org.apache.hadoop.mapred.SequenceFileAsTextRecordReader.java Source code

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Here is the source code for org.apache.hadoop.mapred.SequenceFileAsTextRecordReader.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.mapred;

import java.io.IOException;

import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.classification.InterfaceStability;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.io.Writable;
import org.apache.hadoop.io.WritableComparable;

/**
 * This class converts the input keys and values to their String forms by calling toString()
 * method. This class to SequenceFileAsTextInputFormat class is as LineRecordReader
 * class to TextInputFormat class.
 */
@InterfaceAudience.Public
@InterfaceStability.Stable
public class SequenceFileAsTextRecordReader implements RecordReader<Text, Text> {

    private final SequenceFileRecordReader<WritableComparable, Writable> sequenceFileRecordReader;

    private WritableComparable innerKey;
    private Writable innerValue;

    public SequenceFileAsTextRecordReader(Configuration conf, FileSplit split) throws IOException {
        sequenceFileRecordReader = new SequenceFileRecordReader<WritableComparable, Writable>(conf, split);
        innerKey = sequenceFileRecordReader.createKey();
        innerValue = sequenceFileRecordReader.createValue();
    }

    public Text createKey() {
        return new Text();
    }

    public Text createValue() {
        return new Text();
    }

    /** Read key/value pair in a line. */
    public synchronized boolean next(Text key, Text value) throws IOException {
        Text tKey = key;
        Text tValue = value;
        if (!sequenceFileRecordReader.next(innerKey, innerValue)) {
            return false;
        }
        tKey.set(innerKey.toString());
        tValue.set(innerValue.toString());
        return true;
    }

    public float getProgress() throws IOException {
        return sequenceFileRecordReader.getProgress();
    }

    public synchronized long getPos() throws IOException {
        return sequenceFileRecordReader.getPos();
    }

    public synchronized void close() throws IOException {
        sequenceFileRecordReader.close();
    }

}