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.trevni.avro.mapreduce;
  
  import java.io.IOException;
  
  import org.apache.avro.Schema;
  import org.apache.avro.mapred.AvroKey;
  import org.apache.avro.mapreduce.AvroJob;
  import org.apache.hadoop.io.NullWritable;
  import org.apache.hadoop.mapreduce.TaskAttemptContext;
  
  /**
   * Writes Trevni records to an Trevni container file output stream.
   *
   * @param <T> The Java type of the Trevni data to write.
   */
  public class AvroTrevniKeyRecordWriter<T> extends AvroTrevniRecordWriterBase<AvroKey<T>, NullWritable, T> {
  
    /**
     * Constructor.
     * 
     * @param context The TaskAttempContext to supply the writer with information
     *                form the job configuration
     */
    public AvroTrevniKeyRecordWriter(TaskAttemptContext context) throws IOException {
      super(context);
    }
  
    /** {@inheritDoc} */
    @Override
    public void write(AvroKey<T> key, NullWritable value) throws IOException, InterruptedException {
      writer.write(key.datum());
      if (writer.sizeEstimate() >= blockSize) // block full
        flush();
    }
  
    /** {@inheritDoc} */
    @Override
    protected Schema initSchema(TaskAttemptContext context) {
      boolean isMapOnly = context.getNumReduceTasks() == 0;
      return isMapOnly ? AvroJob.getMapOutputKeySchema(context.getConfiguration())
          : AvroJob.getOutputKeySchema(context.getConfiguration());
    }
  }
  