pig/src/main/java/com/twitter/elephantbird/pig/load/ProtobufPigLoader.java
@Override
  public Tuple getNext() throws IOException {
    if (tupleTemplate == null) {
      tupleTemplate = new ProjectedProtobufTupleFactory<M>(typeRef, requiredFieldList);
    }

    M value = getNextBinaryValue(typeRef);
    return value != null ?
        tupleTemplate.newTuple(value) : null;
  }
@Override
  public Tuple getNext() throws IOException {
    if (tupleTemplate == null) {
      tupleTemplate = new ProjectedProtobufTupleFactory<M>(typeRef, requiredFieldList);
    }

    M value = getNextBinaryValue(typeRef);
    return value != null ?
        tupleTemplate.newTuple(value) : null;
  }
Return every non-null line as a single-element tuple to Pig.
<p>
A small fraction of bad records in input are tolerated.
See  {@link LzoRecordReader} for more information on error handling.