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Apache Licence是著名的非盈利开源组织Apache采用的协议。
该协议和BSD类似，鼓励代码共享和尊重原作者的著作权，
允许代码修改，再作为开源或商业软件发布。需要满足
的条件： 
1． 需要给代码的用户一份Apache Licence ；
2． 如果你修改了代码，需要在被修改的文件中说明；
3． 在延伸的代码中（修改和有源代码衍生的代码中）需要
带有原来代码中的协议，商标，专利声明和其他原来作者规
定需要包含的说明；
4． 如果再发布的产品中包含一个Notice文件，则在Notice文
件中需要带有本协议内容。你可以在Notice中增加自己的
许可，但不可以表现为对Apache Licence构成更改。 
具体的协议参考：http://www.apache.org/licenses/LICENSE-2.0

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