Question

The problem is that this is a JAAS login application. The below method uses Java’s Callback class and it’s kinda bugging me out. Because it is wired in with the Callback class (among other things) the standard

       JTextfield username = Class.getText(); 

isn’t working. Your thoughts are welcome:

     public boolean login() throws LoginException {

   // prompt for a user name and password
   if (callbackHandler == null)
       throw new LoginException("Error: no CallbackHandler available " +
        "to garner authentication information from the user");

   Callback[] callbacks = new Callback[2];
   callbacks[0] = new NameCallback("user name: ");
   callbacks[1] = new PasswordCallback("password: ", false);

   try {
       callbackHandler.handle(callbacks);
       username = ((NameCallback)callbacks[0]).getName();            


       char[] tmpPassword = ((PasswordCallback)callbacks[1]).getPassword();            


       if (tmpPassword == null) {
       // treat a NULL password as an empty password
       tmpPassword = new char[0];
       }
       password = new char[tmpPassword.length];
       System.arraycopy(tmpPassword, 0,
        password, 0, tmpPassword.length);
       ((PasswordCallback)callbacks[1]).clearPassword();

   } catch (java.io.IOException ioe) {
    throw new LoginException(ioe.toString());
   } catch (UnsupportedCallbackException uce) {
    throw new LoginException("Error: " + uce.getCallback().toString() +
    " not available to garner authentication information " +
    "from the user");
   }

       . . . 

Answer 1

Thanks to Hovercraft Full Of Eels pointing me in the right direction, I was able to figure it out. Below is the correct code in the my Callback handler (not my Login Module as I originally though above):

 public void handle(Callback[] callbacks)throws IOException, UnsupportedCallbackException 
 {
     for (int i = 0; i < callbacks.length; i++) 
     {
         if 
         {
             . . . .
         }
         else if (callbacks[i] instanceof NameCallback) 
         {

    // prompt the user for a username
    NameCallback nc = (NameCallback)callbacks[i];  
    System.err.print(nc.getPrompt());
    System.err.flush();
    nc.setName(Video_Game_Store.usrName.getText());

     } 
         else if (callbacks[i] instanceof PasswordCallback) 
         {

    // prompt the user for sensitive information
    PasswordCallback pc = (PasswordCallback)callbacks[i];
    System.err.print(pc.getPrompt());
    System.err.flush();         
            pc.setPassword(Video_Game_Store.psWord.getText().toCharArray());

     } 
         else 
         {
    throw new UnsupportedCallbackException
        (callbacks[i], "Unrecognized Callback");
     }
 }
 }