How to explore com.wm.util

I found the usage(call) of the generate() method in some java service developed by some person. when i am tracing the code, i found it.
I am also supposed to use this method for generating a unique id for my service.
I tried to find the UUID class in com.wm.util package in Java API, but could not!!.
I found only Values, LocalizedException and Table classes existing and not UUID class!!!