basic-lib/src/main/java/com/streamsets/pipeline/stage/origin/http/HttpClientSource.java
String parseHeadersOnly(BatchMaker batchMaker) throws StageException {
    HttpSourceOffset sourceOffset = new HttpSourceOffset(
            getResolvedUrl(),
            currentParameterHash,
            System.currentTimeMillis(),
            getCurrentPage()
    );

    Record record = getContext().createRecord(sourceOffset + "::0");
    addResponseHeaders(record.getHeader());
    record.set(Field.create(new HashMap()));

    batchMaker.addRecord(record);
    recordCount++;
    incrementSourceOffset(sourceOffset, 1);
    lastRequestCompletedTime = System.currentTimeMillis();
    return sourceOffset.toString();

  }
String parseHeadersOnly(BatchMaker batchMaker) throws StageException {
    HttpSourceOffset sourceOffset = new HttpSourceOffset(
            getResolvedUrl(),
            currentParameterHash,
            System.currentTimeMillis(),
            getCurrentPage()
    );

    Record record = getContext().createRecord(sourceOffset + "::0");
    addResponseHeaders(record.getHeader());
    record.set(Field.create(new HashMap()));

    batchMaker.addRecord(record);
    recordCount++;
    incrementSourceOffset(sourceOffset, 1);
    lastRequestCompletedTime = System.currentTimeMillis();
    return sourceOffset.toString();

  }
Used only for HEAD requests.  Sets up a record for output based on headers only
with an empty body.

@param batchMaker batch to add records to.
@return the next source offset to commit
@throws StageException if an unhandled error is encountered