http://www.blogjava.net/crespochen/archive/2011/04/22/348819.html

http://blog.****.net/supersky07/article/details/7407523

http://blog.****.net/cuker919/article/details/8840221

http://www.blogjava.net/crespochen/archive/2011/04/22/348819.html

http://www.cnblogs.com/xwdreamer/p/3466661.html