Goha wrote on 06.11.2007 22:44:

The JVM is started with the command "java".
It is stopped by stopping the application started within the JVM

This is a simplified version of the specification:

http://java.sun.com/docs/books/jls/second_edition/html/execution.doc.html#44411

starting and restarting is easy. Just use java.exe. See
http://mindprod.com/jgloss/javaexe.html

Stopping requires the app to notice and shut down.  One simple way is
to copy in a "pleasestop.dat" file into a directory.  The app
periodically checks for its existence. If it finds it, it deletes it
and shuts down gracefully.

You can also do it my sending a packet or message on a socket.

You also might do it with some platform specific trigger you catch in
C++ then pass on to Java via JNI.