private static List<String> getFieldNames( Iterable<Field> fields ) {
        return FluentIterable.from( ReflectionUtil.getAllFieldNames( fields ) )
            .transform( new Function<String, String>() {
                @Override
                public String apply( String input ) {
                    return input.replace( '_', ' ' );
                }
            } ).toList();
    }
{@link com.tngtech.jgiven.format.AnnotationArgumentFormatter} that is used by the {@link POJOFormat}
annotation
jgiven-core/src/main/java/com/tngtech/jgiven/format/POJOAnnotationFormatter.java