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.contrib.inspector;
016    
017    import java.util.ArrayList;
018    import java.util.Collection;
019    import java.util.List;
020    
021    import org.apache.hivemind.service.ClassFabUtils;
022    import org.apache.tapestry.BaseComponent;
023    import org.apache.tapestry.IPage;
024    import org.apache.tapestry.event.PageBeginRenderListener;
025    import org.apache.tapestry.event.PageEvent;
026    import org.apache.tapestry.record.PropertyChange;
027    import org.apache.tapestry.record.PropertyPersistenceStrategySource;
028    
029    /**
030     * Component of the {@link Inspector}page used to display the persisent properties of the page.
031     * 
032     * @author Howard Lewis Ship
033     */
034    
035    public abstract class ShowProperties extends BaseComponent implements PageBeginRenderListener
036    {
037    
038        public abstract void setProperties(List properties);
039    
040        public abstract PropertyChange getChange();
041    
042        /** Injected. */
043    
044        public abstract PropertyPersistenceStrategySource getPropertySource();
045    
046        public void pageBeginRender(PageEvent event)
047        {
048            Inspector inspector = (Inspector) getPage();
049    
050            IPage inspectedPage = inspector.getInspectedPage();
051    
052            String pageName = inspectedPage.getPageName();
053    
054            PropertyPersistenceStrategySource source = getPropertySource();
055    
056            Collection properties = source.getAllStoredChanges(pageName);
057    
058            // TODO: sorting
059    
060            setProperties(new ArrayList(properties));
061        }
062    
063        /**
064         * Returns the name of the value's class, if the value is non-null.
065         */
066    
067        public String getValueClassName()
068        {
069            Object value = getChange().getNewValue();
070    
071            if (value == null)
072                return "<null>";
073    
074            return ClassFabUtils.getJavaClassName(value.getClass());
075        }
076    }