java模拟实现优酷视频真实地址解析

用java实现优酷视频真实地址的解析,网上搜集了下资料，通过自己研究写了份java代码，跟大家一起分享下.大体的思路:原始URL--->ID---->后门URL---->JSON---->JSON关键参数分析组合----->下载地址.

例如：http://v.youku.com/v_show/id_XNzg5Mjk1MzAw.html，在这个地址里,我们要提取一个重要字符串,也就是这个视频的唯一ID:XNzg5Mjk1MzAw，将这个ID加入优酷后门,组成一个URL:http://v.youku.com/player/getPlayList/VideoIDS/+ ID，如:http://v.youku.com/player/getPlayList/VideoIDS/XNzg5Mjk1MzAw

将此URL打开,可以发现这是个JSON,我们需要的就是data里面的一些东西.

真实url的构造形式:

"http://k.youku.com/player/getFlvPath/sid/" + sid + "_" + String.format("%1$02X", i) + "/st/" + format + "/fileid/" + idLeft + String.format("%1$02X", i) + idRight + "?K=" + k+"&ts="+seconds

java代码的实现：

package stateam.youku;

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.net.URL;
import java.net.URLConnection;

import org.json.JSONArray;
import org.json.JSONObject;


public class VideoGet {
	private static String sign = "mp4";
	
	private static String getFileID(String fileid, double seed){//vid
		 //System.out.println("正在分析fileid(vid)....");
		 String mixed = getFileIDMixString(seed);
		 //System.out.println("fileid: "+fileid);
		 String[] ids = fileid.split("\\*");
		 StringBuilder realId = new StringBuilder();
		 int idx;
		 for (int i = 0; i < ids.length; i++) {
		 idx = Integer.parseInt(ids[i]);//string to int
		 realId.append(mixed.charAt(idx));
		 }
		 //System.out.println("vid分析完成，值为: "+realId.toString());
		 return realId.toString();
	}
	
	private static String getFileIDMixString(double seed){ //mixed
		//System.out.println("正在分析mixed...........");
		StringBuilder mixed = new StringBuilder();
		StringBuilder source = new StringBuilder("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ/\\:._-1234567890");
		int index, len = source.length();
		for (int i = 0; i < len; ++i)
		{
		   seed = (seed * 211 + 30031) % 65536;
		   index = (int) Math.floor(seed / 65536 * source.length());//向下取整
		   mixed.append(source.charAt(index));
		   source.deleteCharAt(index);
		}
		//System.out.println("mixed分析完成，值为: "+mixed.toString());
		return mixed.toString();
	}
	
	public static String getSid(){ //sid 
		int i1 = (int) (1000 + Math.floor(Math.random() * 999)); 
		int i2 = (int) (1000 + Math.floor(Math.random() * 9000)); 
		return System.currentTimeMillis() + "" + i1 + "" + i2; 
	}
	private static String UrlConnection(String strUrl){
    	try {
		    URL url = new URL(strUrl);
			URLConnection uc = url.openConnection();// 生成连接对象
			uc.setConnectTimeout(5000);
	        uc.connect(); // 发出连接
	        StringBuffer sb = new StringBuffer();  
	        String temp; 
	        BufferedReader in = new BufferedReader(new InputStreamReader(uc.getInputStream(), "gbk"));// 读取网页全部内容  
	        while ((temp = in.readLine()) != null) {  
	        	sb.append(temp);  
	        }  
	        return sb.toString();
		} 
		catch (Exception e) {
			
		}
    	return null;
    }
	public static void main(String[] args) {
		String strUrl = "http://v.youku.com/player/getPlayList/VideoIDS/XNzg5Mjk1MzAw";
		String strJson = null;
		try {
		    strJson = UrlConnection(strUrl);
		} catch (Exception e) {
		}
		if(strJson == null)
			return;
		JSONObject jsobj = new JSONObject(strJson);
		JSONArray jsonarr = jsobj.getJSONArray("data");//jsobj为获取的json
		JSONObject obj1 = jsonarr.getJSONObject(0);
		double seed = obj1.getDouble("seed");
		JSONObject obj2 = obj1.getJSONObject("streamfileids");
		String mp4id = obj2.getString("mp4");
		String realfileid = getFileID(mp4id, seed);
		String idLeft = realfileid.substring(0, 8);
		String idRight = realfileid.substring(10);
		JSONObject obj3 = obj1.getJSONObject("segs");
		JSONArray aaa = obj3.getJSONArray(sign);
		JSONObject o = aaa.getJSONObject(0);
		String k = o.getString("k");
		String seconds = Integer.toString(o.getInt("seconds"));
		int i = 0;
		String sid = getSid();
		String format = "mp4";
		String url = "http://k.youku.com/player/getFlvPath/sid/" + sid + "_"
				+ "" + String.format("%1$02X", i) + "/st/"
				+ "" + format + "/fileid/" + idLeft + String.format("%1$02X", i) + idRight + "?K="
				+ "" + k+"&ts="+seconds;
		//System.out.println(k);
		System.out.println(url);
	}
	
}

这样,得出的是优酷的完整下载地址,一般而言,优酷基本上是对大于7分钟的视频进行分段的,所以aaa.length()这个循环必不可少,循环次数i加入String.format("%1$02X", i)中.