public Object getOldValue() {
jaroslav@601:         return oldValue;
jaroslav@601:     }
jaroslav@601: 
jaroslav@601:     /**
jaroslav@601:      * Sets the propagationId object for the event.
jaroslav@601:      *
jaroslav@601:      * @param propagationId  The propagationId object for the event.
jaroslav@601:      */
jaroslav@601:     public void setPropagationId(Object propagationId) {
jaroslav@601:         this.propagationId = propagationId;
jaroslav@601:     }
jaroslav@601: 
jaroslav@601:     /**
jaroslav@601:      * The "propagationId" field is reserved for future use.  In Beans 1.0
jaroslav@601:      * the sole requirement is that if a listener catches a PropertyChangeEvent
jaroslav@601:      * and then fires a PropertyChangeEvent of its own, then it should
jaroslav@601:      * make sure that it propagates the propagationId field from its
jaroslav@601:      * incoming event to its outgoing event.
jaroslav@601:      *
jaroslav@601:      * @return the propagationId object associated with a bound/constrained
jaroslav@601:      *          property update.
jaroslav@601:      */
jaroslav@601:     public Object getPropagationId() {
jaroslav@601:         return propagationId;
jaroslav@601:     }
jaroslav@601: 
jaroslav@601:     /**
jaroslav@601:      * name of the property that changed.  May be null, if not known.
jaroslav@601:      * @serial
jaroslav@601:      */
jaroslav@601:     private String propertyName;
jaroslav@601: 
jaroslav@601:     /**
jaroslav@601:      * New value for property.  May be null if not known.
jaroslav@601:      * @serial
jaroslav@601:      */
jaroslav@601:     private Object newValue;
jaroslav@601: 
jaroslav@601:     /**
jaroslav@601:      * Previous value for property.  May be null if not known.
jaroslav@601:      * @serial
jaroslav@601:      */
jaroslav@601:     private Object oldValue;
jaroslav@601: 
jaroslav@601:     /**
jaroslav@601:      * Propagation ID.  May be null.
jaroslav@601:      * @serial
jaroslav@601:      * @see #getPropagationId
jaroslav@601:      */
jaroslav@601:     private Object propagationId;
jaroslav@601: 
jaroslav@601:     /**
jaroslav@601:      * Returns a string representation of the object.
jaroslav@601:      *
jaroslav@601:      * @return a string representation of the object
jaroslav@601:      *
jaroslav@601:      * @since 1.7
jaroslav@601:      */
jaroslav@601:     public String toString() {
jaroslav@601:         StringBuilder sb = new StringBuilder(getClass().getName());
jaroslav@601:         sb.append("[propertyName=").append(getPropertyName());
jaroslav@601:         appendTo(sb);
jaroslav@601:         sb.append("; oldValue=").append(getOldValue());
jaroslav@601:         sb.append("; newValue=").append(getNewValue());
jaroslav@601:         sb.append("; propagationId=").append(getPropagationId());
jaroslav@601:         sb.append("; source=").append(getSource());
jaroslav@601:         return sb.append("]").toString();
jaroslav@601:     }
jaroslav@601: 
jaroslav@601:     void appendTo(StringBuilder sb) {
jaroslav@601:     }
jaroslav@601: }