/***
* 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.deserialization;
import static com.google.common.base.Preconditions.checkArgument;
import java.io.InputStream;
import java.lang.reflect.Method;
import br.com.caelum.vraptor.http.ParameterNameProvider;
import br.com.caelum.vraptor.interceptor.TypeNameExtractor;
import br.com.caelum.vraptor.resource.ResourceMethod;
import br.com.caelum.vraptor.serialization.xstream.VRaptorXStream;
import br.com.caelum.vraptor.serialization.xstream.XStreamBuilder;
import com.thoughtworks.xstream.XStream;
import com.thoughtworks.xstream.io.HierarchicalStreamDriver;
import com.thoughtworks.xstream.io.json.JettisonMappedXmlDriver;
/**
*
* @author Guilherme Silveira
* @since 3.1.3
*/
@Deserializes({"application/json","json"})
public class JsonDeserializer implements Deserializer{
private final ParameterNameProvider provider;
private final XStreamBuilder builder;
private final TypeNameExtractor extractor;
public JsonDeserializer(ParameterNameProvider provider,TypeNameExtractor extractor, XStreamBuilder builder) {
this.provider = provider;
this.extractor = extractor;
this.builder = builder;
}
public Object[] deserialize(InputStream inputStream, ResourceMethod method) {
Method javaMethod = method.getMethod();
Class<?>[] types = javaMethod.getParameterTypes();
checkArgument(types.length > 0,
"Methods that consumes representations must receive just one argument: the root element");
XStream xStream = getConfiguredXStream(javaMethod, types);
Object[] params = new Object[types.length];
chooseParam(types, params, xStream.fromXML(inputStream));
return params;
}
/**
* Returns an xstream instance already configured.
*/
public XStream getConfiguredXStream(Method javaMethod, Class<?>[] types) {
XStream xStream = getXStream();
aliasParams(javaMethod, types, xStream);
return builder.configure(xStream);
}
private void chooseParam(Class<?>[] types, Object[] params, Object deserialized) {
for (int i = 0; i < types.length; i++) {
if (types[i].isInstance(deserialized)) {
params[i] = deserialized;
}
}
}
private void aliasParams(Method method, Class<?>[] types, XStream deserializer) {
String[] names = provider.parameterNamesFor(method);
for (int i = 0; i < names.length; i++) {
deserializer.alias(names[i], types[i]);
}
}
/**
* Extension point to configure your xstream instance.
* @return the configured xstream instance
*/
protected XStream getXStream() {
return new VRaptorXStream(extractor, getHierarchicalStreamDriver());
}
/**
* You can override this method for configuring Driver before serialization
*/
protected HierarchicalStreamDriver getHierarchicalStreamDriver() {
return new JettisonMappedXmlDriver();
}
}