Sample Questions for the Final Exam

Answer the Sample Questions for the Mid-Term Exam .
Describe protection domains in J2ME. Make sure you discuss permission types and the role that is played by code signing.
Explain the difference between server authentication and client authentication.
Explain the difference between a (simple) file system and a record management system (as it is implemented in J2ME).

Complete the following getAllEmailAddresses() method. It must:

Return a Vector of String objects that contains the name and email address of all of the Contact objects in a ContactList that have a non-empty EMAIL field.
Check to see if all of the fields you use are supported by the PIM on the device.

public Vector getAllEmailAddresses()
{
  ContactList    contacts;
  Vector         result;

  try 
  {
    contacts = (ContactList) PIM.getInstance().openPIMList(PIM.CONTACT_LIST, 
                                                           PIM.READ_WRITE);



























   } 
   catch (PIMException e)
   {
    // An error occurred so return null
   }

   return result;
 }

}

Illustrate, using a UML statechart diagram, the way in which an explicit (non-orthogonal) persistant object store is normally used.
Write a MIDlet that:
1. Allows the user to enter the URL (of an HTML file on an HTTP server) in a TextField on a Form that looks something like the following:
2. Allows the user to initiate a download of the file at the given URL.
3. Downloads the HTML page (from the HTTP server specified in the URL).
4. Displays the downloaded file in a TextBox.
Modify your implementation of the Translator class from the Sample Questions for the Mid-Term Exam so that it uses a translation algorithm on another device (i.e., a translation server).
Describe three different approaches to mobile client-server computing [as, for example, in Jing et al. (1999)].
Describe (using whatever technique you think is most appropriate) the Bluetooth discovery process.