How can I gather and send metrics from java application to Prometheus without micrometer?

I have 2 things:

1. A java application.
2. Prometheus server

My task is gather application metrics and send then to Prometheus.

I've found only 1 way to do it: using Micrometer. And as a java application it is convenient to take spring boot because it has a good integration with Micrometer and latter has adapter for Prometheus.

Are there any other options ?

P.S. I try to achieve it via dropwizard metrics but I am stuck - there almost no information in google about it.