private Path verifyHome(String homeGuess, String jiveConfigName) throws FileNotFoundException {
        final Path openfireHome = Paths.get(homeGuess);
        final Path configFile = openfireHome.resolve(jiveConfigName);
        if (!Files.exists(configFile)) {
            throw new FileNotFoundException();
        }
        else {
            try {
                return openfireHome.toAbsolutePath();
            }
            catch (Exception ex) {
                throw new FileNotFoundException();
            }
        }
    }
Verifies that the given home guess is a real Openfire home directory.
We do the verification by checking for the Openfire config file in
the config dir of jiveHome.

@param homeGuess a guess at the path to the home directory.
@param jiveConfigName the name of the config file to check.
@return a file pointing to the home directory or null if the
        home directory guess was wrong.
@throws java.io.FileNotFoundException if there was a problem with the home
                                      directory provided
xmppserver/src/main/java/org/jivesoftware/openfire/XMPPServer.java