I required IPv4 address of my blackberry device of WIFI which it is connected.
The IPv4 address which is displayed in Settings -> About -> Category Network => WIFI
The same address I have to access programmatically.
From the documentation, the Wifi service is only available in C.
If you don't want to deal with C, I think that reading the file mentionned down below with PPS and mixing default_gateway first entry with fib should give you the correct IPv4, but I'm not sure as I don't know much about networking lingo.
/pps/services/networking/all/status_public
You'll find many many example on how to read files with PPS on my GitHub or in the official documentation.