/*
* 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.shindig.protocol.conversion;
import org.apache.shindig.protocol.ContentTypes;
import org.apache.shindig.protocol.DataCollection;
import org.apache.shindig.protocol.RestfulCollection;
import org.apache.shindig.protocol.conversion.xstream.StackDriver;
import org.apache.shindig.protocol.conversion.xstream.ThreadSafeWriterStack;
import org.apache.shindig.protocol.conversion.xstream.WriterStack;
import org.apache.shindig.protocol.conversion.xstream.XStreamConfiguration;
import com.google.common.collect.Maps;
import com.google.inject.Inject;
import com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider;
import com.thoughtworks.xstream.converters.reflection.ReflectionProvider;
import com.thoughtworks.xstream.io.HierarchicalStreamDriver;
import com.thoughtworks.xstream.io.xml.XppDriver;
import com.thoughtworks.xstream.mapper.DefaultMapper;
import com.thoughtworks.xstream.mapper.Mapper;
import java.io.IOException;
import java.util.Map;
import java.util.logging.Logger;
import java.util.logging.Level;
public class BeanXStreamConverter implements BeanConverter {
public static final String XML_DECL = "<?xml version=\"1.0\" encoding=\"UTF-8\"?>";
private static final XStreamConfiguration.ConverterSet[] MAPPER_SCOPES = {
XStreamConfiguration.ConverterSet.MAP,
XStreamConfiguration.ConverterSet.COLLECTION,
XStreamConfiguration.ConverterSet.DEFAULT };
private static final Logger LOG = Logger.getLogger(BeanXStreamConverter.class.getName());
private ReflectionProvider rp;
private HierarchicalStreamDriver driver;
protected WriterStack writerStack;
protected Map<XStreamConfiguration.ConverterSet, XStreamConfiguration.ConverterConfig> converterMap = Maps.newHashMap();
@Inject
public BeanXStreamConverter(XStreamConfiguration configuration) {
rp = new PureJavaReflectionProvider();
Mapper dmapper = new DefaultMapper(this.getClass().getClassLoader());
/*
* Putting this here means only one conversion per thread may be active at
* any one time, but since the conversion process is atomic this will not
* matter unless the class is extended.
*/
writerStack = new ThreadSafeWriterStack();
/*
* create a driver that wires into a standard driver, and updates the stack
* position.
*/
driver = new StackDriver(new XppDriver(), writerStack, configuration.getNameSpaces());
/*
* Create an interface class mapper that understands class hierarchy for
* single items
*/
for (XStreamConfiguration.ConverterSet c : MAPPER_SCOPES) {
converterMap.put(c, configuration.getConverterConfig(c,rp,dmapper,driver,writerStack));
}
}
public String getContentType() {
return ContentTypes.OUTPUT_XML_CONTENT_TYPE;
}
public String convertToString(Object pojo) {
return convertToXml(pojo);
}
/**
* convert an Object to XML, but make certain that only one of these is run on
* a thread at any one time. This only matters if this class is extended.
*
* @param obj
* @return The XML as a string
*/
private String convertToXml(Object obj) {
writerStack.reset();
if (obj instanceof Map<?, ?>) {
Map<?, ?> m = (Map<?, ?>) obj;
XStreamConfiguration.ConverterConfig cc = converterMap
.get(XStreamConfiguration.ConverterSet.MAP);
if (m.size() == 1) {
Object s = m.values().iterator().next();
cc.mapper.setBaseObject(s); // thread safe method
String result = cc.xstream.toXML(s);
if (LOG.isLoggable(Level.FINE))
LOG.fine("Result is " + result);
return XML_DECL + "<response xmlns=\"http://ns.opensocial.org/2008/opensocial\">" + result + "</response>";
}
} else if (obj instanceof RestfulCollection) {
XStreamConfiguration.ConverterConfig cc = converterMap
.get(XStreamConfiguration.ConverterSet.COLLECTION);
cc.mapper.setBaseObject(obj); // thread safe method
String result = cc.xstream.toXML(obj);
if (LOG.isLoggable(Level.FINE))
LOG.fine("Result is " + result);
return XML_DECL + result;
} else if (obj instanceof DataCollection) {
XStreamConfiguration.ConverterConfig cc = converterMap
.get(XStreamConfiguration.ConverterSet.MAP);
cc.mapper.setBaseObject(obj); // thread safe method
String result = cc.xstream.toXML(obj);
if (LOG.isLoggable(Level.FINE))
LOG.fine("Result is " + result);
return XML_DECL + result;
}
XStreamConfiguration.ConverterConfig cc = converterMap
.get(XStreamConfiguration.ConverterSet.DEFAULT);
cc.mapper.setBaseObject(obj); // thread safe method
String result = cc.xstream.toXML(obj);
if (LOG.isLoggable(Level.FINE))
LOG.fine("Result is " + result);
return XML_DECL + "<response xmlns=\"http://ns.opensocial.org/2008/opensocial\">" + result + "</response>";
}
@SuppressWarnings("unchecked")
public <T> T convertToObject(String xml, Class<T> className) {
XStreamConfiguration.ConverterConfig cc = converterMap.get(XStreamConfiguration.ConverterSet.DEFAULT);
return (T) cc.xstream.fromXML(xml);
}
public void append(Appendable buf, Object pojo) throws IOException {
buf.append(convertToString(pojo));
}
}