Java Tutorial/J2ME/Audio Player
Содержание
Audio Player Demo
<source lang="java">
import javax.microedition.lcdui.rumand; import javax.microedition.lcdui.rumandListener; import javax.microedition.lcdui.Display; import javax.microedition.lcdui.Displayable; import javax.microedition.lcdui.Form; import javax.microedition.lcdui.Gauge; import javax.microedition.lcdui.Item; import javax.microedition.lcdui.ItemStateListener; import javax.microedition.lcdui.List; import javax.microedition.media.Manager; import javax.microedition.media.Player; import javax.microedition.media.control.VolumeControl; import javax.microedition.midlet.MIDlet; class AudioPlayerCanvas implements ItemStateListener {
private AudioPlayer parent;
private Form form = new Form("");
private Gauge gauge = new Gauge("Volume: 50", true, 100, 50);
private VolumeControl volume;
private Player player;
private boolean paused = false;
public AudioPlayerCanvas(AudioPlayer parent) {
this.parent = parent;
form.append(gauge);
form.addCommand(parent.exitCommand);
form.addCommand(parent.backCommand);
form.setCommandListener(parent);
form.setItemStateListener(this);
}
public void playMedia(String locator) {
try {
player = Manager.createPlayer(getClass().getResourceAsStream(locator), "audio/x-wav");
player.realize();
volume = (VolumeControl) player.getControl("VolumeControl");
volume.setLevel(50);
gauge.setValue(volume.getLevel());
gauge.setLabel("Volume: " + volume.getLevel());
player.setLoopCount(2);
player.start();
} catch (Exception e) {
e.printStackTrace();
}
}
public void pauseMedia() {
if (player != null) {
try {
player.stop();
paused = true;
} catch (Exception e) {
}
}
}
public void restartMedia() {
if (player != null) {
try {
player.start();
paused = false;
} catch (Exception e) {
}
}
}
public boolean isPlayerPaused() {
return paused;
}
public Form getForm() {
return this.form;
}
public void itemStateChanged(Item item) {
volume.setLevel(gauge.getValue());
gauge.setLabel("Volume: " + volume.getLevel());
}
public void cleanUp() {
if (player != null) {
player.close();
player = null;
}
}
} public class J2MEAudioPlayer extends MIDlet implements CommandListener {
private String[] audioDisplayList = { "y.wav", "e.wav", "r.wav" };
private String[] audioList = { "/y.wav", "/e.wav", "/r.wav" };
protected Display display;
private AudioPlayerCanvas canvas;
private List list = new List("Pick an Audio file", List.IMPLICIT, audioDisplayList, null);
protected Command exitCommand = new Command("Exit", Command.EXIT, 1);
protected Command backCommand= new Command("Back", Command.BACK, 1);
public J2MEAudioPlayer() {
list.addCommand(exitCommand);
list.setCommandListener(this);
canvas = new AudioPlayerCanvas(this);
display = Display.getDisplay(this);
}
public void startApp() {
if (canvas.isPlayerPaused()) {
canvas.restartMedia();
display.setCurrent(canvas.getForm());
} else {
display.setCurrent(list);
}
}
public void pauseApp() {
canvas.pauseMedia();
}
public void destroyApp(boolean unconditional) {
canvas.cleanUp();
}
public void commandAction(Command command, Displayable disp) {
if (command == exitCommand) {
canvas.cleanUp();
notifyDestroyed();
return;
} else if (command == backCommand) {
canvas.cleanUp();
display.setCurrent(list);
return;
}
if (disp == list) {
canvas.playMedia(audioList[list.getSelectedIndex()]);
display.setCurrent(canvas.getForm());
}
}
}</source>
Cached Audio Player
<source lang="java">
import java.util.Enumeration; import java.util.Hashtable; import javax.microedition.lcdui.rumand; import javax.microedition.lcdui.rumandListener; import javax.microedition.lcdui.Display; import javax.microedition.lcdui.Displayable; import javax.microedition.lcdui.Form; import javax.microedition.lcdui.Gauge; import javax.microedition.lcdui.Item; import javax.microedition.lcdui.ItemStateListener; import javax.microedition.lcdui.List; import javax.microedition.media.Manager; import javax.microedition.media.Player; import javax.microedition.media.control.VolumeControl; import javax.microedition.midlet.MIDlet; class CachedAudioPlayerCanvas implements ItemStateListener {
private CachingAudioPlayer parent;
private Form form = new Form("");
private Gauge gauge = new Gauge("Volume: 50", true, 100, 50);
private VolumeControl volume;
private Player player;
private boolean paused = false;
private Hashtable players = new Hashtable();
public CachedAudioPlayerCanvas(CachingAudioPlayer parent) {
this.parent = parent;
form.append(gauge);
form.addCommand(parent.exitCommand);
