import java.util.prefs.Preferences;
public class Main {
public static void main(String[] args) {
String PREF_KEY = "org.username";
// Write Preferences information to HKCU (HKEY_CURRENT_USER),HKCU\Software\JavaSoft\Prefs\
Preferences userPref = Preferences.userRoot();
userPref.put(PREF_KEY, "a");
System.out.println("Preferences = " + userPref.get(PREF_KEY, PREF_KEY + " was not found."));
// Write Preferences information to HKLM (HKEY_LOCAL_MACHINE),HKLM\Software\JavaSoft\Prefs\
Preferences systemPref = Preferences.systemRoot();
systemPref.put(PREF_KEY, "b");
System.out.println("Preferences = " + systemPref.get(PREF_KEY, PREF_KEY + " was not found."));
}
}