本文介紹的是mediaplayer實(shí)現(xiàn)邊下邊播的一種方法。
原理：創(chuàng)建兩個(gè)socket服務(wù)，遠(yuǎn)程socket和本地socket，遠(yuǎn)程socket用于請(qǐng)求播放資源真實(shí)的數(shù)據(jù)，本地socket用于監(jiān)聽mediaplayer請(qǐng)求，并且將遠(yuǎn)程socket獲取到的數(shù)據(jù)，寫到mediaplyer中進(jìn)行播放。
為什么需要采用兩個(gè)socket?
如果只采用一個(gè)socket代理，歌曲可以播放正常，但是mediaplayer的seekTo方法失效，原因是mediaplayer在請(qǐng)求數(shù)據(jù)的時(shí)候缺少了一些請(qǐng)求數(shù)據(jù)，導(dǎo)致mediaPlayer的duration一直為0，所以無法進(jìn)行seekTo操作。
詳細(xì)步驟：
一，初始化本地socket代理
public MediaPlayerProxy(String writeFileName, boolean writeFile) throws Exception {
proxyIdle = false;
this.writeFile = writeFile;
this.writeFileName = writeFileName;
try {
if (localServer == null || localServer.isClosed()) {
//創(chuàng)建本地socket服務(wù)器，用來監(jiān)聽mediaplayer請(qǐng)求和給mediaplayer提供數(shù)據(jù)
localServer = new ServerSocket();
localServer.setReuseAddress(true);
InetSocketAddress socketAddress = new InetSocketAddress(InetAddress.getByName(LOCAL_IP_ADDRESS), local_ip_port);
localServer.bind(socketAddress);
}
} catch (Exception e) {
LogTool.ex(e);
try {
local_ip_port--;
localServer = new ServerSocket(local_ip_port, 0, InetAddress.getByName(LOCAL_IP_ADDRESS));
localServer.setReuseAddress(true);
} catch (Exception e2) {
LogTool.ex(e2);
throw new Exception();
}
}
}
二、根據(jù)真實(shí)的請(qǐng)求音源地址，得到本地的音源地址，將本地音源地址通過setDataSource的方式傳遞給mediaplayer. 前面創(chuàng)建的本地socket對(duì)象監(jiān)聽這個(gè)地址，用于獲取mediaplayer的請(qǐng)求數(shù)據(jù)。
public String getLocalURLAndSetRemotSocketAddr(String url) {
try {
//真實(shí)的播放地址
remotUrl = url;
if (writeFile) {
bufferingMusicUrlList.add(remotUrl);
}
String localProxyUrl = "";
final URI originalURI = URI.create(url);
final String remoteHost = originalURI.getHost();
if (!TextUtils.isEmpty(remoteHost)) {
if (originalURI.getPort() != -1) {//URL帶Port
new Thread(new Runnable() {
@Override
public void run() {
remoteAddress = new InetSocketAddress(remoteHost, originalURI.getPort());
}
}).start();
//將真實(shí)的播放地址替換成本地的代理地址
localProxyUrl = url.replace(remoteHost + ":" + originalURI.getPort(), LOCAL_IP_ADDRESS + ":" + local_ip_port);
remoteHostAndPort = remoteHost + ":" + originalURI.getPort();
} else {//URL不帶Port
if (!TextUtils.isEmpty(remoteHost)) {
new Thread(new Runnable() {
@Override
public void run() {
remoteAddress = new InetSocketAddress(remoteHost, HTTP_PORT);//使用80端口
}
}).start();
//將真實(shí)的播放地址替換成本地的代理地址
localProxyUrl = url.replace(remoteHost, LOCAL_IP_ADDRESS + ":" + local_ip_port);
remoteHostAndPort = remoteHost;
}
}
}
return localProxyUrl;
} catch (Exception e) {
LogTool.ex(e);
return "";
}
}
三、本地socket監(jiān)聽mediaplayer,通過getInputStream方法可以獲取到mediaplayer傳遞過來的請(qǐng)求信息數(shù)據(jù)，由于我們是通過本地代理地址的方式獲取到的，所以我們需要根據(jù)這個(gè)本地的請(qǐng)求信息替換成真實(shí)的遠(yuǎn)程socket請(qǐng)求信息，向服務(wù)器獲取真實(shí)請(qǐng)求數(shù)據(jù)。
public void getTrueSocketRequestInfo(Socket localSocket) throws Exception {
InputStream in_localSocket = localSocket.getInputStream();
String trueSocketRequestInfoStr = "";//保存MediaPlayer的真實(shí)HTTP請(qǐng)求
byte[] local_request = new byte[1024];
while (in_localSocket.read(local_request) != -1) {
String str = new String(local_request);
trueSocketRequestInfoStr = trueSocketRequestInfoStr + str;
if (trueSocketRequestInfoStr.contains("GET") && trueSocketRequestInfoStr.contains("\r\n\r\n")) {
//把request中的本地ip改為遠(yuǎn)程ip
trueSocketRequestInfoStr = trueSocketRequestInfoStr.replace(LOCAL_IP_ADDRESS + ":" + local_ip_port, remoteHostAndPort);
this.trueSocketRequestInfoStr = trueSocketRequestInfoStr;
//如果用戶拖動(dòng)了進(jìn)度條，因?yàn)橥蟿?dòng)了滾動(dòng)條還有Range則表示本地歌曲還未緩存完，不再保存
if (trueSocketRequestInfoStr.contains("Range")) {
LogTool.s("=Range=");
writeFile = false;
}
break;
}
}
}
四、 上一步我們獲取到了真實(shí)的請(qǐng)求數(shù)據(jù)信息，此時(shí)通過遠(yuǎn)程socket連接遠(yuǎn)程請(qǐng)求。
