http://www.cnblogs.com/fullhouse/archive/2011/07/18/2109936.html
http://www.cnblogs.com/fullhouse/archive/2011/07/18/2109936.html
http://www.itlead.com.cn/article/html/148/2012-01-31/content-7632.shtml
http://blog.csdn.net/yczz/article/details/6941365
http://www.cnblogs.com/stu-xu/archive/2011/12/07/2279017.html