public string[] GetInstalledJavas() {
        // hold the registry subkeys that list the installed JRE's
        string[] jres = null;
        try {
            RegistryKey myKey = Registry.LocalMachine;
            myKey = myKey.OpenSubKey(@"SOFTWAREJavaSoftJava Plug-in"); // read-only
            jres = myKey.GetSubKeyNames();
        } catch (Exception myException) {
            Console.Writeline(myException.ToString());
        }
        return jres;
}