Sound, Music, and Video: MMAPI - Beginning J2ME: From Novice to Professional - page 311

If you want to jump to a particular point in an audio clip, call setMediaTime() . You can find out
the current media time using getMediaTime() . The total time represented by the audio clip is
returned from getDuration() . For some types of streaming media, the duration cannot be
determined, in which case the special value TIME_UNKNOWN will be returned.
Players can also loop, which means the audio clip is played over and over again. You can
control this behavior by calling setLoopCount() before the Player is started. Pass a value of -1
to loop indefinitely.
Beyond the Player interface is a whole world of Controls . You can obtain a list of Controls
for a Player by calling getControls() (a method Player inherits from the Controllable interface).
This method returns an array of Controls that are appropriate for the Player . The ABB only
defines a VolumeControl and a ToneControl , but implementations are free to provide other
controls appropriate for the content types and protocols they support.
To obtain just one control, pass its name to Player 's getControl() method (again
inherited from Controllable ). The name is the name of an interface in the
javax.microedition.media.control package.
The Player must be in at least a REALIZED state to return its controls.
To use a VolumeControl to set playback volume to half its maximum, for example, you
would do something like this:
// Player player = Manager.createPlayer(...);
player.prefetch();
VolumeControl vc = (VolumeControl)player.getControl("VolumeControl");
vc.setLevel(50);
Listening for Player Events
Player includes methods for adding and removing listeners that will be notified about various
milestones in the Player 's life:
public void addPlayerListener(PlayerListener playerListener)
public void removePlayerListener(PlayerListener playerListener)
PlayerListener defines a single method that is called with a variety of informational messages:
public void playerUpdate(Player player, String event, Object eventData)
The player parameter, of course, is the Player generating the event. The event is described
by a string, event , and may include additional information, eventData . Constants in the
PlayerListener interface describe common events: STARTED , END_OF_MEDIA , and
VOLUME_CHANGED are a few. See the API documentation for the full list.
Tones and Tone Sequences
You've already seen how easy it is to play single tones using Manager . There's a somewhat more
sophisticated tone sequence player lurking in the MIDP 2.0 media APIs. It's implemented
within the Player and Control architecture, which is kind of a kluge, considering that tone
sequences have little in common with sampled audio.
To obtain the tone sequence Player , just pass a special value ( Manager 's
TONE_DEVICE_LOCATOR ) to createPlayer() . If you examine TONE_DEVICE_LOCATOR , you'll see it is