[Chapter 14] 14.2 AudioClip Interface

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| Chapter 14 And Then There Were Applets |

## 14.2 AudioClip Interface

Once an audio file is loaded into memory with `getAudioClip()`, you use the `AudioClip` interface to work with it. Methods

Three methods define the `AudioClip` interface. The class that implements these methods depends on the run-time environment; the class is probably `sun.applet.AppletAudioClip` or `netscape.applet.AppletAudioClip`.

If you play an audio clip anywhere within your `Applet`, you should call the `AudioClip` `stop()` method within the `stop()` method of the applet. This ensures that the audio file will stop playing when the user leaves your web page. Stopping audio clips is a must if you call `loop()` to play the sound continuously; if you don't stop an audio clip, the user will have to exit the browser to get the sound to stop playing.

Applets can play audio clips simultaneously. Based upon the user's actions, you may want to play a sound file in the background continuously, while playing other files.

void play ()

  The `play()` method plays the audio clip once from the beginning.

void loop ()

  The `loop()` method plays the audio clip continuously. When it gets to the end-of-file marker, it resets itself to the beginning.

void stop ()

  The `stop()` method stops the applet from playing the audio clip.

### Using an AudioClip

The applet in Example 14.2 loads three audio files in the `init()` method. The `start()` method plays Dino barking in the background as a continuous loop. Whenever the browser calls `paint()`, Fred yells "Wilma," and when you click the mouse anywhere, the call to `mouseDown()` plays Fred yelling, "Yabba-Dabba-Doo." If you try real hard, all three can play at once. Before playing any audio clip, the applet makes sure that the clip is not null--that is, that the clip loaded correctly. `stop()` stops all clips from playing; you should make sure that applets stop all audio clips before the viewer leaves the web page.

#### Example 14.2: AudioClip Usage

    import java.net.*;
    import java.awt.*;
    import java.applet.*;
    public class AudioTestExample extends Applet{
        AudioClip audio1, audio2, audio3;
        public void init () {
            audio1 = getAudioClip (getCodeBase(), "audio/flintstones.au");
            audio2 = getAudioClip (getCodeBase(), "audio/dino.au");
            audio3 = getAudioClip (getCodeBase(), "audio/wilma.au");
        }
        public boolean mouseDown (Event e, int x, int y) {
            if (audio1 != null)
                audio1.play();
            return true;
        }
        public void start () {
            if (audio2 != null)
                audio2.loop();
        }
        public void paint (Graphics g) {
            if (audio3 != null)
                audio3.play();
        }
        public void stop () {
            if (audio1 != null)
                audio1.stop();
            if (audio2 != null)
                audio2.stop();
            if (audio3 != null)
                audio3.stop();
        }
    }

What's a Java Applet? |  | AppletContext Interface