How to call a SOAP web service on Android

To call a web service from a mobile device (especially on an Android phone), I have used a very simple way to do it. I have not used any web service client API in attempt to call the web service. My approach is as follows to make a call.

1. Create a simple HTTP connection by using the Java standard API HttpURLConnection.
2. Form a SOAP request. (You can make help of SOAPUI to make a SOAP request.)
3. Set doOutPut flag as true.
4. Set HTTP header values like content-length, Content type, and User-agent. Do not forget to set Content-length value as it is a mandatory.
5. Write entire the SOAP request to the output stream.
6. Call the method to make a connection and receive the response (In my case I used getResonseCode).
7. If your received response code as
   200. It means you are succeeded to call web service.
8. Now take an input stream on the same HTTP connection and receive the string object. This string object is a SOAP response.
9. If the response code is other than 200 then take a ErrorInput stream on same HTTPobject and receive the error if any.
10. Parse the received response using SAXParser (in my case) or DOMParaser or any other parsing mechanism.

I have implemented this procedure for the Android phone, and it is successfully running. I am able to parse the response even if it is more than 700 KB.

It's true that due to it's overhead SOAP is not the best choice for data exchange with mobile devices. However, you might find yourself in situation in which you do not control the format of server output.

So, if you have to stick with SOAP, there is a kSOAP2 library patched for Android here:
http://code.google.com/p/ksoap2-android/

Android does not provide any sort of SOAP library. You can either write your own, or use something like kSOAP 2. As you note, others have been able to compile and use kSOAP2 in their own projects, but I haven't had to.

Google has shown, to date, little interest in adding a SOAP library to Android. My suspicion for this is that they'd rather support the current trends in Web Services toward REST-based services, and using JSON as a data encapsulation format. Or, using XMPP for messaging. But that is just conjecture.

XML-based web services are a slightly non-trivial task on Android at this time. Not knowing NetBeans, I can't speak to the tools available there, but I agree that a better library should be available. It is possible that the XmlPullParser will save you from using SAX, but I don't know much about that.

org.apache.http.impl.client.DefaultHttpClient comes in the Android SDK by default. That'll get you connected to the WSDL.

HttpClient httpClient = new DefaultHttpClient();
HttpContext localContext = new BasicHttpContext();
HttpGet httpGet = new HttpGet("http://www.example.com/" + URL);
HttpResponse response = httpClient.execute(httpGet, localContext);