http://www.cnblogs.com/jingmoxukong/p/5945200.html

http://www.cnblogs.com/knowledgesea/p/5175711.html

http://www.cnblogs.com/jiekzou/p/4486447.html

http://www.cnblogs.com/xiaogangqq123/archive/2011/03/02/1969006.html

看完这四篇文章应该能够入门了吧．

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