/**
* 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.dataformat.xstream;
import java.io.InputStream;
import java.io.OutputStream;
import java.lang.reflect.Constructor;
import java.lang.reflect.Method;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import javax.xml.stream.XMLStreamException;
import com.thoughtworks.xstream.XStream;
import com.thoughtworks.xstream.converters.Converter;
import com.thoughtworks.xstream.io.HierarchicalStreamReader;
import com.thoughtworks.xstream.io.HierarchicalStreamWriter;
import org.apache.camel.Exchange;
import org.apache.camel.converter.jaxp.StaxConverter;
import org.apache.camel.spi.ClassResolver;
import org.apache.camel.spi.DataFormat;
import org.apache.camel.util.ObjectHelper;
/**
* An abstract class which implement <a href="http://camel.apache.org/data-format.html">data format</a>
* ({@link DataFormat}) interface which leverage the XStream library for XML or JSON's marshaling and unmarshaling
*
* @version $Revision: 962504 $
*/
public abstract class AbstractXStreamWrapper implements DataFormat {
private XStream xstream;
private StaxConverter staxConverter;
private List<String> converters;
private Map<String, String> aliases;
private Map<String, String[]> implicitCollections;
public AbstractXStreamWrapper() {
}
public AbstractXStreamWrapper(XStream xstream) {
this.xstream = xstream;
}
public XStream getXStream(ClassResolver resolver) {
if (xstream == null) {
xstream = createXStream(resolver);
}
return xstream;
}
public void setXStream(XStream xstream) {
this.xstream = xstream;
}
protected XStream createXStream(ClassResolver resolver) {
xstream = new XStream();
try {
if (this.implicitCollections != null) {
for (Entry<String, String[]> entry : this.implicitCollections.entrySet()) {
for (String name : entry.getValue()) {
xstream.addImplicitCollection(resolver.resolveMandatoryClass(entry.getKey()), name);
}
}
}
if (this.aliases != null) {
for (Entry<String, String> entry : this.aliases.entrySet()) {
xstream.alias(entry.getKey(), resolver.resolveMandatoryClass(entry.getValue()));
}
}
if (this.converters != null) {
for (String name : this.converters) {
Class<Converter> converterClass = resolver.resolveMandatoryClass(name, Converter.class);
Converter converter;
Constructor con = null;
try {
con = converterClass.getDeclaredConstructor(new Class[] {XStream.class});
} catch (Exception e) {
//swallow as we null check in a moment.
}
if (con != null) {
converter = (Converter) con.newInstance(xstream);
} else {
converter = converterClass.newInstance();
try {
Method method = converterClass.getMethod("setXStream", new Class[] {XStream.class});
if (method != null) {
ObjectHelper.invokeMethod(method, converter, xstream);
}
} catch (Throwable e) {
// swallow, as it just means the user never add an XStream setter, which is optional
}
}
xstream.registerConverter(converter);
}
}
} catch (Exception e) {
throw new RuntimeException("Unable to build XStream instance", e);
}
return xstream;
}
public StaxConverter getStaxConverter() {
if (staxConverter == null) {
staxConverter = new StaxConverter();
}
return staxConverter;
}
public void setStaxConverter(StaxConverter staxConverter) {
this.staxConverter = staxConverter;
}
public List<String> getConverters() {
return converters;
}
public void setConverters(List<String> converters) {
this.converters = converters;
}
public Map<String, String> getAliases() {
return aliases;
}
public void setAliases(Map<String, String> aliases) {
this.aliases = aliases;
}
public Map<String, String[]> getImplicitCollections() {
return implicitCollections;
}
public void setImplicitCollections(Map<String, String[]> implicitCollections) {
this.implicitCollections = implicitCollections;
}
public XStream getXstream() {
return xstream;
}
public void setXstream(XStream xstream) {
this.xstream = xstream;
}
public void marshal(Exchange exchange, Object body, OutputStream stream) throws Exception {
HierarchicalStreamWriter writer = createHierarchicalStreamWriter(exchange, body, stream);
try {
getXStream(exchange.getContext().getClassResolver()).marshal(body, writer);
} finally {
writer.close();
}
}
public Object unmarshal(Exchange exchange, InputStream stream) throws Exception {
HierarchicalStreamReader reader = createHierarchicalStreamReader(exchange, stream);
try {
return getXStream(exchange.getContext().getClassResolver()).unmarshal(reader);
} finally {
reader.close();
}
}
protected abstract HierarchicalStreamWriter createHierarchicalStreamWriter(
Exchange exchange, Object body, OutputStream stream) throws XMLStreamException;
protected abstract HierarchicalStreamReader createHierarchicalStreamReader(
Exchange exchange, InputStream stream) throws XMLStreamException;
}