/*
* Copyright (C) 2009 eXo Platform SAS.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.exoplatform.services.rest.impl.provider;
import org.exoplatform.services.rest.provider.EntityProvider;
import org.exoplatform.ws.frameworks.json.JsonHandler;
import org.exoplatform.ws.frameworks.json.JsonParser;
import org.exoplatform.ws.frameworks.json.JsonWriter;
import org.exoplatform.ws.frameworks.json.impl.BeanBuilder;
import org.exoplatform.ws.frameworks.json.impl.JsonDefaultHandler;
import org.exoplatform.ws.frameworks.json.impl.JsonException;
import org.exoplatform.ws.frameworks.json.impl.JsonGeneratorImpl;
import org.exoplatform.ws.frameworks.json.impl.JsonParserImpl;
import org.exoplatform.ws.frameworks.json.impl.JsonWriterImpl;
import org.exoplatform.ws.frameworks.json.value.JsonValue;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.Reader;
import java.io.Writer;
import java.lang.annotation.Annotation;
import java.lang.reflect.Type;
import javax.activation.DataSource;
import javax.ws.rs.Consumes;
import javax.ws.rs.Produces;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.MultivaluedMap;
import javax.ws.rs.core.StreamingOutput;
import javax.ws.rs.ext.Provider;
import javax.xml.bind.JAXBElement;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.sax.SAXSource;
import javax.xml.transform.stream.StreamSource;
/**
* @author <a href="mailto:andrew00x@gmail.com">Andrey Parfonov</a>
* @version $Id: $
*/
@Provider
@Consumes({MediaType.APPLICATION_JSON})
@Produces({MediaType.APPLICATION_JSON})
public class JsonEntityProvider implements EntityProvider<Object>
{
// It is common task for #isReadable() and #isWriteable
// TODO Not sure it is required but ...
// Investigation about checking can type be write as JSON (useful JSON).
// Probably should be better added this checking in JSON framework.
// Or probably enough check only content type 'application/json'
// and if this content type set trust it and try parse/write
/** Do not process via JSON "known" JAX-RS types and some more. */
private static final Class<?>[] IGNORED =
new Class<?>[]{byte[].class, char[].class, DataSource.class, DOMSource.class, File.class, InputStream.class,
OutputStream.class, JAXBElement.class, MultivaluedMap.class, Reader.class, Writer.class, SAXSource.class,
StreamingOutput.class, StreamSource.class, String.class};
private static boolean isIgnored(Class<?> type)
{
for (Class<?> c : IGNORED)
{
if (c.isAssignableFrom(type))
{
return true;
}
}
return false;
}
/**
* {@inheritDoc}
*/
public boolean isReadable(Class<?> type, Type genericType, Annotation[] annotations, MediaType mediaType)
{
//return Object.class.isAssignableFrom(type);
return !isIgnored(type);
}
/**
* {@inheritDoc}
*/
public Object readFrom(Class<Object> type, Type genericType, Annotation[] annotations, MediaType mediaType,
MultivaluedMap<String, String> httpHeaders, InputStream entityStream) throws IOException
{
try
{
JsonParser jsonParser = new JsonParserImpl();
JsonHandler jsonHandler = new JsonDefaultHandler();
jsonParser.parse(entityStream, jsonHandler);
JsonValue jsonValue = jsonHandler.getJsonObject();
// jsonValue can be null if stream empty
if (jsonValue == null)
return null;
return new BeanBuilder().createObject(type, jsonValue);
}
catch (Exception e)
{
throw new IOException("Can't read from input stream " + e);
}
}
/**
* {@inheritDoc}
*/
public long getSize(Object t, Class<?> type, Type genericType, Annotation[] annotations, MediaType mediaType)
{
return -1;
}
/**
* {@inheritDoc}
*/
public boolean isWriteable(Class<?> type, Type genericType, Annotation[] annotations, MediaType mediaType)
{
//return Object.class.isAssignableFrom(type);
return !isIgnored(type);
}
/**
* {@inheritDoc}
*/
public void writeTo(Object t, Class<?> type, Type genericType, Annotation[] annotations, MediaType mediaType,
MultivaluedMap<String, Object> httpHeaders, OutputStream entityStream) throws IOException
{
try
{
JsonValue jv = new JsonGeneratorImpl().createJsonObject(t);
JsonWriter jsonWriter = new JsonWriterImpl(entityStream);
jv.writeTo(jsonWriter);
jsonWriter.flush();
}
catch (JsonException e)
{
throw new IOException("Can't write to output stream " + e);
}
}
}