Events in a SIM toolkit applet

Question

Hi,
I am looking at some sample (and simple) code:
public MyApplet() {
          // Define the applet Menu Entry
          idMenu1 = reg.initMenuEntry(Menu1, (short) 0, (short) Menu1.length,
                    PRO_CMD_SELECT_ITEM, false, (byte) 0, (short) 0);
          // Define the Unformatted SMS PP event that trigger the applet
          reg.setEvent(EVENT_UNFORMATTED_SMS_PP_ENV);
public void processToolkit(byte event) {
          EnvelopeHandler envHdlr = EnvelopeHandler.getTheHandler();          
          if (event == EVENT_MENU_SELECTION) {
               byte selectedItemId = envHdlr.getItemIdentifier();
               if (selectedItemId == idMenu1) {
                    menu1Action();
          if (event == EVENT_UNFORMATTED_SMS_PP_ENV) {
               UnformattedSmsPpAction();
In processToolkit we procees EVENT_MENU_SELECTION and EVENT_UNFORMATTED_SMS_PP_ENV, yet in the ctor we subscribed only for the latter. Does that mean that it is not necessary to subscribe to EVENT_MENU_SELECTION and that this event is always delivered to the applet (that created the menu)?

Answer 1

For UICC, SIM etc check this link: [http://en.wikipedia.org/wiki/UICC]
For ETSI, 3GPP etc., this is where it gets confusing, you should do the research for yourself. As for using the latest specification, you actually want to use the specification your card complies to, i.e. if the card is old it may not comply with the latest specifications.
Regarding Java applets and toolkit applets:
To send commands to a Java applet you first select (see GlobalPlatform standard) it and then you send it some APDUs as specified in the 7816-4 and GlobalPlatform standards. You can also implement custom APDUs that only your applet will recognize.
The toolkit applets are Java applets, you can send them APDUs (first you select them) as well. The difference is that toolkit applets can also receive events from the mobile phone like SMS received or user selected some menu. You can also send commands to the phone to display text, menus etc.
A Java applet can do what a toolkit applet does, but to implement it yourself you be very hard. The Java API that is used in toolkit applet programming provides facilities to (for example) show something on the phone's display without sending and receiving heaps of APDUs.
If your card will be used in a mobile phone then you write a toolkit applet (to which you can still send APDUs if you have to). If your card will be used for something else, like access card or a bank card then you don't need toolkit applet functionality.
The biggest problem with this technology that there are almost no books, only the standards, which you do have to read, and forums.