org.apache.sqoop.mapreduce.AvroOutputFormat.java Source code

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Here is the source code for org.apache.sqoop.mapreduce.AvroOutputFormat.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.sqoop.mapreduce;

import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.net.URLDecoder;
import java.util.Map;

import org.apache.avro.Schema;
import org.apache.avro.file.CodecFactory;
import org.apache.avro.file.DataFileWriter;
import org.apache.avro.mapred.AvroWrapper;
import org.apache.avro.reflect.ReflectDatumWriter;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.NullWritable;
import org.apache.hadoop.mapreduce.RecordWriter;
import org.apache.hadoop.mapreduce.TaskAttemptContext;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;

import static org.apache.avro.file.DataFileConstants.DEFAULT_SYNC_INTERVAL;
import static org.apache.avro.file.DataFileConstants.DEFLATE_CODEC;
import static org.apache.avro.mapred.AvroOutputFormat.DEFAULT_DEFLATE_LEVEL;
import static org.apache.avro.mapred.AvroOutputFormat.DEFLATE_LEVEL_KEY;
import static org.apache.avro.mapred.AvroOutputFormat.EXT;
import static org.apache.avro.mapred.AvroOutputFormat.SYNC_INTERVAL_KEY;

/**
 * An {@link org.apache.hadoop.mapred.OutputFormat} for Avro data files.
 * <p/>
 * Note: This class is copied from the Avro project in version 1.5.4 and
 * adapted here to work with the "new" MapReduce API that's required in Sqoop.
 */
public class AvroOutputFormat<T> extends FileOutputFormat<AvroWrapper<T>, NullWritable> {

    static <T> void configureDataFileWriter(DataFileWriter<T> writer, TaskAttemptContext context)
            throws UnsupportedEncodingException {
        if (FileOutputFormat.getCompressOutput(context)) {
            int level = context.getConfiguration().getInt(DEFLATE_LEVEL_KEY, DEFAULT_DEFLATE_LEVEL);
            String codecName = context.getConfiguration().get(org.apache.avro.mapred.AvroJob.OUTPUT_CODEC,
                    DEFLATE_CODEC);
            CodecFactory factory = codecName.equals(DEFLATE_CODEC) ? CodecFactory.deflateCodec(level)
                    : CodecFactory.fromString(codecName);
            writer.setCodec(factory);
        }

        writer.setSyncInterval(context.getConfiguration().getInt(SYNC_INTERVAL_KEY, DEFAULT_SYNC_INTERVAL));

        // copy metadata from job
        for (Map.Entry<String, String> e : context.getConfiguration()) {
            if (e.getKey().startsWith(org.apache.avro.mapred.AvroJob.TEXT_PREFIX)) {
                writer.setMeta(e.getKey().substring(org.apache.avro.mapred.AvroJob.TEXT_PREFIX.length()),
                        e.getValue());
            }
            if (e.getKey().startsWith(org.apache.avro.mapred.AvroJob.BINARY_PREFIX)) {
                writer.setMeta(e.getKey().substring(org.apache.avro.mapred.AvroJob.BINARY_PREFIX.length()),
                        URLDecoder.decode(e.getValue(), "ISO-8859-1").getBytes("ISO-8859-1"));
            }
        }
    }

    @Override
    public RecordWriter<AvroWrapper<T>, NullWritable> getRecordWriter(TaskAttemptContext context)
            throws IOException, InterruptedException {

        boolean isMapOnly = context.getNumReduceTasks() == 0;
        Schema schema = isMapOnly ? AvroJob.getMapOutputSchema(context.getConfiguration())
                : AvroJob.getOutputSchema(context.getConfiguration());

        final DataFileWriter<T> WRITER = new DataFileWriter<T>(new ReflectDatumWriter<T>());

        configureDataFileWriter(WRITER, context);

        Path path = getDefaultWorkFile(context, EXT);
        WRITER.create(schema, path.getFileSystem(context.getConfiguration()).create(path));

        return new RecordWriter<AvroWrapper<T>, NullWritable>() {
            @Override
            public void write(AvroWrapper<T> wrapper, NullWritable ignore) throws IOException {
                WRITER.append(wrapper.datum());
            }

            @Override
            public void close(TaskAttemptContext taskAttemptContext) throws IOException, InterruptedException {
                WRITER.close();
            }
        };
    }

}