content: /*
   * 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
   *
   *     https://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.mapreduce;
  
  import java.io.IOException;
  
  import org.apache.avro.Schema;
  import org.apache.avro.hadoop.io.AvroSequenceFile;
  import org.apache.hadoop.conf.Configuration;
  import org.apache.hadoop.fs.FileSystem;
  import org.apache.hadoop.fs.Path;
  import org.apache.hadoop.io.SequenceFile;
  import org.apache.hadoop.io.SequenceFile.CompressionType;
  import org.apache.hadoop.io.compress.CompressionCodec;
  import org.apache.hadoop.io.compress.DefaultCodec;
  import org.apache.hadoop.mapreduce.Job;
  import org.apache.hadoop.mapreduce.RecordWriter;
  import org.apache.hadoop.mapreduce.TaskAttemptContext;
  import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
  import org.apache.hadoop.util.ReflectionUtils;
  
  /**
   * A sequence file output format that knows how to write AvroKeys and AvroValues
   * in addition to Writables.
   *
   * @param <K> The job output key type (may be a Writable, AvroKey).
   * @param <V> The job output value type (may be a Writable, AvroValue).
   */
  public class AvroSequenceFileOutputFormat<K, V> extends FileOutputFormat<K, V> {
    /** {@inheritDoc} */
    @Override
    public RecordWriter<K, V> getRecordWriter(TaskAttemptContext context) throws IOException, InterruptedException {
      Configuration conf = context.getConfiguration();
  
      // Configure compression if requested.
      CompressionCodec codec = null;
      CompressionType compressionType = CompressionType.NONE;
      if (getCompressOutput(context)) {
        // Find the kind of compression to do.
        compressionType = getOutputCompressionType(conf);
  
        // Find the right codec.
        Class<?> codecClass = getOutputCompressorClass(context, DefaultCodec.class);
        codec = (CompressionCodec) ReflectionUtils.newInstance(codecClass, conf);
      }
  
      // Get the path of the output file.
      Path outputFile = getDefaultWorkFile(context, "");
      FileSystem fs = outputFile.getFileSystem(conf);
  
      // Configure the writer.
      AvroSequenceFile.Writer.Options options = new AvroSequenceFile.Writer.Options().withFileSystem(fs)
          .withConfiguration(conf).withOutputPath(outputFile).withKeyClass(context.getOutputKeyClass())
          .withValueClass(context.getOutputValueClass()).withProgressable(context).withCompressionType(compressionType)
          .withCompressionCodec(codec);
      Schema keySchema = AvroJob.getOutputKeySchema(conf);
      if (null != keySchema) {
        options.withKeySchema(keySchema);
      }
      Schema valueSchema = AvroJob.getOutputValueSchema(conf);
      if (null != valueSchema) {
        options.withValueSchema(valueSchema);
      }
      final SequenceFile.Writer out = AvroSequenceFile.createWriter(options);
  
      return new RecordWriter<K, V>() {
        @Override
        public void write(K key, V value) throws IOException {
          out.append(key, value);
        }
  
        @Override
        public void close(TaskAttemptContext context) throws IOException {
          out.close();
        }
      };
    }
  
    /**
     * Sets the type of compression for the output sequence file.
     *
     * @param job             The job configuration.
     * @param compressionType The compression type for the target sequence file.
     */
    public static void setOutputCompressionType(Job job, CompressionType compressionType) {
      setCompressOutput(job, true);
      job.getConfiguration().set(FileOutputFormat.COMPRESS_TYPE, compressionType.name());
    }
  
    /**
     * Gets type of compression for the output sequence file.
     *
     * @param conf The job configuration.
     * @return The compression type.
     */
    public static CompressionType getOutputCompressionType(Configuration conf) {
      String typeName = conf.get(FileOutputFormat.COMPRESS_TYPE);
      if (typeName != null) {
        return CompressionType.valueOf(typeName);
      }
      return SequenceFile.getDefaultCompressionType(conf);
    }
  }
  