001    /**
002     * Licensed to the Apache Software Foundation (ASF) under one or more
003     * contributor license agreements.  See the NOTICE file distributed with
004     * this work for additional information regarding copyright ownership.
005     * The ASF licenses this file to You under the Apache License, Version 2.0
006     * (the "License"); you may not use this file except in compliance with
007     * the License.  You may obtain a copy of the License at
008     *
009     *      http://www.apache.org/licenses/LICENSE-2.0
010     *
011     * Unless required by applicable law or agreed to in writing, software
012     * distributed under the License is distributed on an "AS IS" BASIS,
013     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014     * See the License for the specific language governing permissions and
015     * limitations under the License.
016     */
017    package org.apache.xbean.spring.context.impl;
018    
019    import org.springframework.beans.factory.BeanDefinitionStoreException;
020    import org.springframework.beans.factory.support.AbstractBeanDefinition;
021    import org.w3c.dom.Element;
022    
023    import java.beans.PropertyDescriptor;
024    import java.lang.reflect.Method;
025    
026    /**
027     * To avoid a runtime dependency on the QName class lets use reflection to
028     * process QName instances.
029     * 
030     * @version $Revision: 1.1 $
031     */
032    public class QNameReflectionHelper {
033    
034        protected static Method coerceMethod;
035        protected static Method createMethod;
036    
037        public static void coerceNamespaceAwarePropertyValues(AbstractBeanDefinition beanDefinition, Element element,
038                PropertyDescriptor[] descriptors, int index) {
039            QNameReflectionParams params = new QNameReflectionParams(beanDefinition, element, descriptors, index);
040            if (coerceMethod == null) {
041                coerceMethod = findMethod("coerceQNamePropertyValues");
042            }
043            if (coerceMethod != null) {
044                try {
045                    coerceMethod.invoke(null, new Object[] { params });
046                }
047                catch (Exception e) {
048                    throw new BeanDefinitionStoreException("Failed to invoke method: " + coerceMethod + " via reflection: " + e,
049                            e);
050                }
051            }
052        }
053        
054        public static Object createQName(Element element, String text) {
055            if (createMethod == null) {
056                createMethod = findMethod("createQName");
057            }
058            if (createMethod != null) {
059                try {
060                    return createMethod.invoke(null, new Object[] { element, text });
061                }
062                catch (Exception e) {
063                    throw new BeanDefinitionStoreException("Failed to invoke method: " + createMethod + " via reflection: " + e,
064                            e);
065                }
066            }
067            return null;
068        }
069    
070        protected static Method findMethod(String name) {
071            try {
072                Class type = PropertyEditorHelper.loadClass("org.apache.xbean.spring.context.impl.QNameHelper");
073                if (type != null) {
074                    Method[] methods = type.getMethods();
075                    for (int i = 0; i < methods.length; i++) {
076                        Method method = methods[i];
077                        if (method.getName().equals(name)) {
078                            return method;
079                        }
080                    }
081                }
082            } catch (Throwable t) {
083                // Ignore, this is usually because QName method is not in the classpath 
084            }
085            return null;
086        }
087    
088    }