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.engine;
016    
017    import java.util.Collection;
018    import java.util.Collections;
019    
020    /**
021     * Concrete implementation of {@link org.apache.tapestry.IEngine} used for ordinary applications.
022     * All page state information is maintained in the {@link javax.servlet.http.HttpSession}.
023     * 
024     * @author Howard Lewis Ship
025     */
026    
027    public class BaseEngine extends AbstractEngine
028    {
029        /**
030         * Returns an unmodifiable {@link Collection} of the page names for which {@link IPageRecorder}
031         * instances exist. Note: Starting in 4.0, this method is deprecated and returns an empty list.
032         * 
033         * @deprecated
034         */
035    
036        public Collection getActivePageNames()
037        {
038            return Collections.EMPTY_LIST;
039    
040        }
041    }