Q:

Is clearing application cache, it's deleted "data/data//files" files?

Is "data/data//files" deleted when application cache cleared in android from setting page?

A:

The /data/data/<packagename>/files folder you get e.g. via Context#getFilesDir() is not cleared when the cache is cleared.
The files here will only be deleted when your app is uninstalled or the user hits the delete data button in system settings.
The /data/data/<packagename>/cache folder Context#getCacheDir() on the other hand can be cleared automatically. (or through the clear cache button in system settings)
As the documentation states

These files will be ones that get deleted first when the device runs low on storage. There is no guarantee when these files will be deleted.

