The following code fragment from the SDK\vsphere-ws\java\JAX-WS\samples\com\vmware\vm\
VMPromoteDisks.java sample shows another implementation of the server connection. Review the stand-alone Java samples that are shipped with your vSphere Web Services SDK, and use similar code to get a session token for your client application.

Obtaining a Session Token - Code Fragments from VMPromoteDisks.java

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   private static String cookieValue = "";
   private static Map headers = new HashMap();
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   private static void trustAllHttpsCertificates()
      throws Exception {

      javax.net.ssl.TrustManager[] trustAllCerts = new javax.net.ssl.TrustManager[1];
      javax.net.ssl.TrustManager tm = new TrustAllTrustManager();
      trustAllCerts[0] = tm;
      javax.net.ssl.SSLContext sc = javax.net.ssl.SSLContext.getInstance("SSL");
      javax.net.ssl.SSLSessionContext sslsc = sc.getServerSessionContext();
      sslsc.setSessionTimeout(0);
      sc.init(null, trustAllCerts, null);
      javax.net.ssl.HttpsURLConnection.setDefaultSSLSocketFactory(sc.getSocketFactory());
   }
   ...
   private static void connect()
      throws Exception {

      HostnameVerifier hv = new HostnameVerifier() {
         public boolean verify(String urlHostName, SSLSession session) {
            return true;
         }
      };
      trustAllHttpsCertificates();
      HttpsURLConnection.setDefaultHostnameVerifier(hv);

      SVC_INST_REF.setType(SVC_INST_NAME);
      SVC_INST_REF.setValue(SVC_INST_NAME);

      vimService = new VimService();
      vimPort = vimService.getVimPort();
      Map<String, Object> ctxt =
         ((BindingProvider) vimPort).getRequestContext();

      ctxt.put(BindingProvider.ENDPOINT_ADDRESS_PROPERTY, url);
      ctxt.put(BindingProvider.SESSION_MAINTAIN_PROPERTY, true);

      serviceContent = vimPort.retrieveServiceContent(SVC_INST_REF);
      headers =
         (Map) ((BindingProvider) vimPort).getResponseContext().get(
                 MessageContext.HTTP_RESPONSE_HEADERS);
      vimPort.login(serviceContent.getSessionManager(),
                    userName,
                    password, null);
      isConnected = true;

      propCollectorRef = serviceContent.getPropertyCollector();
      rootRef = serviceContent.getRootFolder();
   }
   ...