The jmc man page still shows the old URL for JMC user guide: http://docs.oracle.com/javase/8/docs/technotes/guides/jmc/index.html
With the introduction of the new javacomponents directory, that link should change to: http://docs.oracle.com/javacomponents/jmc.htm

The user can then choose the appropriate version of the guide from that tab.

Note: There is currently a redirect in place, but the link should be updated nonetheless.