001    // Copyright 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.state;
016    
017    /**
018     * Interface for the nuts and bolts of getting and storing application state
019     * objects. These are intended to be stateless, and manage a number of state
020     * objects, mapping objectNames to internal storage in some way.
021     * 
022     * @author Howard M. Lewis Ship
023     * @since 4.0
024     */
025    public interface StateObjectPersistenceManager
026    {
027    
028        boolean exists(String objectName);
029    
030        Object get(String objectName, StateObjectFactory factory);
031    
032        void store(String objectName, Object stateObject);
033    }