Prototype

http://www.blogjava.net/pengpenglin/archive/2008/01/02/172327.html

http://terrylee.cnblogs.com/archive/2006/01/16/317896.html

http://wenku.baidu.com/view/9ecc4fa9d1f34693daef3e23.html

http://www.cnblogs.com/feipeng/archive/2007/03/13/672791.html