code: protected void addCollectibleDocument(final BsonDocument document, final BsonOutput bsonOutput, final FieldNameValidator validator) {
          addDocument(document, getCodec(document), EncoderContext.builder().isEncodingCollectibleDocument(true).build(), bsonOutput,
                      validator, settings.getMaxDocumentSize(), null);
      }
docs: Appends a document to the message that is intended for storage in a collection.
  
  @param document the document
  @param bsonOutput the output
  @param validator the field name validator