A DESCRIPTION OF THE REQUEST :
I'm sorry if this is not the right mechanism for doing this but I can't find another means.

Within our product (BiglyBT) we have been making use of the DNS SPI for various reasons (proxing of certain DNS requests; triggering of the installation of software to handle various proxied domains). 

We need to be able to intercept DNS resolution requests and then either handle them ourselves or forward them to the default provider. From Java 9 we have been using reflection to access java.net.InetAddressImpl for delegation but this is obviously not optimal and also generates an 'illegal reflective access' warning with threats about future prohibition.

A feature we also want to implement, but are wary of doing so given the current support, is use of services such as DNS-over-HTTPS provided by Cloudflare (https://developers.cloudflare.com/1.1.1.1/dns-over-https/) via a DNS proxy.

We are very interested in having a standard way of achieving our aims here!

JUSTIFICATION :
Please see above