form.addCommand(parent.backCommand);
form.setCommandListener(parent);
form.setItemStateListener(this);
}
public void playMedia(String locator) {
try {
player = (Player) players.get(locator);
if (player == null) {
player = Manager.createPlayer(getClass().getResourceAsStream(locator), "audio/x-wav");
player.prefetch();
players.put(locator, player);
}
volume = (VolumeControl) player.getControl("VolumeControl");
volume.setLevel(50);
gauge.setValue(volume.getLevel());
gauge.setLabel("Volume: " + volume.getLevel());
player.setLoopCount(2);
player.start();
form.setTitle("Playing " + locator);
} catch (Exception e) {
e.printStackTrace();
}
}
public void pauseMedia() {
if (player != null) {
try {
player.stop();
paused = true;
} catch (Exception e) {
}
}
}
public void restartMedia() {
if (player != null) {
try {
player.start();
paused = false;
} catch (Exception e) {
}
}
}
public boolean isPlayerPaused() {
return paused;
}
public Form getForm() {
return this.form;
}
public void itemStateChanged(Item item) {
volume.setLevel(gauge.getValue());
gauge.setLabel("Volume: " + volume.getLevel());
}
public void cleanUp() {
if (player != null) {
try {
player.setMediaTime(0);
} catch (Exception e) {
}
player.deallocate();
player = null;
}
}
public void closeAll() {
for (Enumeration e = players.elements(); e.hasMoreElements();) {
Player p = (Player) e.nextElement();
p.close();
}
}
} public class J2MECachingAudioPlayer extends MIDlet implements CommandListener {
private String[] audioDisplayList = { "B", "A", "L" };
private String[] audioList = { "/b.wav", "/a.wav", "/l.wav" };
protected Display display;
private CachedAudioPlayerCanvas canvas;
private List list = new List("Pick an Audio file", List.IMPLICIT, audioDisplayList, null);
protected Command exitCommand = new Command("Exit", Command.EXIT, 1);
protected Command backCommand = new Command("Back", Command.BACK, 1);
public J2MECachingAudioPlayer() {
list.addCommand(exitCommand);
list.setCommandListener(this);
canvas = new CachedAudioPlayerCanvas(this);
display = Display.getDisplay(this);
}
public void startApp() {
if (canvas.isPlayerPaused()) {
canvas.restartMedia();
display.setCurrent(canvas.getForm());
} else {
display.setCurrent(list);
}
}
public void pauseApp() {
canvas.pauseMedia();
}
public void destroyApp(boolean unconditional) {
canvas.closeAll();
}
public void commandAction(Command command, Displayable disp) {
if (command == exitCommand) {
canvas.closeAll();
notifyDestroyed();
return;
} else if (command == backCommand) {
canvas.cleanUp();
display.setCurrent(list);
return;
}
}
}</source>
implements PlayerListener
<source lang="java">
import javax.microedition.lcdui.StringItem; import javax.microedition.media.Player; import javax.microedition.media.PlayerListener; import javax.microedition.media.control.VolumeControl; public class EventHandler implements PlayerListener {
private StringItem item;
public EventHandler(StringItem item) {
this.item = item;
}
public void playerUpdate(Player player, String event, Object eventData) {
if (event == (PlayerListener.VOLUME_CHANGED)) {
VolumeControl vc = (VolumeControl) eventData;
updateDisplay("Volume Changed to: " + vc.getLevel());
if (vc.getLevel() > 60) {
updateDisplay("Volume higher than 60 is too loud");
vc.setLevel(60);
}
} else if (event == (PlayerListener.STOPPED)) {
updateDisplay("Player paused at: " + (Long) eventData);
} else if (event == (PlayerListener.STARTED)) {
updateDisplay("Player started at: " + (Long) eventData);
} else if (event == (PlayerListener.END_OF_MEDIA)) {
updateDisplay("Player reached end of loop.");
} else if (event == (PlayerListener.CLOSED)) {
updateDisplay("Player closed.");
} else if (event == (PlayerListener.ERROR)) {
updateDisplay("Error Message: " + (String) eventData);
}
}
public void updateDisplay(String text) {
item.setText(text);
System.err.println(text);
}
}</source>
Load WAV file from a web site
<source lang="java">
import javax.microedition.lcdui.rumand; import javax.microedition.lcdui.rumandListener; import javax.microedition.lcdui.Display; import javax.microedition.lcdui.Displayable; import javax.microedition.lcdui.List; import javax.microedition.lcdui.StringItem; import javax.microedition.media.Manager; import javax.microedition.media.Player; import javax.microedition.midlet.MIDlet; public class J2MENetworkTest extends MIDlet implements CommandListener {
private List list = new List("Press Play", List.IMPLICIT);
private Display display;
public J2MENetworkTest() {
list.addCommand(new Command("Exit", Command.EXIT, 1));
