The first release is here: https://github.com/hurui200320/jna-wintun

Now you can operate TUN device in Java on Windows. From the GitHub search result, there are currently no similar thing implemented in Java.

During this period, I do appreciate how Linux's api is much elegant and easy to work with, compared to Microsoft's win32. Especially the DWORD, ULONG, LARGE_INTEGER things. And I especially don't like using uppercase letters for variables' name.