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.model;
018
019 import java.io.InputStream;
020 import java.io.StringReader;
021 import java.io.StringWriter;
022 import javax.xml.bind.JAXBContext;
023 import javax.xml.bind.JAXBException;
024 import javax.xml.bind.Marshaller;
025 import javax.xml.bind.Unmarshaller;
026
027 import org.apache.camel.CamelContext;
028 import org.apache.camel.NamedNode;
029
030 /**
031 * Helper for the Camel {@link org.apache.camel.model model} classes.
032 */
033 public final class ModelHelper {
034
035 private ModelHelper() {
036 // utility class
037 }
038
039 /**
040 * Dumps the definition as XML
041 *
042 * @param definition the definition, such as a {@link org.apache.camel.NamedNode}
043 * @return the output in XML (is formatted)
044 * @throws JAXBException is throw if error marshalling to XML
045 */
046 public static String dumpModelAsXml(NamedNode definition) throws JAXBException {
047 JAXBContext jaxbContext = createJaxbContext();
048
049 Marshaller marshaller = jaxbContext.createMarshaller();
050 marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, Boolean.TRUE);
051 StringWriter buffer = new StringWriter();
052 marshaller.marshal(definition, buffer);
053
054 return buffer.toString();
055 }
056
057 /**
058 * Marshal the xml to the model definition
059 *
060 * @param xml the xml
061 * @param type the definition type to return, will throw a {@link ClassCastException} if not the expected type
062 * @return the model definition
063 * @throws javax.xml.bind.JAXBException is thrown if error unmarshalling from xml to model
064 */
065 public static <T extends NamedNode> T createModelFromXml(String xml, Class<T> type) throws JAXBException {
066 JAXBContext jaxbContext = createJaxbContext();
067 StringReader reader = new StringReader(xml);
068 Unmarshaller unmarshaller = jaxbContext.createUnmarshaller();
069 Object result = unmarshaller.unmarshal(reader);
070 reader.close();
071
072 if (result == null) {
073 throw new JAXBException("Cannot unmarshal to " + type + " using JAXB from XML: " + xml);
074 }
075 return type.cast(result);
076 }
077
078 /**
079 * Marshal the xml to the model definition
080 *
081 * @param stream the xml stream
082 * @param type the definition type to return, will throw a {@link ClassCastException} if not the expected type
083 * @return the model definition
084 * @throws javax.xml.bind.JAXBException is thrown if error unmarshalling from xml to model
085 */
086 public static <T extends NamedNode> T createModelFromXml(InputStream stream, Class<T> type) throws JAXBException {
087 JAXBContext jaxbContext = createJaxbContext();
088 Unmarshaller unmarshaller = jaxbContext.createUnmarshaller();
089 Object result = unmarshaller.unmarshal(stream);
090 return type.cast(result);
091 }
092
093 public static JAXBContext createJaxbContext() throws JAXBException {
094 // must use classloader from CamelContext to have JAXB working
095 return JAXBContext.newInstance(Constants.JAXB_CONTEXT_PACKAGES, CamelContext.class.getClassLoader());
096 }
097 }