001/*
002 *
003 * Licensed to the Apache Software Foundation (ASF) under one
004 * or more contributor license agreements.  See the NOTICE file
005 * distributed with this work for additional information
006 * regarding copyright ownership.  The ASF licenses this file
007 * to you under the Apache License, Version 2.0 (the
008 * "License"); you may not use this file except in compliance
009 * with the License.  You may obtain a copy of the License at
010 *
011 *     http://www.apache.org/licenses/LICENSE-2.0
012 *
013 * Unless required by applicable law or agreed to in writing, software
014 * distributed under the License is distributed on an "AS IS" BASIS,
015 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
016 * See the License for the specific language governing permissions and
017 * limitations under the License.
018 */
019
020package org.apache.hadoop.hbase.rest.provider.producer;
021
022import java.io.IOException;
023import java.io.OutputStream;
024import java.lang.annotation.Annotation;
025import java.lang.reflect.Type;
026
027import javax.ws.rs.Produces;
028import javax.ws.rs.WebApplicationException;
029import javax.ws.rs.core.MediaType;
030import javax.ws.rs.core.MultivaluedMap;
031import javax.ws.rs.ext.MessageBodyWriter;
032import javax.ws.rs.ext.Provider;
033
034import org.apache.hadoop.hbase.rest.Constants;
035import org.apache.hadoop.hbase.rest.ProtobufMessageHandler;
036import org.apache.yetus.audience.InterfaceAudience;
037
038/**
039 * An adapter between Jersey and ProtobufMessageHandler implementors. Hooks up
040 * protobuf output producing methods to the Jersey content handling framework.
041 * Jersey will first call getSize() to learn the number of bytes that will be
042 * sent, then writeTo to perform the actual I/O.
043 */
044@Provider
045@Produces({Constants.MIMETYPE_PROTOBUF, Constants.MIMETYPE_PROTOBUF_IETF})
046@InterfaceAudience.Private
047public class ProtobufMessageBodyProducer
048  implements MessageBodyWriter<ProtobufMessageHandler> {
049
050  @Override
051  public boolean isWriteable(Class<?> type, Type genericType, 
052      Annotation[] annotations, MediaType mediaType) {
053    return ProtobufMessageHandler.class.isAssignableFrom(type);
054  }
055
056  @Override
057  public long getSize(ProtobufMessageHandler m, Class<?> type, Type genericType,
058      Annotation[] annotations, MediaType mediaType) {
059    // deprecated by JAX-RS 2.0 and ignored by Jersey runtime
060    return -1;
061  }
062
063  @Override
064  public void writeTo(ProtobufMessageHandler m, Class<?> type, Type genericType,
065      Annotation[] annotations, MediaType mediaType, 
066      MultivaluedMap<String, Object> httpHeaders, OutputStream entityStream) 
067      throws IOException, WebApplicationException {
068    entityStream.write(m.createProtobufOutput());
069  }
070}