public Socket sendRemoteRequest() throws Exception {
//創(chuàng)建遠(yuǎn)程socket用來請(qǐng)求網(wǎng)絡(luò)數(shù)據(jù)
Socket remoteSocket = new Socket();
remoteSocket.connect(remoteAddress, socketTimeoutTime);
remoteSocket.getOutputStream().write(trueSocketRequestInfoStr.getBytes());
remoteSocket.getOutputStream().flush();
return remoteSocket;
}
五、將遠(yuǎn)程socket的數(shù)據(jù)，通過本地socket寫入mediaplayer進(jìn)行播放。
public void processTrueRequestInfo(Socket remoteSocket, Socket localSocket) {
//如果要寫入本地文件的實(shí)例聲明
FileOutputStream fileOutputStream = null;
File theFile = null;
try {
//獲取音樂網(wǎng)絡(luò)數(shù)據(jù)
InputStream in_remoteSocket = remoteSocket.getInputStream();
if (in_remoteSocket == null) return;
OutputStream out_localSocket = localSocket.getOutputStream();
if (out_localSocket == null) return;
//如果要寫入文件，配置相關(guān)實(shí)例
if (writeFile) {
File dirs = new File(Environment.getExternalStorageDirectory() + File.separator + "clearlee_music");
dirs.mkdirs();
theFile = new File(dirs + File.separator + writeFileName + ".m4a");
fileOutputStream = new FileOutputStream(theFile);
}
try {
int readLenth;
byte[] remote_reply = new byte[4096];
boolean firstData = true;//是否循環(huán)中第一次獲得數(shù)據(jù)
//當(dāng)從遠(yuǎn)程還能取到數(shù)據(jù)且播放器還沒切換另一首網(wǎng)絡(luò)音樂
while ((readLenth = in_remoteSocket.read(remote_reply, 0, remote_reply.length)) != -1 && currProxyId == lastProxyId) {
//首先從數(shù)據(jù)中獲得文件總長度
try {
if (firstData) {
firstData = false;
String str = new String(remote_reply, "utf-8");
Pattern pattern = Pattern.compile("Content-Length:\\s*(\\d+)");
Matcher matcher = pattern.matcher(str);
if (matcher.find()) {
//獲取數(shù)據(jù)的大小
fileTotalLength = Long.parseLong(matcher.group(1));
}
}
} catch (Exception e) {
LogTool.ex(e);
}
//把遠(yuǎn)程sokcet拿到的數(shù)據(jù)用本地socket寫到mediaplayer中播放
try {
out_localSocket.write(remote_reply, 0, readLenth);
out_localSocket.flush();
} catch (Exception e) {
LogTool.ex(e);
}
//計(jì)算當(dāng)前播放時(shí)，其在seekbar上的緩沖值,并刷新進(jìn)度條
try {
cachedFileLength += readLenth;
if (fileTotalLength > 0 && currProxyId == lastProxyId) {
currMusicCachedProgress = (int) (Common.div(cachedFileLength, fileTotalLength, 5) * 100);
if (mOnCaChedProgressUpdateListener != null && currMusicCachedProgress <= 100) {
mOnCaChedProgressUpdateListener.updateCachedProgress(currMusicCachedProgress);
}
}
} catch (Exception e) {
LogTool.ex(e);
}
//如果需要緩存數(shù)據(jù)到本地，就緩存到本地
if (writeFile) {
try {
if (fileOutputStream != null) {
fileOutputStream.write(remote_reply, 0, readLenth);
fileOutputStream.flush();
}
} catch (Exception e) {
LogTool.ex(e);
}
}
}
//如果是因?yàn)榍袚Q音樂跳出循環(huán)的，當(dāng)前音樂播放進(jìn)度，小于 seekbar最大值的1/4,就把當(dāng)前音樂緩存在本地的數(shù)據(jù)清除了
if (currProxyId != lastProxyId && currPlayDegree < 25) {
bufferingMusicUrlList.remove(remotUrl);
if (theFile != null) {
Common.deleteFile(theFile.getPath());
}
}
} catch (Exception e) {
LogTool.ex(e);
if (theFile != null) {
Common.deleteFile(theFile.getPath());
}
bufferingMusicUrlList.remove(remotUrl);
} finally {
in_remoteSocket.close();
out_localSocket.close();
if (fileOutputStream != null) {
fileOutputStream.close();
//音頻文件緩存完后處理
if (theFile != null && Common.checkFileExist(theFile.getPath())) {
conver2RightAudioFile(theFile);
if (musicControlInterface != null) {
musicControlInterface.updateBufferFinishMusicPath(musicKey, theFile.getPath());
bufferingMusicUrlList.remove(remotUrl);
}
}
}
localSocket.close();
remoteSocket.close();
}
} catch (Exception e) {
LogTool.ex(e);
if (theFile != null) {
Common.deleteFile(theFile.getPath());
}
bufferingMusicUrlList.remove(remotUrl);
}
}
至此，mediaplayer便實(shí)現(xiàn)了邊下邊播的功能。
詳細(xì)代碼已上傳至github，地址：https://github.com/Clearlee/PlayWhileDownloadMusic
