001    /*
002     * Copyright 2005 Stephen J. McConnell.
003     *
004     * Licensed  under the  Apache License,  Version 2.0  (the "License");
005     * you may not use  this file  except in  compliance with the License.
006     * You may obtain a copy of the License at
007     *
008     *   http://www.apache.org/licenses/LICENSE-2.0
009     *
010     * Unless required by applicable law or agreed to in writing, software
011     * distributed  under the  License is distributed on an "AS IS" BASIS,
012     * WITHOUT  WARRANTIES OR CONDITIONS  OF ANY KIND, either  express  or
013     * implied.
014     *
015     * See the License for the specific language governing permissions and
016     * limitations under the License.
017     */
018    
019    package net.dpml.station;
020    
021    import java.beans.Expression;
022    import java.beans.BeanDescriptor;
023    import java.beans.DefaultPersistenceDelegate;
024    import java.beans.SimpleBeanInfo;
025    import java.beans.Encoder;
026    
027    /**
028     * Bean info for state encoding of the ProcessState enumeration.
029     * @author <a href="http://www.dpml.net">Digital Product Meta Library</a>
030     * @version 1.0.1
031     */
032    public final class ProcessStateBeanInfo extends SimpleBeanInfo
033    {
034        private static final BeanDescriptor BEAN_DESCRIPTOR = setupBeanDescriptor();
035    
036       /**
037        * Creation of a bean descriptor.
038        * @return the bean descriptor
039        */
040        public BeanDescriptor getBeanDescriptor()
041        {
042            return BEAN_DESCRIPTOR;
043        }
044        
045        private static BeanDescriptor setupBeanDescriptor()
046        {
047            BeanDescriptor descriptor = new BeanDescriptor( ProcessState.class );
048            descriptor.setValue( 
049              "persistenceDelegate", 
050              new ScopePersistenceDelegate() );
051            return descriptor;
052        }
053        
054       /**
055        * Scope persitence delegate.
056        */
057        private static class ScopePersistenceDelegate extends DefaultPersistenceDelegate
058        {
059           /**
060            * Return an expression.
061            * @param old the old value
062            * @param encoder the encoder
063            * @return an expression
064            */
065            public Expression instantiate( Object old, Encoder encoder )
066            {
067                ProcessState state = (ProcessState) old;
068                return new Expression( state, ProcessState.class, "parse", new Object[]{state.getName()} );
069            }
070        }
071    }