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http://www.zhihu.com/question/20054048http://www.cnblogs.com/luoshupeng/archive/2011/05/01/2033743.htmlhttp://www.cnblogs.com/rockhawk/archive/2010/12/15/1906956.htmlhttp://www.cnblogs.com/luoshupeng/archive/2011/04/27/2030056.htmlhttp://blog.sina.com.cn/s/blog_66a133b70100x44p.htmlhttp://blog.const 阅读全文
