Android MediaPlayer与Http Proxy结合之提高篇

本文来自http://blog.csdn.net/hellogv/ ，引用.

       基础篇实现一个简单的代理服务器与Android的MediaPlayer结合(仅支持Http
Get)，可以通过代理服务器来转发MediaPlayer的Request以及传输服务器的Response，但基础篇还不能支持Seek，这次提高篇支持了Seek。代理服务器可以增强MediaPlayer对复杂的Http情况的适应，可以播放带防盗链的媒体文件，边播边存，还可以对大体积的媒体文件（如视频）进行多线程预加载，达到快速播放的效果。

       本文代码运行在模拟器上，使用Microsoft Network Monitor 3.4来抓包，通过抓包可以发现seek的操作会重新连接服务器，并在Http Get请求中加入Range 字段，所以代理服务器每次监听到MediaPlayer的request都需要新建socket与远程服务器连接。

本文的代码可以到http://download.csdn.net/detail/hellogv/4332362下载，本文程序运行效果如图：

接下来贴出核心代码HttpGetProxy.java：

[java] view
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1. public class HttpGetProxy {  
2.     final static private String TAG = "HttpGetProxy";  
3.     final static private String LOCAL_IP_ADDRESS = "127.0.0.1";  
4.     final static private int HTTP_PORT = 80;  
5.       
6.     private int local_ip_port;  
7.     private ServerSocket localServer = null;  
8.     private Socket localSocket = null;  
9.     private Socket remoteSocket = null;  
10.     private String remoteHost;  
11.   
12.     private InputStream in_remoteSocket;  
13.     private OutputStream out_remoteSocket;  
14.     private InputStream in_localSocket;  
15.     private OutputStream out_localSocket;  
16.   
17.     private SocketAddress address;  
18.     private interface OnFinishListener {  
19.         void onFinishListener();  
20.     }  
21.   
22.     /** 
23.      * 初始化代理服务器 
24.      * @param localport 代理服务器监听的端口 
25.      */  
26.     public HttpGetProxy(int localport) {  
27.         local_ip_port=localport;  
28.         try {  
29.             localServer = new ServerSocket(localport, 1,  
30.                     InetAddress.getByName(LOCAL_IP_ADDRESS));  
31.         } catch (UnknownHostException e) {  
32.             // TODO Auto-generated catch block  
33.             e.printStackTrace();  
34.         } catch (IOException e) {  
35.             // TODO Auto-generated catch block  
36.             e.printStackTrace();  
37.         }  
38.     }  
39.   
40.     /** 
41.      * 结束时，清除所有资源 
42.      */  
43.     private OnFinishListener finishListener = new OnFinishListener() {  
44.   
45.         @Override  
46.         public void onFinishListener() {  
47.             System.out.println("..........release all..........");  
48.             Log.e(TAG, "..........release all..........");  
49.             try {  
50.                 in_localSocket.close();  
51.                 out_remoteSocket.close();  
52.   
53.                 in_remoteSocket.close();  
54.                 out_localSocket.close();  
55.   
56.                 localSocket.close();  
57.                 remoteSocket.close();  
58.             } catch (IOException e) {  
59.                 // TODO Auto-generated catch block  
60.                 e.printStackTrace();  
61.             }  
62.         }  
63.     };  
64.   
65.   
66.     /** 
67.      * 把网络URL转为本地URL，127.0.0.1替换网络域名 
68.      * @param url 网络URL 
69.      * @return 本地URL 
70.      */  
71.     public String getLocalURL(String url){  
72.         String result = null;  
73.         URI originalURI=URI.create(url);  
74.         remoteHost=originalURI.getHost();  
75.         if(originalURI.getPort()!=-1){//URL带Port  
76.             address = new InetSocketAddress(remoteHost,  
77.                     originalURI.getPort());//使用默认端口  
78.             result=url.replace(remoteHost+":"+originalURI.getPort(),  
79.                     LOCAL_IP_ADDRESS+":"+local_ip_port);  
80.         }  
81.         else{//URL不带Port  
82.             address = new InetSocketAddress(remoteHost,  
83.                     HTTP_PORT);//使用80端口  
84.             result=url.replace(remoteHost,LOCAL_IP_ADDRESS+":"+local_ip_port);  
85.         }  
86.         return result;  
87.           
88.     }  
89.       
90.     /** 
91.      * 启动代理服务器 
92.      * @throws IOException 
93.      */  
94.     public void startProxy() throws IOException {  
95.           
96.         new Thread() {  
97.             public void run() {  
98.                 int bytes_read;  
99.                 byte[] local_request = new byte[1024];  
100.                 byte[] remote_reply = new byte[1024];  
101.                 while (true) {  
102.                     try {  
103.                         //--------------------------------------  
104.                         //监听MediaPlayer的请求，MediaPlayer->代理服务器  
105.                         //--------------------------------------  
106.                         localSocket = localServer.accept();  
107.   
108.                         Log.e(TAG, "..........localSocket connected..........");  
109.                         in_localSocket = localSocket.getInputStream();  
110.                         out_localSocket = localSocket.getOutputStream();  
111.                         Log.e(TAG, "..........init local Socket I/O..........");  
112.   
113.                         String buffer = "";//保存MediaPlayer的HTTP请求  
114.                         while ((bytes_read = in_localSocket.read(local_request)) != -1) {  
115.                             String str = new String(local_request);  
116.                             Log.e("localSocket---->", str);  
117.                             buffer = buffer + str;  
118.                             if (buffer.contains("GET")  
119.                                     && buffer.contains("\r\n\r\n")) {  
120.                                 // ---把request中的本地ip改为远程ip---//  
121.                                 buffer = buffer.replace(LOCAL_IP_ADDRESS,remoteHost);  
122.                                 break;  
123.                             }  
124.                         }  
125.                         Log.e(TAG, "..........local finish receive..........");  
126.   
127.                         //--------------------------------------  
128.                         //把MediaPlayer的请求发到网络服务器，代理服务器->网络服务器  
129.                         //--------------------------------------  
130.                         remoteSocket = new Socket();  
131.                         remoteSocket.connect(address);  
132.                         Log.e(TAG,"..........remote Server connected..........");  
133.                         in_remoteSocket = remoteSocket.getInputStream();  
134.                         out_remoteSocket = remoteSocket.getOutputStream();  
135.                         out_remoteSocket.write(buffer.getBytes());//发送MediaPlayer的请求  
136.                         out_remoteSocket.flush();  
137.   
138.                         //------------------------------------------------------  
139.                         //把网络服务器的反馈发到MediaPlayer，网络服务器->代理服务器->MediaPlayer  
140.                         //------------------------------------------------------  
141.                         Log.e(TAG,"..........remote start to receive..........");  
142.                         while ((bytes_read = in_remoteSocket.read(remote_reply)) != -1) {  
143.                             out_localSocket.write(remote_reply, 0, bytes_read);  
144.                             out_localSocket.flush();  
145.                         }  
146.                         Log.e(TAG, "..........over..........");  
147.                         finishListener.onFinishListener();//释放资源  
148.                     } catch (IOException e) {  
149.                         // TODO Auto-generated catch block  
150.                         e.printStackTrace();  
151.                     }  
152.                 }  
153.             }  
154.         }.start();  
155.     }  
156. }  
157.