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 */
018
019 package org.apache.hadoop.mapred;
020
021 import java.io.IOException;
022 import java.io.DataInput;
023 import java.io.DataOutput;
024
025 import org.apache.hadoop.classification.InterfaceAudience;
026 import org.apache.hadoop.classification.InterfaceStability;
027 import org.apache.hadoop.fs.Path;
028
029 /** A section of an input file. Returned by {@link
030 * InputFormat#getSplits(JobConf, int)} and passed to
031 * {@link InputFormat#getRecordReader(InputSplit,JobConf,Reporter)}.
032 */
033 @InterfaceAudience.Public
034 @InterfaceStability.Stable
035 public class FileSplit extends org.apache.hadoop.mapreduce.InputSplit
036 implements InputSplit {
037 org.apache.hadoop.mapreduce.lib.input.FileSplit fs;
038 protected FileSplit() {
039 fs = new org.apache.hadoop.mapreduce.lib.input.FileSplit();
040 }
041
042 /** Constructs a split.
043 * @deprecated
044 * @param file the file name
045 * @param start the position of the first byte in the file to process
046 * @param length the number of bytes in the file to process
047 */
048 @Deprecated
049 public FileSplit(Path file, long start, long length, JobConf conf) {
050 this(file, start, length, (String[])null);
051 }
052
053 /** Constructs a split with host information
054 *
055 * @param file the file name
056 * @param start the position of the first byte in the file to process
057 * @param length the number of bytes in the file to process
058 * @param hosts the list of hosts containing the block, possibly null
059 */
060 public FileSplit(Path file, long start, long length, String[] hosts) {
061 fs = new org.apache.hadoop.mapreduce.lib.input.FileSplit(file, start,
062 length, hosts);
063 }
064
065 public FileSplit(org.apache.hadoop.mapreduce.lib.input.FileSplit fs) {
066 this.fs = fs;
067 }
068
069 /** The file containing this split's data. */
070 public Path getPath() { return fs.getPath(); }
071
072 /** The position of the first byte in the file to process. */
073 public long getStart() { return fs.getStart(); }
074
075 /** The number of bytes in the file to process. */
076 public long getLength() { return fs.getLength(); }
077
078 public String toString() { return fs.toString(); }
079
080 ////////////////////////////////////////////
081 // Writable methods
082 ////////////////////////////////////////////
083
084 public void write(DataOutput out) throws IOException {
085 fs.write(out);
086 }
087 public void readFields(DataInput in) throws IOException {
088 fs.readFields(in);
089 }
090
091 public String[] getLocations() throws IOException {
092 return fs.getLocations();
093 }
094
095 }