Android : ADB tcpip command without cable

I need remote ADB shell.. I know that we have to issue "ADB tcpip ".. to change ADB server to TCP listening mode.

But, the problem is that my phone is not rooted, and I do not have USB cable. I can't issue tcpip command since I do not have USB cable,, I can't change default.prop file as the phone is not rooted.

Is there any other ways to change ADB server to TCP listening mode???