AvroEnumerator.java

public class AvroEnumerator implements Enumerator<Object> {

  private List<GenericData.Record> records;
  private Integer[] fields;
  private int pos;

  public AvroEnumerator(List<GenericData.Record> records, Integer[] fields) {
    this.records = records;
    this.fields = fields;
    this.pos = -1;
  }

  @Override
  public Object current() {
    GenericData.Record record = records.get(this.pos);
    return Arrays.stream(this.fields)
             .map(record::get).collect(Collectors.toList()).toArray();
  }

  @Override
  public boolean moveNext() {
    return (this.records.size() > (++this.pos));
  }

  @Override
  public void reset() {
    this.pos = -1;
  }

  @Override
  public void close() {}
}