list.addCommand(new Command("Play", Command.SCREEN, 1));
list.setCommandListener(this);
display = Display.getDisplay(this);
}
public void startApp() {
display.setCurrent(list);
}
public void pauseApp() {
}
public void destroyApp(boolean unconditional) {
}
public void commandAction(Command cmd, Displayable disp) {
if (cmd.getLabel().equals("Exit")) {
notifyDestroyed();
} else {
try {
Player player = Manager.createPlayer("http://www.yoursite.ru/s.wav");
player.start();
} catch (Exception e) {
System.err.println(e);
}
}
}
}</source>
Network Player Manager
<source lang="java">
import javax.microedition.lcdui.rumand; import javax.microedition.lcdui.rumandListener; import javax.microedition.lcdui.Display; import javax.microedition.lcdui.Displayable; import javax.microedition.lcdui.Form; import javax.microedition.lcdui.List; import javax.microedition.lcdui.StringItem; import javax.microedition.media.Manager; import javax.microedition.media.Player; import javax.microedition.midlet.MIDlet; class ThreadedMIDlet extends MIDlet implements CommandListener {
private List list = new List("Press Play", List.IMPLICIT);
private Display display;
private NetworkPlayerManager mgr;
private Command cancel = new Command("Cancel", Command.CANCEL, 1);
public ThreadedMIDlet() {
list.addCommand(new Command("Exit", Command.EXIT, 1));
list.addCommand(new Command("Play", Command.SCREEN, 1));
list.setCommandListener(this);
display = Display.getDisplay(this);
}
public void startApp() {
display.setCurrent(list);
}
public void pauseApp() {
}
public void destroyApp(boolean unconditional) {
}
public void commandAction(Command cmd, Displayable disp) {
if (cmd.getLabel().equals("Exit")) {
notifyDestroyed();
} else if (cmd.getLabel().equals("Cancel")) {
mgr.cancel();
display.setCurrent(list);
} else {
try {
mgr = new NetworkPlayerManager(display, cancel, this);
Thread runner = new Thread(mgr);
runner.start();
} catch (Exception e) {
System.err.println(e);
}
}
}
} public class NetworkPlayerManager implements Runnable {
private Display display;
private Form form = new Form("Network Player Manager");
private StringItem msg = new StringItem("Please Wait ... ", null);
private boolean cancel = false;
private Player player = null;
public NetworkPlayerManager(Display display, Command cancelCmd, ThreadedMIDlet parent) {
this.display = display;
form.append(msg);
form.addCommand(cancelCmd);
form.setCommandListener(parent);
}
public void run() {
display.setCurrent(form);
boolean connected = false;
try {
player = Manager.createPlayer("http://www.yoursite.ru/s.wav");
player.realize();
connected = true;
} catch (Exception e) {
msg.setText("Failed: " + e.getMessage());
System.err.println(e);
return;
}
if (connected && !cancel)
msg.setText("Connected. Starting playback...");
else {
msg.setText("Unable to connect.");
return;
}
try {
player.start();
} catch (Exception pe) {
msg.setText(pe.getMessage());
}
}
public void cancel() {
cancel = true;
if (player != null)
player.deallocate();
}
}</source>
Player Event
<source lang="java">
import javax.microedition.lcdui.Display; import javax.microedition.lcdui.Form; import javax.microedition.lcdui.StringItem; import javax.microedition.media.Manager; import javax.microedition.media.Player; import javax.microedition.media.PlayerListener; import javax.microedition.midlet.MIDlet; public class EchoEventsMIDlet extends MIDlet implements PlayerListener {
private StringItem stringItem = new StringItem("", null);
public void startApp() {
try {
Form form = new Form("Player State");
form.append(stringItem);
Display.getDisplay(this).setCurrent(form);
Player player = Manager.createPlayer(getClass().getResourceAsStream("/b.wav"), "audio/x-wav");
player.addPlayerListener(this);
player.start();
} catch (Exception e) {
e.printStackTrace();
}
}
public void pauseApp() {
}
public void destroyApp(boolean unconditional) {
}
public void playerUpdate(Player player, String event, Object eventData) {
stringItem.setText(event);
System.err.println(event);
}
}</source>
Wav file player
<source lang="java">
import javax.microedition.media.Manager; import javax.microedition.media.Player; import javax.microedition.midlet.MIDlet; public class J2MESimplePlayer extends MIDlet {
public void startApp() {
try {
Player player = Manager.createPlayer(getClass().getResourceAsStream("/b.wav"), "audio/x-wav");
player.start();
} catch (Exception e) {
e.printStackTrace();
}
}
public void pauseApp() {
}
public void destroyApp(boolean unconditional) {
}
}</source>
