often using website

secure:

https://www.leavesongs.com/

http://www.waitalone.cn/

android:

http://www.wjdiankong.cn/

https://developer.android.com/index.html

HDFS:

https://my.oschina.net/crxy/blog/348868

Flume:

http://www.blogjava.net/paulwong/archive/2013/10/31/405860.html