http://blog.csdn.net/yang_hui1986527/article/details/6706265
http://www.worldhello.net/gotgithub/index.html#id4
http://www.liaoxuefeng.com/wiki/0013739516305929606dd18361248578c67b8067c8c017b000/001373962845513aefd77a99f4145f0a2c7a7ca057e7570000