org.apache.hadoop.mapreduce.lib.input.SequenceFileInputFormat.java Source code

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Here is the source code for org.apache.hadoop.mapreduce.lib.input.SequenceFileInputFormat.java

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/**
 * 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.hadoop.mapreduce.lib.input;

import java.io.IOException;
import java.util.List;

import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.classification.InterfaceStability;
import org.apache.hadoop.fs.FileStatus;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;

import org.apache.hadoop.io.SequenceFile;
import org.apache.hadoop.io.MapFile;
import org.apache.hadoop.mapreduce.InputFormat;
import org.apache.hadoop.mapreduce.InputSplit;
import org.apache.hadoop.mapreduce.JobContext;
import org.apache.hadoop.mapreduce.RecordReader;
import org.apache.hadoop.mapreduce.TaskAttemptContext;

/** An {@link InputFormat} for {@link SequenceFile}s. */
@InterfaceAudience.Public
@InterfaceStability.Stable
public class SequenceFileInputFormat<K, V> extends FileInputFormat<K, V> {

    @Override
    public RecordReader<K, V> createRecordReader(InputSplit split, TaskAttemptContext context) throws IOException {
        return new SequenceFileRecordReader<K, V>();
    }

    @Override
    protected long getFormatMinSplitSize() {
        return SequenceFile.SYNC_INTERVAL;
    }

    @Override
    protected List<FileStatus> listStatus(JobContext job) throws IOException {

        List<FileStatus> files = super.listStatus(job);
        int len = files.size();
        for (int i = 0; i < len; ++i) {
            FileStatus file = files.get(i);
            if (file.isDirectory()) { // it's a MapFile
                Path p = file.getPath();
                FileSystem fs = p.getFileSystem(job.getConfiguration());
                // use the data file
                files.set(i, fs.getFileStatus(new Path(p, MapFile.DATA_FILE_NAME)));
            }
        }
        return files;
    }
}