PostgreSQLCopyExportJob.java 文件源码

@Override
protected void configureMapper(Job job, String tableName,
    String tableClassName) throws ClassNotFoundException, IOException {
  if (isHCatJob) {
    throw new IOException("Sqoop-HCatalog Integration is not supported.");
  }
  switch (getInputFileType()) {
    case AVRO_DATA_FILE:
      throw new IOException("Avro data file is not supported.");
    case SEQUENCE_FILE:
    case UNKNOWN:
    default:
      job.setMapperClass(getMapperClass());
  }

  // Concurrent writes of the same records would be problematic.
  ConfigurationHelper.setJobMapSpeculativeExecution(job, false);
  job.setMapOutputKeyClass(NullWritable.class);
  job.setMapOutputValueClass(NullWritable.class);
}