core/src/main/java/org/jclouds/xml/internal/JAXBParser.java

/**
 * Licensed to jclouds, Inc. (jclouds) under one or more
 * contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  jclouds licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package org.jclouds.xml.internal;

import java.io.IOException;
import java.io.StringReader;
import java.io.StringWriter;

import javax.inject.Singleton;
import javax.xml.bind.JAXBContext;
import javax.xml.bind.JAXBException;
import javax.xml.bind.Marshaller;
import javax.xml.bind.Unmarshaller;

import org.jclouds.http.functions.ParseXMLWithJAXB;
import org.jclouds.xml.XMLParser;

/**
 * Parses XML documents using JAXB.
 * 
 * @author Ignasi Barrera
 * @see ParseXMLWithJAXB
 */
@Singleton
public class JAXBParser implements XMLParser {
   @Override
   public String toXML(final Object src) throws IOException {
      return toXML(src, src.getClass());
   }

   @Override
   public <T> String toXML(final Object src, final Class<T> type) throws IOException {
      try {
         JAXBContext context = JAXBContext.newInstance(type);
         Marshaller marshaller = context.createMarshaller();
         StringWriter writer = new StringWriter();
         marshaller.marshal(src, writer);
         return writer.toString();
      } catch (JAXBException ex) {
         throw new IOException("Could not marshall object", ex);
      }
   }

   @SuppressWarnings("unchecked")
   @Override
   public <T> T fromXML(final String xml, final Class<T> type) throws IOException {
      try {
         StringReader reader = new StringReader(xml);
         JAXBContext context = JAXBContext.newInstance(type);
         Unmarshaller unmarshaller = context.createUnmarshaller();
         return (T) unmarshaller.unmarshal(reader);
      } catch (Exception ex) {
         throw new IOException("Could not unmarshall document", ex);
      }
   }
}