Playing Audio in Applet

AUDIO.md

Playing Audio in Applet

28th January 2019 , 🖋 Arjun Adhikari

An applet can play an audio file represented by the AudioClip interface in the java.applet package. The AudioClip interface has three methods, including :
public void play() − Plays the audio clip one time, from the beginning.
public void loop() − Causes the audio clip to replay continually.
public void stop() − Stops playing the audio clip.
To obtain an AudioClip object, you must invoke the getAudioClip() method of the Applet class. The getAudioClip() method returns immediately, whether or not the URL resolves to an actual audio file. The audio file is not downloaded until an attempt is made to play the audio clip.

Make sure you have file named sample.wav in the working directory :

PlayAudio.java

import java.awt.*;
import java.net.*; // For URL objects
import java.applet.*;

/*
	<applet code = "PlayAudio" height = "400" width = "400">
		<param name = "audioURL" value = "sample.wav">
	</applet>

*/

// AppletContext is an environment (interface) which helps to communicate with outer-environment and deal with media files such as audio, image.

public class PlayAudio extends Applet {
	public AudioClip myMusic; // Defining a variable of data type AudioClip.
	public AppletContext context;

	public void init() {
		context = this.getAppletContext();
		String audioURL = this.getParameter("audioURL"); // This gets the parameter passed from applet.
		if (audioURL == null) {
			audioURL = "sample.wav"; // If no parameter is passed.
		}

		try {
			URL myURL = new URL(this.getDocumentBase(), audioURL); // New URL object storing audio URL passed by user.
			myMusic = context.getAudioClip(myURL);
			// myMusic = this.getAudioClip(myURL); // Also can be done like this.
		} catch (MalformedURLException exc) {
			exc.printStackTrace();
			context.showStatus("Couldn't load audio file."); // Showing status to the Browser status bar.
		}
	}

	public void start() { // When Applet starts
		if (myMusic != null) {
			myMusic.loop();
		}
	}

	public void stop() { // When Applet stop
		if (myMusic != null) {
			myMusic.stop();
		}
	}
}