private String getFieldTypeFromMapping(final String fieldName, final FieldMapping fieldMeta) {
        final Optional<Property> firstFieldMapping = fieldMeta.mapping().values().stream().findFirst();

        if (firstFieldMapping.isPresent()) {
            return firstFieldMapping.get()._kind().jsonValue();
        } else {
            LOGGER.debug(() -> "Mapping properties for field '" + fieldName +
                               "' were in an unrecognised format. Field ignored.");
        }

        return null;
    }
Returns an `AbstractField` instance, based on the field's data type
stroom-search/stroom-search-elastic/src/main/java/stroom/search/elastic/search/ElasticSearchProvider.java