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.camel.component.bean;
018
019 import java.lang.annotation.Annotation;
020
021 import org.apache.camel.CamelContext;
022 import org.apache.camel.Expression;
023 import org.apache.camel.builder.xml.XPathBuilder;
024 import org.apache.camel.language.LanguageAnnotation;
025 import org.apache.camel.language.NamespacePrefix;
026 import org.apache.camel.util.ObjectHelper;
027
028 /**
029 * Factory for the XPath expression annotations.
030 *
031 * @version
032 */
033 public class XPathAnnotationExpressionFactory extends DefaultAnnotationExpressionFactory {
034
035 @Override
036 public Expression createExpression(CamelContext camelContext, Annotation annotation, LanguageAnnotation languageAnnotation, Class<?> expressionReturnType) {
037 String xpath = getExpressionFromAnnotation(annotation);
038
039 Class<?> resultType = getResultType(annotation);
040 if (resultType.equals(Object.class)) {
041 resultType = expressionReturnType;
042 }
043
044 XPathBuilder builder = XPathBuilder.xpath(xpath, resultType);
045 NamespacePrefix[] namespaces = getExpressionNameSpacePrefix(annotation);
046 if (namespaces != null) {
047 for (NamespacePrefix namespacePrefix : namespaces) {
048 builder = builder.namespace(namespacePrefix.prefix(), namespacePrefix.uri());
049 }
050 }
051
052 // Set the header name that we want the XPathBuilder to apply the XPath expression to
053 String headerName = getHeaderName(annotation);
054 if (ObjectHelper.isNotEmpty(headerName)) {
055 builder.setHeaderName(headerName);
056 }
057
058 return builder;
059 }
060
061 protected Class<?> getResultType(Annotation annotation) {
062 return (Class<?>) getAnnotationObjectValue(annotation, "resultType");
063 }
064
065 protected NamespacePrefix[] getExpressionNameSpacePrefix(Annotation annotation) {
066 return (NamespacePrefix[]) getAnnotationObjectValue(annotation, "namespaces");
067 }
068
069 /**
070 * Extracts the value of the header method in the Annotation. For backwards
071 * compatibility this method will return null if the annotation's method is
072 * not found.
073 *
074 * @return If the annotation has the method 'header' then the name of the
075 * header we want to apply the XPath expression to. Otherwise null
076 * will be returned
077 */
078 protected String getHeaderName(Annotation annotation) {
079 String headerValue = null;
080 try {
081 headerValue = (String)getAnnotationObjectValue(annotation, "headerName");
082 } catch (Exception e) {
083 // Do Nothing
084 }
085 return headerValue;
086 }
087 }