/** the implementation loads the URL and the soap action for the request. */
 @Override
 public void configure(TestElement el) {
   super.configure(el);
   SubscriberSampler sampler = (SubscriberSampler) el;
   urlField.setText(sampler.getProviderUrl());
   mqttDestination.setText(sampler.getDestination());
   clientId.setText(sampler.getClientId());
   mqttUser.setText(sampler.getUsername());
   mqttPwd.setText(sampler.getPassword());
   useAuth.setSelected(sampler.isUseAuth());
   mqttUser.setEnabled(useAuth.isSelected());
   mqttPwd.setEnabled(useAuth.isSelected());
   samplerTimeout.setText(sampler.getSamplerTimeout());
   iterations.setText(sampler.getIterations());
   connectionTimeout.setText("" + sampler.getConnectionTimeout());
   cleanSession.setSelected(Boolean.parseBoolean(sampler.getCLEANSESSION()));
   // typeQoSValue.setText(sampler.getQuality());
 }