/**
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF 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.apache.camel.converter.jaxb;
import java.io.Closeable;
import java.io.InputStream;
import java.io.Reader;
import java.io.StringReader;
import java.io.StringWriter;
import java.util.HashMap;
import java.util.Map;
import javax.xml.bind.JAXBContext;
import javax.xml.bind.JAXBException;
import javax.xml.bind.Marshaller;
import javax.xml.bind.Unmarshaller;
import javax.xml.bind.annotation.XmlRootElement;
import javax.xml.bind.util.JAXBSource;
import javax.xml.transform.Source;
import org.apache.camel.Exchange;
import org.apache.camel.NoTypeConversionAvailableException;
import org.apache.camel.RuntimeCamelException;
import org.apache.camel.StreamCache;
import org.apache.camel.TypeConverter;
import org.apache.camel.spi.TypeConverterAware;
import org.apache.camel.util.ObjectHelper;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
/**
* @version $Revision: 755958 $
*/
public class FallbackTypeConverter implements TypeConverter, TypeConverterAware {
private static final transient Log LOG = LogFactory.getLog(FallbackTypeConverter.class);
private Map<Class, JAXBContext> contexts = new HashMap<Class, JAXBContext>();
private TypeConverter parentTypeConverter;
private boolean prettyPrint = true;
public boolean isPrettyPrint() {
return prettyPrint;
}
public void setPrettyPrint(boolean prettyPrint) {
this.prettyPrint = prettyPrint;
}
public void setTypeConverter(TypeConverter parentTypeConverter) {
this.parentTypeConverter = parentTypeConverter;
}
public <T> T convertTo(Class<T> type, Object value) {
try {
if (isJaxbType(type)) {
return unmarshall(type, value);
}
if (value != null) {
if (isJaxbType(value.getClass()) && isNotStreamCacheType(type)) {
return marshall(type, value);
}
}
return null;
} catch (JAXBException e) {
throw new RuntimeCamelException(e);
}
}
private <T> boolean isNotStreamCacheType(Class<T> type) {
return !StreamCache.class.isAssignableFrom(type);
}
public <T> T convertTo(Class<T> type, Exchange exchange, Object value) {
return convertTo(type, value);
}
public <T> T mandatoryConvertTo(Class<T> type, Object value) throws NoTypeConversionAvailableException {
T answer = convertTo(type, value);
if (answer == null) {
throw new NoTypeConversionAvailableException(value, type);
}
return answer;
}
public <T> T mandatoryConvertTo(Class<T> type, Exchange exchange, Object value) throws NoTypeConversionAvailableException {
return mandatoryConvertTo(type, value);
}
protected <T> boolean isJaxbType(Class<T> type) {
XmlRootElement element = type.getAnnotation(XmlRootElement.class);
return element != null;
}
/**
* Lets try parse via JAXB
*/
protected <T> T unmarshall(Class<T> type, Object value) throws JAXBException {
if (value == null) {
throw new IllegalArgumentException("Cannot convert from null value to JAXBSource");
}
JAXBContext context = createContext(type);
// must create a new instance of unmarshaller as its not thred safe
Unmarshaller unmarshaller = context.createUnmarshaller();
if (parentTypeConverter != null) {
InputStream inputStream = parentTypeConverter.convertTo(InputStream.class, value);
if (inputStream != null) {
Object unmarshalled = unmarshal(unmarshaller, inputStream);
return type.cast(unmarshalled);
}
Reader reader = parentTypeConverter.convertTo(Reader.class, value);
if (reader != null) {
Object unmarshalled = unmarshal(unmarshaller, reader);
return type.cast(unmarshalled);
}
Source source = parentTypeConverter.convertTo(Source.class, value);
if (source != null) {
Object unmarshalled = unmarshal(unmarshaller, source);
return type.cast(unmarshalled);
}
}
if (value instanceof String) {
value = new StringReader((String) value);
}
if (value instanceof InputStream || value instanceof Reader) {
Object unmarshalled = unmarshal(unmarshaller, value);
return type.cast(unmarshalled);
}
return null;
}
protected <T> T marshall(Class<T> type, Object value) throws JAXBException {
T answer = null;
if (parentTypeConverter != null) {
// lets convert the object to a JAXB source and try convert that to
// the required source
JAXBContext context = createContext(value.getClass());
JAXBSource source = new JAXBSource(context, value);
answer = parentTypeConverter.convertTo(type, source);
if (answer == null) {
// lets try a stream
StringWriter buffer = new StringWriter();
// must create a new instance of marshaller as its not thred safe
Marshaller marshaller = context.createMarshaller();
marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, isPrettyPrint() ? Boolean.TRUE : Boolean.FALSE);
marshaller.marshal(value, buffer);
answer = parentTypeConverter.convertTo(type, buffer.toString());
}
}
return answer;
}
/**
* Unmarshals the given value with the unmarshaller
*
* @param unmarshaller the unmarshaller
* @param value the stream to unmarshal (will close it after use, also if exception is thrown)
* @return the value
* @throws JAXBException is thrown if an exception occur while unmarshalling
*/
protected Object unmarshal(Unmarshaller unmarshaller, Object value) throws JAXBException {
try {
if (value instanceof InputStream) {
return unmarshaller.unmarshal((InputStream) value);
} else if (value instanceof Reader) {
return unmarshaller.unmarshal((Reader) value);
} else if (value instanceof Source) {
return unmarshaller.unmarshal((Source) value);
}
} finally {
if (value instanceof Closeable) {
ObjectHelper.close((Closeable) value, "Unmarshalling", LOG);
}
}
return null;
}
protected synchronized <T> JAXBContext createContext(Class<T> type) throws JAXBException {
JAXBContext context = contexts.get(type);
if (context == null) {
context = JAXBContext.newInstance(type);
contexts.put(type, context);
}
return context;
}
}