/***
* Copyright (c) 2009 Caelum - www.caelum.com.br/opensource All rights reserved.
*
* Licensed 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 br.com.caelum.vraptor.serialization.xstream;
import java.io.IOException;
import java.io.Writer;
import javax.servlet.http.HttpServletResponse;
import br.com.caelum.vraptor.interceptor.TypeNameExtractor;
import br.com.caelum.vraptor.ioc.Component;
import br.com.caelum.vraptor.serialization.JSONSerialization;
import br.com.caelum.vraptor.serialization.NoRootSerialization;
import br.com.caelum.vraptor.serialization.ProxyInitializer;
import br.com.caelum.vraptor.serialization.Serializer;
import br.com.caelum.vraptor.serialization.SerializerBuilder;
import br.com.caelum.vraptor.view.ResultException;
import com.thoughtworks.xstream.XStream;
import com.thoughtworks.xstream.io.HierarchicalStreamDriver;
import com.thoughtworks.xstream.io.HierarchicalStreamWriter;
import com.thoughtworks.xstream.io.json.JsonHierarchicalStreamDriver;
import com.thoughtworks.xstream.io.json.JsonWriter;
import com.thoughtworks.xstream.mapper.MapperWrapper;
/**
* XStream implementation for JSONSerialization
*
* @author Lucas Cavalcanti
* @since 3.0.2
*/
@Component
public class XStreamJSONSerialization implements JSONSerialization {
protected final HttpServletResponse response;
protected final TypeNameExtractor extractor;
protected final ProxyInitializer initializer;
private HierarchicalStreamDriver driver;
private boolean withoutRoot;
private boolean indented;
protected static final String DEFAULT_NEW_LINE = "";
protected static final char[] DEFAULT_LINE_INDENTER = {};
protected static final String INDENTED_NEW_LINE = "\n";
protected static final char[] INDENTED_LINE_INDENTER = { ' ', ' '};
public XStreamJSONSerialization(HttpServletResponse response, TypeNameExtractor extractor, ProxyInitializer initializer) {
this.response = response;
this.extractor = extractor;
this.initializer = initializer;
}
public boolean accepts(String format) {
return "json".equals(format);
}
public <T> Serializer from(T object) {
return from(object, null);
}
public <T> Serializer from(T object, String alias) {
final String newLine = (indented ? INDENTED_NEW_LINE : DEFAULT_NEW_LINE);
final char[] lineIndenter = (indented ? INDENTED_LINE_INDENTER : DEFAULT_LINE_INDENTER);
driver = new JsonHierarchicalStreamDriver() {
public HierarchicalStreamWriter createWriter(Writer writer) {
if (withoutRoot) {
return new JsonWriter(writer, lineIndenter, newLine, JsonWriter.DROP_ROOT_MODE);
}
return new JsonWriter(writer, lineIndenter, newLine);
}
};
response.setContentType("application/json");
return getSerializer().from(object, alias);
}
protected SerializerBuilder getSerializer() {
try {
return new XStreamSerializer(getXStream(), response.getWriter(), extractor, initializer);
} catch (IOException e) {
throw new ResultException("Unable to serialize data", e);
}
}
/**
* You can override this method for configuring XStream before serialization
*/
protected XStream getXStream() {
return new XStream(getHierarchicalStreamDriver()) {
{setMode(NO_REFERENCES);}
@Override
protected MapperWrapper wrapMapper(MapperWrapper next) {
return new VRaptorClassMapper(next, extractor);
}
};
}
/**
* You can override this method for configuring Driver before serialization
*/
protected HierarchicalStreamDriver getHierarchicalStreamDriver() {
return this.driver;
}
public <T> NoRootSerialization withoutRoot() {
withoutRoot = true;
return this;
}
public JSONSerialization indented() {
indented = true;
return this;
}
}