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.annotations;
016    
017    import java.lang.reflect.Method;
018    
019    import org.apache.hivemind.Location;
020    import org.apache.tapestry.enhance.EnhancementOperation;
021    import org.apache.tapestry.spec.IComponentSpecification;
022    import org.apache.tapestry.spec.IPropertySpecification;
023    import org.apache.tapestry.spec.PropertySpecification;
024    
025    /**
026     * Allow a property to be marked as persistent, and (optionally) allows a strategy to be set. Works
027     * by adding a new {@link org.apache.tapestry.spec.IPropertySpecification} to the
028     * {@link org.apache.tapestry.spec.IComponentSpecification}.
029     * <p>
030     * The {@link org.apache.tapestry.annotations.Persist} annotation may <em>optionally</em> by
031     * accompanied by a {@link org.apache.tapestry.annotations.InitialValue} annotation; this sets the
032     * initial value, as a binding reference, used to initialize and re-initialize the property.
033     * 
034     * @author Howard M. Lewis Ship
035     * @since 4.0
036     * @see org.apache.tapestry.annotations.Persist
037     */
038    public class PersistAnnotationWorker implements MethodAnnotationEnhancementWorker
039    {
040        public void performEnhancement(EnhancementOperation op, IComponentSpecification spec,
041                Method method, Location location)
042        {
043            Persist p = method.getAnnotation(Persist.class);
044            InitialValue iv = method.getAnnotation(InitialValue.class);
045    
046            String propertyName = AnnotationUtils.getPropertyName(method);
047            String stategy = p.value();
048    
049            IPropertySpecification pspec = new PropertySpecification();
050    
051            pspec.setName(propertyName);
052            pspec.setPersistence(stategy);
053            pspec.setLocation(location);
054            pspec.setInitialValue(iv == null ? null : iv.value());
055    
056            spec.addPropertySpecification(pspec);
057        }
058    
059    }