| /** |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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.apache.avro.mapred.tether; |
| |
| import java.io.IOException; |
| |
| import org.apache.hadoop.io.NullWritable; |
| import org.apache.hadoop.mapred.JobConf; |
| import org.apache.hadoop.mapred.FileSplit; |
| import org.apache.hadoop.mapred.RecordReader; |
| |
| import org.apache.avro.Schema; |
| import org.apache.avro.file.DataFileReader; |
| import org.apache.avro.generic.GenericDatumReader; |
| import org.apache.avro.mapred.AvroJob; |
| import org.apache.avro.mapred.FsInput; |
| |
| class TetherRecordReader |
| implements RecordReader<TetherData, NullWritable> { |
| |
| private FsInput in; |
| private DataFileReader reader; |
| private long start; |
| private long end; |
| |
| public TetherRecordReader(JobConf job, FileSplit split) |
| throws IOException { |
| this.in = new FsInput(split.getPath(), job); |
| this.reader = |
| new DataFileReader<Object>(in, new GenericDatumReader<Object>()); |
| |
| reader.sync(split.getStart()); // sync to start |
| this.start = in.tell(); |
| this.end = split.getStart() + split.getLength(); |
| |
| job.set(AvroJob.INPUT_SCHEMA, reader.getSchema().toString()); |
| } |
| |
| public Schema getSchema() { return reader.getSchema(); } |
| |
| public TetherData createKey() { return new TetherData(); } |
| |
| public NullWritable createValue() { return NullWritable.get(); } |
| |
| public boolean next(TetherData data, NullWritable ignore) |
| throws IOException { |
| if (!reader.hasNext() || reader.pastSync(end)) |
| return false; |
| data.buffer(reader.nextBlock()); |
| data.count((int)reader.getBlockCount()); |
| return true; |
| } |
| |
| public float getProgress() throws IOException { |
| if (end == start) { |
| return 0.0f; |
| } else { |
| return Math.min(1.0f, (in.tell() - start) / (float)(end - start)); |
| } |
| } |
| |
| public long getPos() throws IOException { |
| return in.tell(); |
| } |
| |
| public void close() throws IOException { reader.close(); } |
| |
| } |