通过这个类，您可以访问有关更改的信息，例如，更改是新建文件、删除还是文件更改。

Through this class, you can access information on the change, such as whether it's a new file, a deletion, or a file change.

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通过这个类，您可以设置一些必要的属性，比如Web服务实现类和端点url。

Through this class, you will set the necessary properties like the Web service implementation class and the endpoint URL.

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通过将它保持为这个类中的一个成员字段，您可以安全地缓存这些昂贵的资源。

By keeping it as a member field in this class, you can safely cache these expensive resources.

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