pig/src/main/java/com/twitter/elephantbird/pig/load/LzoBaseLoadFunc.java
protected RequiredFieldResponse pushProjectionHelper(
                                          RequiredFieldList requiredFieldList)
                                          throws FrontendException {
    try {
      getUDFProperties().setProperty(projectionKey,
                                     ObjectSerializer.serialize(requiredFieldList));
    } catch (IOException e) { // not expected
      throw new FrontendException(e);
    }

    return new RequiredFieldResponse(true);
  }
protected RequiredFieldResponse pushProjectionHelper(
                                          RequiredFieldList requiredFieldList)
                                          throws FrontendException {
    try {
      getUDFProperties().setProperty(projectionKey,
                                     ObjectSerializer.serialize(requiredFieldList));
    } catch (IOException e) { // not expected
      throw new FrontendException(e);
    }

    return new RequiredFieldResponse(true);
  }
A helper method for implementing
{@link LoadPushDown#pushProjection(RequiredFieldList)}. <p>

Stores requiredFieldList in context. The requiredFields are read from
context on the backend (in side {@link #setLocation(String, Job)}).