Oracle Java Mobile Edition 1 Mobile Application Developer Certified Professional Sample Questions:

1. Given:
1 4. Canvas canvas;
1 5. // ...
2 4. canvas.repaint(10,10,20,20);
2 5. canvas.serviceRepaints();
What occurs when serviceRepaints() is called?

A) The application blocks until the paint() method returns.
B) The application blocks until the repaint() method returns.
C) The application immediately calls the paint() method.
D) The application immediately calls the repaint() method.

2. A JTWI device has a working socket implementation. A MIDlet requests permission to use socket connections on this device using the attribute MIDlet-Permissions-Opt, but is denied permission.
Given:
2 0. public void connect() {
2 1. try {
2 2. String addr = "socket://host.com:79";
2 3. SocketConnection sc;
2 4. sc = (SocketConnection) Connector.open(addr);
2 5. sc.setSocketOption(SocketConnection.LINGER, 5);
2 6. InputStream is = sc.openInputStream();
2 7. OutputStream os = sc.openOutputStream();
2 8. os.write("\\r\\n".getBytes());
2 9. int ch = is.read();
3 0. // ...
3 5. } catch (IOException ioe) {
3 6. // ...
4 0. }
4 1. }
Which is true assuming that the argument to Connector.open() points to a valid destination, and the device has resources to create new socket connections?

A) If connect() executes, a SecurityException is thrown at runtime at line 26.
B) The device disallows the MIDlet to be installed.
C) If connect() executes, a ConnectionNotFoundException is thrown at runtime at line 24.
D) If connect() executes, a SecurityException is thrown at runtime at line 24.
E) If connect() executes, a SecurityException is thrown at runtime at line 28.

3. Given the MIDlet code:
1 2. File f = new File("myFile.txt");
1 3. FileOutputStream ds = new FileOutputStream(f);
1 4. OutputStreamWriter os = new OutputStreamWriter(ds);
1 5. BufferedWriter buf = new BufferedWriter(os);
1 6. buf.write('c');
What is the result?

A) The code compiles and runs, but line 16 is ignored.
B) Compilation fails because the code uses one or more classes, which are not supported in CLDC 1.1.
C) Compilation succeeds, but an exception is thrown at runtime.
D) The code compiles and runs, and then writes the character c to the file myFile.txt.

4. A MIDlet suite is signed using X.509 PKI. Which encoding format must be used for the certificate entries in the JAD file?

A) base64
B) none
C) binary
D) yEnc

5. Given:
4 0. String outputString;
4 1. try {
4 2. Player p;
4 3. p = Manager.createPlayer("http://sun.com/barfoo.media");
4 4. p.setMediaTime(8000);
4 5. p.start();
4 6. outputString = "Playing!";
4 7. } catch (MediaException me) {
4 8. outputString = "Media Exception!";
4 9. } catch (IOException ioe) {
5 0. outputString = "IO Exception!";
5 1. }
Which is the result if the device does NOT support setting the media time on p?

A) outputString is set to "Playing!" with media playing from the beginning.
B) outputString is set to "IO Exception!" and the media is NOT played.
C) outputString is set to "Media Exception!" and the media is NOT played.
D) outputString is set to "Playing!" but the media is NOT played.

Solutions: