/**
* 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.activemq.transport.stomp;
import java.io.IOException;
import java.io.Serializable;
import java.io.StringReader;
import java.io.StringWriter;
import java.util.HashMap;
import java.util.Map;
import javax.jms.JMSException;
import org.apache.activemq.command.ActiveMQMapMessage;
import org.apache.activemq.command.ActiveMQMessage;
import org.apache.activemq.command.ActiveMQObjectMessage;
import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import com.thoughtworks.xstream.XStream;
import com.thoughtworks.xstream.io.HierarchicalStreamReader;
import com.thoughtworks.xstream.io.HierarchicalStreamWriter;
import com.thoughtworks.xstream.io.json.JettisonMappedXmlDriver;
import com.thoughtworks.xstream.io.xml.PrettyPrintWriter;
import com.thoughtworks.xstream.io.xml.XppReader;
/**
* Frame translator implementation that uses XStream to convert messages to and
* from XML and JSON
*
* @author <a href="mailto:dejan@nighttale.net">Dejan Bosanac</a>
*/
public class JmsFrameTranslator extends LegacyFrameTranslator implements
ApplicationContextAware {
XStream xStream = null;
ApplicationContext applicationContext;
public ActiveMQMessage convertFrame(ProtocolConverter converter,
StompFrame command) throws JMSException, ProtocolException {
Map headers = command.getHeaders();
ActiveMQMessage msg;
String transformation = (String) headers.get(Stomp.Headers.TRANSFORMATION);
if (headers.containsKey(Stomp.Headers.CONTENT_LENGTH) || transformation.equals(Stomp.Transformations.JMS_BYTE.toString())) {
msg = super.convertFrame(converter, command);
} else {
HierarchicalStreamReader in;
try {
String text = new String(command.getContent(), "UTF-8");
switch (Stomp.Transformations.getValue(transformation)) {
case JMS_OBJECT_XML:
in = new XppReader(new StringReader(text));
msg = createObjectMessage(in);
break;
case JMS_OBJECT_JSON:
in = new JettisonMappedXmlDriver().createReader(new StringReader(text));
msg = createObjectMessage(in);
break;
case JMS_MAP_XML:
in = new XppReader(new StringReader(text));
msg = createMapMessage(in);
break;
case JMS_MAP_JSON:
in = new JettisonMappedXmlDriver().createReader(new StringReader(text));
msg = createMapMessage(in);
break;
default:
throw new Exception("Unkown transformation: " + transformation);
}
} catch (Throwable e) {
command.getHeaders().put(Stomp.Headers.TRANSFORMATION_ERROR, e.getMessage());
msg = super.convertFrame(converter, command);
}
}
FrameTranslator.Helper.copyStandardHeadersFromFrameToMessage(converter, command, msg, this);
return msg;
}
public StompFrame convertMessage(ProtocolConverter converter,
ActiveMQMessage message) throws IOException, JMSException {
if (message.getDataStructureType() == ActiveMQObjectMessage.DATA_STRUCTURE_TYPE) {
StompFrame command = new StompFrame();
command.setAction(Stomp.Responses.MESSAGE);
Map<String, String> headers = new HashMap<String, String>(25);
command.setHeaders(headers);
FrameTranslator.Helper.copyStandardHeadersFromMessageToFrame(
converter, message, command, this);
ActiveMQObjectMessage msg = (ActiveMQObjectMessage) message.copy();
command.setContent(marshall(msg.getObject(),
headers.get(Stomp.Headers.TRANSFORMATION))
.getBytes("UTF-8"));
return command;
} else if (message.getDataStructureType() == ActiveMQMapMessage.DATA_STRUCTURE_TYPE) {
StompFrame command = new StompFrame();
command.setAction(Stomp.Responses.MESSAGE);
Map<String, String> headers = new HashMap<String, String>(25);
command.setHeaders(headers);
FrameTranslator.Helper.copyStandardHeadersFromMessageToFrame(
converter, message, command, this);
ActiveMQMapMessage msg = (ActiveMQMapMessage) message.copy();
command.setContent(marshall((Serializable)msg.getContentMap(),
headers.get(Stomp.Headers.TRANSFORMATION))
.getBytes("UTF-8"));
return command;
} else {
return super.convertMessage(converter, message);
}
}
/**
* Marshalls the Object to a string using XML or JSON encoding
*/
protected String marshall(Serializable object, String transformation)
throws JMSException {
StringWriter buffer = new StringWriter();
HierarchicalStreamWriter out;
if (transformation.toLowerCase().endsWith("json")) {
out = new JettisonMappedXmlDriver().createWriter(buffer);
} else {
out = new PrettyPrintWriter(buffer);
}
getXStream().marshal(object, out);
return buffer.toString();
}
protected ActiveMQObjectMessage createObjectMessage(HierarchicalStreamReader in) throws JMSException {
ActiveMQObjectMessage objMsg = new ActiveMQObjectMessage();
Object obj = getXStream().unmarshal(in);
objMsg.setObject((Serializable) obj);
return objMsg;
}
protected ActiveMQMapMessage createMapMessage(HierarchicalStreamReader in) throws JMSException {
ActiveMQMapMessage mapMsg = new ActiveMQMapMessage();
Map<String, Object> map = (Map<String, Object>)getXStream().unmarshal(in);
for (String key : map.keySet()) {
mapMsg.setObject(key, map.get(key));
}
return mapMsg;
}
// Properties
// -------------------------------------------------------------------------
public XStream getXStream() {
if (xStream == null) {
xStream = createXStream();
}
return xStream;
}
public void setXStream(XStream xStream) {
this.xStream = xStream;
}
// Implementation methods
// -------------------------------------------------------------------------
protected XStream createXStream() {
XStream xstream = null;
if (applicationContext != null) {
String[] names = applicationContext
.getBeanNamesForType(XStream.class);
for (int i = 0; i < names.length; i++) {
String name = names[i];
xstream = (XStream) applicationContext.getBean(name);
if (xstream != null) {
break;
}
}
}
if (xstream == null) {
System.out.println("is null");
xstream = new XStream();
}
return xstream;
}
public void setApplicationContext(ApplicationContext applicationContext)
throws BeansException {
this.applicationContext = applicationContext;
}
}