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.ApplicationRuntimeException;
020    import org.apache.hivemind.ClassResolver;
021    import org.apache.hivemind.Location;
022    import org.apache.hivemind.Resource;
023    import org.apache.hivemind.util.ClasspathResource;
024    import org.apache.tapestry.enhance.EnhancementOperation;
025    import org.apache.tapestry.enhance.EnhancementWorker;
026    import org.apache.tapestry.enhance.InjectAssetWorker;
027    import org.apache.tapestry.spec.IAssetSpecification;
028    import org.apache.tapestry.spec.IComponentSpecification;
029    
030    /**
031     * Injects an asset.
032     * 
033     * @author Howard M. Lewis Ship
034     * @since 4.0
035     * @see org.apache.tapestry.annotations.InjectAsset
036     * @see org.apache.tapestry.enhance.InjectAssetWorker
037     */
038    public class InjectAssetAnnotationWorker implements EnhancementWorker
039    {
040        InjectAssetWorker _delegate;
041        
042        private ClassResolver _classResolver;
043        
044        InjectAssetAnnotationWorker(InjectAssetWorker delegate)
045        {
046            _delegate = delegate;
047        }
048    
049        public InjectAssetAnnotationWorker()
050        {
051            this(new InjectAssetWorker());
052        }
053        
054        public void performEnhancement(EnhancementOperation op, IComponentSpecification spec)
055        {
056            Class clazz = op.getBaseClass();
057            
058            Resource classResource = newClassResource(clazz);
059            
060            for (Method m : clazz.getMethods())
061            {
062                if (m.getAnnotation(InjectAsset.class) != null) {
063                    
064                    performEnhancement(op, spec, m, 
065                            AnnotationUtils.buildLocationForAnnotation(
066                            m,
067                            m.getAnnotation(InjectAsset.class),
068                            classResource));
069                }
070            }
071        }
072        
073        private ClasspathResource newClassResource(Class clazz)
074        {
075            return new ClasspathResource(_classResolver, clazz.getName().replace('.', '/'));
076        }
077        
078        public void performEnhancement(EnhancementOperation op, IComponentSpecification spec, Method method, Location location)
079        {
080            InjectAsset as = method.getAnnotation(InjectAsset.class);
081            
082            IAssetSpecification asset = spec.getAsset(as.value());
083            if (asset == null) {
084                
085                throw new ApplicationRuntimeException(AnnotationMessages.unknownAsset(as.value(), location));
086            }
087            
088            String propertyName = AnnotationUtils.getPropertyName(method);
089            
090            _delegate.injectAsset(op, as.value(), propertyName, location);
091        }
092    
093        public void setClassResolver(ClassResolver classResolver)
094        {
095            _classResolver = classResolver;
096        }
097    }