Question

java大神求解啊，如何用java编写一个音乐播放器，然后播放器里面的歌可以顺序播放的。

Answer 1

参考代码如下
首先下载播放mp3的包，比如mp3spi1.9.4.jar。在工程中添加这个包。
播放器演示代码如下
package com.test.audio;
import java.io.File;
import java.awt.BorderLayout;
import java.awt.FileDialog;
import java.awt.Frame;
import java.awt.GridLayout;
import java.awt.Label;
import java.awt.List;
import java.awt.Menu;
import java.awt.MenuBar;
import java.awt.MenuItem;
import java.awt.MenuShortcut;
import java.awt.Panel;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;

import javax.sound.sampled.AudioFormat;
import javax.sound.sampled.AudioInputStream;
import javax.sound.sampled.AudioSystem;
import javax.sound.sampled.DataLine;
import javax.sound.sampled.SourceDataLine;

public class MusicPlayer extends Frame {
/**
*
*/
private static final long serialVersionUID = -2605658046194599045L;
boolean isStop = true;// 控制播放线程
boolean hasStop = true;// 播放线程状态

String filepath;// 播放文件目录
String filename;// 播放文件名称
AudioInputStream audioInputStream;// 文件流
AudioFormat audioFormat;// 文件格式
SourceDataLine sourceDataLine;// 输出设备

List list;// 文件列表
Label labelfilepath;//播放目录显示标签
Label labelfilename;//播放文件显示标签

public MusicPlayer() {
// 设置窗体属性
setLayout(new BorderLayout());
setTitle("MP3 Music Player");
setSize(350, 370);

// 建立菜单栏
MenuBar menubar = new MenuBar();
Menu menufile = new Menu("File");
MenuItem menuopen = new MenuItem("Open", new MenuShortcut(KeyEvent.VK_O));
menufile.add(menuopen);
menufile.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
open();
}
});
menubar.add(menufile);
setMenuBar(menubar);

// 文件列表
list = new List(10);
list.addMouseListener(new MouseAdapter() {
public void mouseClicked(MouseEvent e) {
// 双击时处理
if (e.getClickCount() == 2) {
// 播放选中的文件
filename = list.getSelectedItem();
play();
}
}
});
add(list, "Center");

// 信息显示
Panel panel = new Panel(new GridLayout(2, 1));
labelfilepath = new Label("Dir：");
labelfilename = new Label("File：");
panel.add(labelfilepath);
panel.add(labelfilename);
add(panel, "North");

// 注册窗体关闭事件
addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {
System.exit(0);
}
});
setVisible(true);
}

// 打开
private void open() {
FileDialog dialog = new FileDialog(this, "Open", 0);
dialog.setVisible(true);
filepath = dialog.getDirectory();
if (filepath != null) {
labelfilepath.setText("Dir：" + filepath);

// 显示文件列表
list.removeAll();
File filedir = new File(filepath);
File[] filelist = filedir.listFiles();
for (File file : filelist) {
String filename = file.getName().toLowerCase();
if (filename.endsWith(".mp3") || filename.endsWith(".wav")) {
list.add(filename);
}
}
}
}

// 播放
private void play() {
try {
isStop = true;// 停止播放线程
// 等待播放线程停止
System.out.print("Start：" + filename);
while (!hasStop) {
System.out.print(".");
try {
Thread.sleep(10);
} catch (Exception e) {
}
}
System.out.println("");
File file = new File(filepath + filename);
labelfilename.setText("Playing：" + filename);

// 取得文件输入流
audioInputStream = AudioSystem.getAudioInputStream(file);
audioFormat = audioInputStream.getFormat();
// 转换mp3文件编码
if (audioFormat.getEncoding() != AudioFormat.Encoding.PCM_SIGNED) {
audioFormat = new AudioFormat(AudioFormat.Encoding.PCM_SIGNED,
audioFormat.getSampleRate(), 16, audioFormat
.getChannels(), audioFormat.getChannels() * 2,
audioFormat.getSampleRate(), false);
audioInputStream = AudioSystem.getAudioInputStream(audioFormat,
audioInputStream);
}

// 打开输出设备
DataLine.Info dataLineInfo = new DataLine.Info(
SourceDataLine.class, audioFormat,
AudioSystem.NOT_SPECIFIED);
sourceDataLine = (SourceDataLine) AudioSystem.getLine(dataLineInfo);
sourceDataLine.open(audioFormat);
sourceDataLine.start();

// 创建独立线程进行播放
isStop = false;
Thread playThread = new Thread(new PlayThread());
playThread.start();
} catch (Exception e) {
e.printStackTrace();
}
}

class PlayThread extends Thread {
byte tempBuffer[] = new byte[320];

public void run() {
try {
int cnt;
hasStop = false;
// 读取数据到缓存数据
while ((cnt = audioInputStream.read(tempBuffer, 0,
tempBuffer.length)) != -1) {
if (isStop)
break;
if (cnt > 0) {
// 写入缓存数据
sourceDataLine.write(tempBuffer, 0, cnt);
}
}
// Block等待临时数据被输出为空
sourceDataLine.drain();
sourceDataLine.close();
hasStop = true;
} catch (Exception e) {
e.printStackTrace();
System.exit(0);
}
}
}

public static void main(String args[]) {
new MusicPlayer();
}
}

追问

我看不懂哪里是可以使音乐顺序播放下去的，麻烦你能给我解答下不。