Java程序自动下载谷歌音乐歌词
近期写了一个android音乐播放器,但是苦于找不到可以自动下载歌词的网站。网上搜的那个已经不能用了。这时候想起可以调用百度或者谷歌的接口来搜索歌词，由于谷歌刚刚推出了谷歌音乐，于是我就想着去尝试下。
进入谷歌音乐的主页，然后随便输了首歌去搜索，跳转至歌曲搜索。发现真的有歌词，可惜歌词不是嵌套在网页里的，并且打开歌词网页的地址里包含的是歌词的id，这可这么半呢？
于是我就去搜索页面寻找歌曲的id,果然在html源代码中找到了歌曲的id,然后我就用这个id拼接在歌词网址的字符串中，最后顺利地进入了歌词页面。
不过歌词页面中的信息很少，连歌词都是从别的地方读取过来的，html源代码中也没有歌词相应的地址。还好，在页面的框架信息中我看到了歌词的地址，在浏览器输入后就可以直接下载，并且下载后的文件就是歌曲的歌词，不含其他信息。
这样就有思路了：
1.接收参数为歌曲名和歌手（这样可以准确的定位歌词文件），然后把参数拼接在查询字符串后面，进行歌词页面的查询。
2.获取歌词页面的html源代码并进行解析，获取歌曲的id
3.将歌曲的id拼接在歌词框架页面地址的后面，获取歌词框架页面的html源代码
4.解析框架页面的源代码，获取歌词下载地址。
5.下载歌词并保存至文件。
需要注意的是：
1.谷歌音乐的歌曲、歌手都不是很多，有些歌曲可能搜索不到歌词，甚至谷歌就没有收录这些歌曲。
2.谷歌服务器不稳定，歌词可能会下载失败，原因大家都懂得。
3.下载的歌词默认放在工程目录下，可以自行修改歌词位置。
4.谷歌音乐页面编码都是UTF-8的，不需要考虑乱码的问题。
PS：本程序仅仅是抛砖引玉,具体怎么使用就看大家的了。
下面上代码：
工具类
[java]
<span style=”font-family:FangSong_GB2312;”><span style=”font-size: 14px;”></span></span><pre name=”code” class=”java”>package com.zyc.download_lrc;
/**
* Get lrc from google music
* Version 1.00
* @author zyc
* 2012.2.2
*/
/*
* Step:
* 1.Input music’s name and artist,use google music search engine
* The url like ”http://www.google.cn/music/search?q=name+artist”
* 2.Get music id,the id is starts with ”http://g.top100.cn/16667639/html/lyrics.html?id”
* and id is after
* 3.Use id to get lrc framework html,find download lrc url
* 4.download lrc
* 5.write lrc to file
*
* NOTICE:google work may abnormal,you known
*/
import java.io.BufferedReader;
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.SocketTimeoutException;
import java.net.URL;
import java.net.URLConnection;
public class DownloadGoogleLrcTool {
/*music info start,but can’t get id from this,because the music has no lrc*/
private final static String ID_HEAD_FLAG = ”<!–freemusic”;
/*google music engine search head*/
private final static String SEARCH_ENGINE_HEAD = ”http://www.google.cn/music/search?q=”;
/*google music lrc by id head*/
private final static String SEARCH_ID_URL_HEAD = ”http://www.google.cn/music/top100/lyrics?id=”;
/*google music id flag*/
private final static String SEARCH_ID_FLAG = ”http://g.top100.cn/16667639/html/lyrics.html?id”;
/*google music download url flag*/
private final static String SEARCH_LRC_DOWNLOAD_URL_FLAG = ”http://lyric.top100.cn/”;
/*”%3D” means ”=”*/
private final static String SEARCH_HTML_EQUAL = ”%3D”;
private final static String END_FLAG = ”\\”;
private final static String LRC_SUFFIX = ”.lrc”;
private final static String LINE_END = ”\n”;
/*google music can’t connect return code”*/
private final static String GOOGLE_SB_RETURN_CODE = ”502″;
/*error message,you know”*/
private final static String GOOGLE_SB_MESSAGE = ”google抽风中…你懂的\n请稍后再试”;
private final static String SPACE = ” ”;
/*”%20″ means ” ”*/
private final static String HTML_SPACE = ”%20″;
private final static String HTML_URL_HEAD = ”http://”;
/*id is letter and number”*/
private final static String ID_MATCH = ”^[A-Za-z0-9]+{1}quot;;
/*download message*/
private final static String CANNOT_FIND_LEC_MESSAGE = ”无法找到歌词”;
private final static String FAIL_MESSAGE = ”下载歌曲 %s-%s 歌词 失败！\n原因：”;
private final static String SUCCESS_MESSAGE = ”下载歌曲 %s-%s 歌词 成功！\n歌词位置: %s\n”;
