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    import org.apache.hivemind.ApplicationRuntimeException;
018    import org.apache.hivemind.impl.BaseLocatable;
019    
020    /**
021     * Simple state object factory that instantiates an instance of a class.
022     * 
023     * @author Howard M. Lewis Ship
024     * @since 4.0
025     */
026    public class InstantiateClassStateObjectFactory extends BaseLocatable implements
027            StateObjectFactory
028    {
029    
030        private Class _objectClass;
031    
032        public Object createStateObject()
033        {
034            try
035            {
036                return _objectClass.newInstance();
037            }
038            catch (Exception ex)
039            {
040                throw new ApplicationRuntimeException(StateMessages
041                        .unableToInstantiateObject(_objectClass, ex),
042                        getLocation(), ex);
043            }
044        }
045    
046        public void setObjectClass(Class objectClass)
047        {
048            _objectClass = objectClass;
049        }
050    }