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
015package org.apache.tapestry.engine.state;
016
017import org.apache.hivemind.util.Defense;
018
019/**
020 * @author Howard M. Lewis Ship
021 * @since 4.0
022 */
023public class StateObjectManagerImpl implements StateObjectManager
024{
025    private StateObjectPersistenceManager _persistenceManager;
026
027    private StateObjectFactory _factory;
028
029    private String _name;
030
031    public StateObjectManagerImpl(String name, StateObjectFactory factory,
032            StateObjectPersistenceManager persistenceManager)
033    {
034        Defense.notNull(name, "name");
035        Defense.notNull(factory, "factory");
036        Defense.notNull(persistenceManager, "persistenceManager");
037
038        _name = name;
039        _factory = factory;
040        _persistenceManager = persistenceManager;
041    }
042
043    public boolean exists()
044    {
045        return _persistenceManager.exists(_name);
046    }
047
048    public Object get()
049    {
050        return _persistenceManager.get(_name, _factory);
051    }
052
053    public void store(Object stateObject)
054    {
055        _persistenceManager.store(_name, stateObject);
056    }
057}