@Override
    public HttpFileBuilder entityTag(boolean enabled) {
        return (HttpFileBuilder) super.entityTag(enabled);
    }
Returns a newly created {@link HttpFile} with the properties configured so far. If this builder was
created with {@link HttpFile#builder(HttpData)} or {@link HttpFile#builder(HttpData, long)},
the returned instance will always be an {@link AggregatedHttpFile}.
core/src/main/java/com/linecorp/armeria/server/file/HttpFileBuilder.java