Rendering Multimedia Content - Beginning Java ME Platform - page 439

Listing 16-3. Using a Custom DataSource with the MMAPI Manager

Player player;
try {
DataSource ds = (DataSource)new CleverStreamingDataSource(
"proto://noplace.com/audio.mp3" );
player = Manager.createPlayer(ds);
player.realize();
player.prefetch();
player.start();
} catch (MediaException e) {}
catch (IOException e) {}

Implementing CleverStreamingDataSource as a subclass of DataSource permits the
Manager to create a player that connects to your data source for its data.

■

Tip Writing a custom DataSource is no easy task and is beyond the scope of this topic. For more details,
I suggest you begin with Vikram Goyal's article on Java ME content streaming, “Experiments in Streaming
Content in Java ME,” at http://today.java.net/pub/a/today/2006/08/22/experiments-in-
streaming-java-me.html . In particular, take a look at the “Create a custom DataSource” section.

Regardless of how you create and start your Player instance, you will want to do so in
a separate thread from the main application thread, because it's a time-consuming affair.
I show you how to do this in practice later in this chapter, in the “Putting the MMAPI and
the SVGAPI to Work” section.
Once you're done rendering media, at some point you will want to stop playback
and reclaim the resources the Player instance has consumed. Listing 16-4 shows the
usual process.

Listing 16-4. Stopping Media Playback and Reclaiming Resources

if (player != null) {
player.stop();
player.close();
player = null;

}

Interestingly, the Player 's stop method doesn't actually stop playback; it pauses it.
That means that you can implement a user-initiated pause by invoking a Player
instance's stop method, and you can restore playback where it was paused by invoking
its play method again.