001    // Copyright 2004, 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    package org.apache.tapestry.enhance;
015    
016    import java.beans.BeanInfo;
017    import java.beans.Introspector;
018    import java.beans.PropertyDescriptor;
019    import java.lang.reflect.Method;
020    
021    import org.apache.hivemind.ApplicationRuntimeException;
022    
023    
024    /**
025     * Implemenation of {@link ClassInspector} that is compatible with 
026     * 1.4 jres.
027     */
028    public class ClassInspectorImpl implements ClassInspector
029    {
030    
031        /**
032         * {@inheritDoc}
033         */
034        public MethodSignature getMethodSignature(Class implementing, Method m)
035        {
036            return new MethodSignatureImpl(m);
037        }
038        
039        /**
040         * {@inheritDoc}
041         */
042        public MethodSignature getPropertyAccessor(Class type, String propertyName)
043        {
044            try {
045                BeanInfo info = Introspector.getBeanInfo(type);
046                PropertyDescriptor[] props = info.getPropertyDescriptors();
047                
048                for (int i=0; i < props.length; i++) {
049                    
050                    if (!propertyName.equals(props[i].getName())) {
051                        continue;
052                    }
053                    
054                    return new MethodSignatureImpl(props[i].getReadMethod() != null ? props[i].getReadMethod() : props[i].getWriteMethod());
055                } 
056                
057            } catch (Throwable t) {
058                
059                throw new ApplicationRuntimeException("Error reading property " + propertyName + " from base class : " + type, t);
060            }
061            
062            return null;
063        }
064    
065    }