How do I attach VisualVM to a simple Java process running in a Docker container

At first you should run you application with these JVM params:

-Dcom.sun.management.jmxremote
-Dcom.sun.management.jmxremote.port=9010
-Dcom.sun.management.jmxremote.local.only=false
-Dcom.sun.management.jmxremote.authenticate=false
-Dcom.sun.management.jmxremote.ssl=false

Then you should expose port for docker:

EXPOSE 9010

Also specify port binding with docker run command:

docker run -p 9010:9010 -it --rm --name hwd hello-world-daemon

After that you can connect with Jconsole to local 9010 port and manage application run in Docker.