http://www.blogjava.net/crazycy/archive/2014/07/12/415738.html
http://my.oschina.net/u/205170/blog/152438
http://my.oschina.net/ydsakyclguozi/blog/413822
http://blog.csdn.net/woshiwxw765/article/details/7603497
原文：http://www.cnblogs.com/diyunpeng/p/5025449.html