title: Java SAAJ Basic Authentication
body: <p>I have a basic SOAP service endpoint, actually SAP ECC, presenting a service.  I have tested the service using SOAPUI 4.5, and it works ok using HTTP Auth, preemptive by the looks of things.  I see an outbound "Authorization:Basic BASE64" and the service responds appropriately.</p>
  
  <p>I am now trying to roll this into Java.  I thought that I would take a SAAJ approach with:</p>
  
  <pre><code> SOAPConnectionFactory soapConnectionFactory = SOAPConnectionFactory.newInstance();
   SOAPConnection soapConnection = soapConnectionFactory.createConnection();
   String url = "http://SAPSERVER:8006/sap/bc/srt/rfc/sap/z_lookup_generic_prototype/300/z_user/z_user_binding";
   SOAPMessage message = messageFactory.createMessage();
   SOAPMessage response = connection.call(message, url);
  </code></pre>
  
  <p>But I cannot find a way to add the HTTP authentication in.  I believe that SAAJ provides the means to control the SOAP message, but how do I add authentication in?  Are there any alternatives worth considering?</p>