private final static String DOWNLOADING_MESSAGE = ”正在下载歌曲 %s-%s 歌词…\n”;
/*time out message*/
private final static String DOWNLOADING_CONNECT_TIME_OUT = ”connect timed out”;
private final static String DOWNLOADING_CONNECT_TIME_OUT_MESSAGE = ”连接超时，请检查网络配置”;
private final static String DOWNLOADING_UNKNOWN_MESSAGE = ”未知”;
/*set timeout = 5s*/
private final static long CONNECT_TIME_OUT = 5000;
/*set http proxy,if don’t use http proxy,set it false*/
private final static boolean USE_HTTP_PROXY = true;
private final static String FAIL_WRITE_FILE_MESSAGE = ”写入文件失败!”;
public static void downloadLrcFromGoogle(String name,String artist){
try {
System.out.printf(DOWNLOADING_MESSAGE,name,artist);
/*get lrc*/
String lrc = downloadLrc(name,artist);
if(lrc != null){
/*write lrc to file*/
String fileName = name + LRC_SUFFIX;
File file = new File(fileName);
writeToFile(file, lrc);
System.out.printf(SUCCESS_MESSAGE, name,artist,file.getAbsoluteFile());
}
else
System.out.println(CANNOT_FIND_LEC_MESSAGE);
} catch (Exception e) {
System.out.printf(FAIL_MESSAGE, name,artist);
if(e.getMessage().contains(GOOGLE_SB_RETURN_CODE))
System.out.println(GOOGLE_SB_MESSAGE);
else if(e.getMessage().contains(DOWNLOADING_CONNECT_TIME_OUT)){
System.out.println(DOWNLOADING_CONNECT_TIME_OUT_MESSAGE);
}
else {
System.out.println(DOWNLOADING_UNKNOWN_MESSAGE);
}
//e.printStackTrace();
}
}
private static void init(){
System.setProperty(“sun.net.client.defaultConnectTimeout”, String.valueOf(CONNECT_TIME_OUT));
if(USE_HTTP_PROXY){
//add http proxy setting here
}
}
private static String downloadLrc(String name,String artist) throws IOException,SocketTimeoutException{
init();
/*replace ” ” to ”%2d”*/
name = name.replaceAll(SPACE, HTML_SPACE);
artist = artist.replaceAll(SPACE, HTML_SPACE);
String id = getSongId(name, artist);
/*can’t find id return null”*/
if(id == null || !id.matches(ID_MATCH)){
return null;
}
String path = getLrcDownloadUrl(id);
String lrc = null;
/*if path isn’t start with ”http”//” ignore*/
if(path.startsWith(HTML_URL_HEAD))
lrc = doDownloadLrc(path);
return lrc;
}
private static String getSongId(String name,String artist) throws IOException{
String source = readHtml(SEARCH_ENGINE_HEAD + name + ”+” + artist);
name = name.replaceAll(HTML_SPACE, SPACE);
String match01 = ”\”><b>” + name + ”</b>”;
String match02 = null;
if(name.contains(SPACE)){
/*set first letter upper*/
String[] array = name.split(SPACE);
for (int i = 0;i < array.length;i++) {
char firstChar = array[i].charAt(0);
if(firstChar >= ’a' && firstChar <= ’z'){
array[i] = array[i].replace(firstChar, (char) (firstChar - 32));//set upper
}
}
String newName = ”";
for (int i = 0;i < array.length;i++) {
if(i < array.length - 1)
newName += array[i] + SPACE;
else
newName += array[i];
}
match02 = ”\”><b>” + newName + ”</b>”;
}
if(!source.contains(match01) && match02 != null && !source.contains(match02)){
/*may other music return*/
return null;
}
int first = source.indexOf(ID_HEAD_FLAG);
if(first == -1){
/*no music id*/
return null;
}
int last = source.indexOf(ID_HEAD_FLAG,first + ID_HEAD_FLAG.length());
if(last != -1){
/*ignore only a music id,if have some choose first one*/
