001/** 002 * Licensed to the Apache Software Foundation (ASF) under one 003 * or more contributor license agreements. See the NOTICE file 004 * distributed with this work for additional information 005 * regarding copyright ownership. The ASF licenses this file 006 * to you under the Apache License, Version 2.0 (the 007 * "License"); you may not use this file except in compliance 008 * with the License. You may obtain a copy of the License at 009 * 010 * http://www.apache.org/licenses/LICENSE-2.0 011 * 012 * Unless required by applicable law or agreed to in writing, software 013 * distributed under the License is distributed on an "AS IS" BASIS, 014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 015 * See the License for the specific language governing permissions and 016 * limitations under the License. 017 */ 018package org.apache.hadoop.hdfs.server.datanode.web.resources; 019 020import java.io.IOException; 021import java.io.OutputStream; 022import java.lang.annotation.Annotation; 023import java.lang.reflect.Type; 024 025import javax.ws.rs.core.MediaType; 026import javax.ws.rs.core.MultivaluedMap; 027import javax.ws.rs.ext.MessageBodyWriter; 028import javax.ws.rs.ext.Provider; 029 030import org.apache.hadoop.hdfs.DFSClient; 031import org.apache.hadoop.hdfs.client.HdfsDataInputStream; 032import org.apache.hadoop.io.IOUtils; 033 034/** 035 * A response entity for a HdfsDataInputStream. 036 */ 037public class OpenEntity { 038 private final HdfsDataInputStream in; 039 private final long length; 040 private final DFSClient dfsclient; 041 042 OpenEntity(final HdfsDataInputStream in, final long length, 043 final DFSClient dfsclient) { 044 this.in = in; 045 this.length = length; 046 this.dfsclient = dfsclient; 047 } 048 049 /** 050 * A {@link MessageBodyWriter} for {@link OpenEntity}. 051 */ 052 @Provider 053 public static class Writer implements MessageBodyWriter<OpenEntity> { 054 055 @Override 056 public boolean isWriteable(Class<?> clazz, Type genericType, 057 Annotation[] annotations, MediaType mediaType) { 058 return clazz == OpenEntity.class 059 && MediaType.APPLICATION_OCTET_STREAM_TYPE.isCompatible(mediaType); 060 } 061 062 @Override 063 public long getSize(OpenEntity e, Class<?> type, Type genericType, 064 Annotation[] annotations, MediaType mediaType) { 065 return e.length; 066 } 067 068 @Override 069 public void writeTo(OpenEntity e, Class<?> type, Type genericType, 070 Annotation[] annotations, MediaType mediaType, 071 MultivaluedMap<String, Object> httpHeaders, OutputStream out 072 ) throws IOException { 073 try { 074 IOUtils.copyBytes(e.in, out, e.length, false); 075 } finally { 076 IOUtils.cleanup(DatanodeWebHdfsMethods.LOG, e.in); 077 IOUtils.cleanup(DatanodeWebHdfsMethods.LOG, e.dfsclient); 078 } 079 } 080 } 081}