1. http://www.cnblogs.com/felixfly/archive/2011/12/07/2279321.html
2. http://bkship.iteye.com/blog/1182243
3. http://www.cnblogs.com/slider/archive/2012/02/13/2349508.html
4. http://blog.csdn.net/evilcode/article/details/5699786
5. http://blog.csdn.net/xjanker2/article/details/6303927
