001    // Copyright 2004, 2005 The Apache Software Foundation
002    //
003    // Licensed under the Apache License, Version 2.0 (the "License");
004    // you may not use this file except in compliance with the License.
005    // You may obtain a copy of the License at
006    //
007    //     http://www.apache.org/licenses/LICENSE-2.0
008    //
009    // Unless required by applicable law or agreed to in writing, software
010    // distributed under the License is distributed on an "AS IS" BASIS,
011    // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
012    // See the License for the specific language governing permissions and
013    // limitations under the License.
014    
015    package org.apache.tapestry.record;
016    
017    /**
018     * Represents a change to a component on a page, this represents a datum of
019     * information stored by a {@link org.apache.tapestry.engine.IPageRecorder}.
020     * <p>
021     * Renamed from IPageChange in release 4.0.
022     * 
023     * @author Howard Lewis Ship
024     */
025    
026    public interface PropertyChange
027    {
028    
029        /**
030         * The path to the component on the page, or null if the property is a
031         * property of the page.
032         */
033    
034        String getComponentPath();
035    
036        /**
037         * The new value for the property, which may be null.
038         */
039    
040        Object getNewValue();
041    
042        /**
043         * The name of the property that changed.
044         */
045    
046        String getPropertyName();
047    }