/*
* Copyright 2010 Outerthought bvba
*
* 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 org.lilyproject.rest.providers.json;
import javax.ws.rs.WebApplicationException;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.MultivaluedMap;
import javax.ws.rs.core.Response;
import javax.ws.rs.ext.MessageBodyWriter;
import javax.ws.rs.ext.Provider;
import java.io.IOException;
import java.io.OutputStream;
import java.lang.annotation.Annotation;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import org.apache.commons.io.output.CloseShieldOutputStream;
import org.codehaus.jackson.node.ArrayNode;
import org.codehaus.jackson.node.JsonNodeFactory;
import org.codehaus.jackson.node.ObjectNode;
import org.lilyproject.rest.BaseRepositoryResource;
import org.lilyproject.rest.EntityList;
import org.lilyproject.rest.ResourceException;
import org.lilyproject.tools.import_.json.EntityWriter;
import org.lilyproject.util.json.JsonFormat;
@Provider
public class EntityListMessageBodyWriter extends BaseRepositoryResource implements MessageBodyWriter<EntityList> {
@Override
public boolean isWriteable(Class<?> type, Type genericType, Annotation[] annotations, MediaType mediaType) {
return type.equals(EntityList.class) && isTypeParamSupported(genericType) && mediaType.equals(MediaType.APPLICATION_JSON_TYPE);
}
public boolean isTypeParamSupported(Type genericType) {
if (genericType instanceof ParameterizedType) {
ParameterizedType pt = (ParameterizedType)genericType;
Type[] types = pt.getActualTypeArguments();
if (types.length == 1 && EntityRegistry.SUPPORTED_TYPES.containsKey(types[0])) {
return true;
}
}
return false;
}
protected EntityWriter getEntityWriter(Type genericType) {
Class kind = (Class)((ParameterizedType)genericType).getActualTypeArguments()[0];
return EntityRegistry.SUPPORTED_TYPES.get(kind).getWriter();
}
@Override
public long getSize(EntityList entityList, Class<?> type, Type genericType, Annotation[] annotations, MediaType mediaType) {
return -1;
}
@Override
public void writeTo(EntityList entityList, Class<?> type, Type genericType, Annotation[] annotations,
MediaType mediaType, MultivaluedMap<String, Object> httpHeaders, OutputStream entityStream)
throws IOException, WebApplicationException {
try {
ObjectNode listNode = JsonNodeFactory.instance.objectNode();
ArrayNode resultsNode = listNode.putArray("results");
EntityWriter writer = getEntityWriter(genericType);
for (Object entity : entityList.getEntities()) {
// Multiple repositories: ok to use public repo since only non-repository-specific things are needed
resultsNode.add(writer.toJson(entity, entityList.getWriteOptions(),
repositoryMgr.getDefaultRepository()));
}
JsonFormat.serialize(listNode, new CloseShieldOutputStream(entityStream));
} catch (Throwable e) {
// We catch every throwable, since otherwise no one does it and we will not have any trace
// of Errors that happened.
throw new ResourceException("Error serializing entity list.", e, Response.Status.INTERNAL_SERVER_ERROR.getStatusCode());
}
}
}