android and ksoap, check web service availability

I am trying to create an android application that uses Ksoap2, I wanna check the web service availability 开发者_如何学Gobefore using any processing, because if i don't my program just crash.

Let's try SOAP UI (http://www.soapui.org/). It provides a GUI of SOAP service so that you can run and see if returned data is null or not.