Categories: Java | Java ME | How To | Code Examples | Multimedia | Audio

This page was last modified 14:54, 5 December 2007.

From Forum Nokia Wiki

The method below shows how an mp3 file can be played from a server in Java ME.

public void playAudio()
{
  try
  {
    String url = "http://server/audio.mp3";
    HttpConnection conn = (HttpConnection)Connector.open(url, 
      Connector.READ_WRITE);
    InputStream is = conn.openInputStream();
    player = Manager.createPlayer(is,"audio/amr");
 
    player.realize();
    // get volume control for player and set volume to max
    vc = (VolumeControl) player.getControl("VolumeControl");
    if(vc != null)
    {
      vc.setLevel(100);
    }
    player.prefetch();
    player.start();
  }
  catch(Exception e)
  {}
}
</code java>
 
Note for S40 Devices: 
- The Midlet is responsible to avoid/catch out_of_memory exceptions in case the mp3 file
 to be downloaded exceeds the amount of free memory.
- A good practice to avoid these kind of problems may be to either:
  - add the keyword <progressive_download: enable> as an attribute to the midlets jad or manifest file
  or
  - change the url for the file to be downloaded to the format: 
resource://my_media_file.mp3?streamable=true 
In the case above this means: 
String url = "http://server/audio.mp3?streamable=true";
 
Applying one of the changes should result in streaming instead of first downloading 
the whole file and starting to play not before the complete file was downloaded.