source = source.substring(first,last);
}
/*find id*/
int start = source.indexOf(SEARCH_ID_FLAG);
int mid = source.indexOf(SEARCH_HTML_EQUAL, start);
int end = source.indexOf(END_FLAG,mid);
if(start == -1 || mid == -1 || end == -1){
//can’t find id
return null;
}
String id = source.substring(mid + HTML_SPACE.length(), end);
return id;
}
private static String getLrcDownloadUrl(String id) throws IOException{
/*set music lrc html url with id*/
String source = readHtml(SEARCH_ID_URL_HEAD + id);
int start = source.indexOf(SEARCH_LRC_DOWNLOAD_URL_FLAG);
int end = source.indexOf(LRC_SUFFIX,start);
String urlString = source.substring(start, end + LRC_SUFFIX.length());
return urlString;
}
private static String doDownloadLrc(String path) throws IOException{
/*download lrc*/
return readHtml(path);
}
private static String readHtml(String urlPath) throws IOException{
/*use google music search engine*/
URL url = new URL(urlPath);
/*connect and get html */
URLConnection conn = url.openConnection();
BufferedReader reader = new BufferedReader(new InputStreamReader(conn.getInputStream()));
String line = null;
StringBuilder stringBuilder = new StringBuilder();
while ((line = reader.readLine()) != null) {
stringBuilder.append(line + LINE_END);
}
return stringBuilder.toString();
}
private static void writeToFile(File file,String buffer) throws IOException{
/*write to file,file name is music’s name + ”.lrc”*/
FileWriter writer = new FileWriter(file, false);
try {
writer.write(buffer);
} catch (Exception e) {
System.out.println(FAIL_WRITE_FILE_MESSAGE);
}finally{
writer.close();
}
}
}
测试类
[java]
<span style=”font-family:FangSong_GB2312;”><span style=”font-size: 14px;”></span></span><pre name=”code” class=”java”>package com.zyc.download_lrc;
public class DownloadTest {
public static void main(String[] args) {
//only for test
String name = ”决战斗室”;
String artist = ”潘玮柏”;
downloadMusicLrc(name, artist);
}
static void downloadMusicLrc(String name,String artist){
DownloadGoogleLrcTool.downloadLrcFromGoogle(name, artist);
}
}
测试结果：
正在下载歌曲 决战斗室-潘玮柏 歌词…
下载歌曲 决战斗室-潘玮柏 歌词 成功！
歌词位置: /project/DownLoadLrc/决战斗室.lrc
歌词如下：
[ti:决战斗室]
[ar:潘玮柏]
[al:高手]
[00:05.00]
[01:20.44][00:16.69]克制不住 心跳加速
[01:22.27][00:18.67]太兴奋追求战斗我才满足
[01:24.25][00:20.47]角落处 全神贯注
[01:26.25][00:22.57]眼神冰冷像只危险老虎
[01:28.23][00:24.58]拳头蹦带 无法束缚
[01:30.25][00:26.55]脉膊跳动的强度快忍不住
[01:32.22][00:28.51]灯在闪 人群在喊
[01:34.19][00:30.48]抬起头我完全不屑一顾
[01:36.21][00:32.60]Noboby gonna stop me
[01:38.21][00:34.57]沉默中 聆听自己
[01:40.07][00:36.54]Noboby gonna front me
[01:42.23][00:38.51]相信自己 绝不会逃避
[01:44.25][00:40.55]Noboby gonna touch me
[01:46.19][00:42.48]呐喊声全场淹没
[01:48.12][00:44.41]推开门 走出自我
[01:50.06][00:46.22]This is my life my soul
[02:44.39][02:28.08][01:52.15][00:48.47]紧握灵魂的手
[02:45.75][02:29.93][01:54.03][00:50.35]最后一刻战斗
[02:47.86][02:31.96][01:56.10][00:52.38]黑暗恐惧之中
[02:50.61][02:33.71][01:57.84][00:54.19]决战斗室只剩你我
[02:51.86][02:35.86][02:00.09][00:56.38]倒数的计时钟
[02:53.77][02:37.90][02:02.00][00:58.30]胜利才终结转动
[02:57.37][02:41.51][02:05.59][01:01.84]我闭上眼我站在斗室中
[02:59.29][02:43.35][02:07.50][01:03.94]只剩下Oh oh
然后就可以放进手机同步播放了！
搞定！！！
