I used dlib myself, and yes, it is a very advanced and accurate library. As far as I know, there is no port in Java. But you can always compile it into a shared library (.so on linux or .dll on Windows), and then use it inside your Java code.
Read more about using dll or using in java
It is also possible to use the C ++ library directly in Java using proxies. You can look at it.
Change: . According to a comment by @evgeniy, most dlib are header-only templates. You cannot use them if you export dlib directly as a shared library. Instead, you can open all the necessary APIs, here
2:. @davis-king, swig cmake, Java/apl: mita/dlib: . .