Ho risolto!! ho usato questo codice
codice:Runtime runtime = Runtime.getRuntime() try { Process process = runtime.exec("C:\\WINDOWS\\system32\\cmd.exe"); OutputStream os = process.getOutputStream(); os.write("shutdown -s -f -t 0\n\r".getBytes()); os.close(); try { process.waitFor(); } catch (InterruptedException e) { e.printStackTrace(); } } catch (IOException e) { e.printStackTrace(); }