public static DnsTextEndpointGroupBuilder builder(String hostname,
                                                      Function<byte[], @Nullable Endpoint> mapping) {
        return new DnsTextEndpointGroupBuilder(hostname, mapping);
    }
Returns a new {@link DnsTextEndpointGroupBuilder} with
the specified hostname and {@link Function} mapping.

@param hostname the hostname to query DNS queries for
@param mapping the {@link Function} that maps the content of a {@code TXT} record into
               an {@link Endpoint}. The {@link Function} is expected to return {@code null}
               if the record contains unsupported content.
core/src/main/java/com/linecorp/armeria/client/endpoint/dns/DnsTextEndpointGroup.java