web services - SOAP Webservice call from Java gives "Object reference not set to an instance of an object"

Question

I have a requirement where I call a SOAP based web service from Java using Axis2 from eclipse. The web service code is in C#, with a BasicHttpBinding.

But when I call the method from the client stub I get this error.

org.apache.axis2.AxisFault: Object reference not set to an instance of an object.

Could anyone help me figure out this one? Is this on the service side or on the client side? Previously I got 'Internal Server error' and then they had to add something so that I can see this error in the logs.

Answer 1

The message is from the C# web service side ("Object reference not set to an instance of an object" is basically a Java equivalent of NullPointerException) but it might be because of something you send from your Java client or maybe you don't send.

The error usually means that you didn't send a required parameter and that the web service didn't do a proper job of validating it's input and missing parameter got to a point when caused the NullReferenceException.

But there is only one way to be sure, and that is to troubleshoot the call.

I suggest you use something like SoapUI to create a message and send that to the service. Once you get a succesfull call in SoapUI, make a call with the same parameters from your Java client and see what happens. When you do that, using a proxy for logging is very useful to see if the sent message is actually the expected one.