When rmid is run without an appropriate security policy its says: (English version)

Activation.main: warning: sun.rmi.activation.execPolicy system
        property unspecified and no ExecPermissions/ExecOptionPermissions
        granted; subsequent activation attempts may fail due to unsuccessful
ExecPermission/ExecOptionPermission permission checks. For
documentation on how to configure rmid security, refer to:

        http://java.sun.com/j2se/1.4/docs/tooldocs/solaris/rmid.html
        http://java.sun.com/j2se/1.4/docs/tooldocs/win32/rmid.html

The URLs are no longer correct and need to be updated.

A more recent URL that seems similar is:
   http://docs.oracle.com/javase/7/docs/technotes/tools/solaris/rmid.html

But it is not present in the javase/8/docs

The message with the url appears to be present in the jdk/src/share/classes/sun/rmi/server/resource/rmid_*.properties files.