Although you don't necessarily need to understand the SOAP messages passed between the web service and the client, sometimes inspecting SOAP messages exchanged between the two could help debug some of the issues.
You can print request and response SOAP messages when running the client quite easily by setting the following system property:
com.sun.xml.internal.ws.transport.http.client.HttpTransportPipe.dump=true
In Eclipse, right-click on the CourseMgmtWSClient class and select Run As | Run Configurations. Click on the Arguments tab and specify the following VM argument:
Dcom.sun.xml.internal.ws.transport.http.client.HttpTransportPipe.dump=true
Figure 9.11: Set VM arguments
Click Run. You will see request and response ...
