code: private Message receiveSelected(TestContext context, String selectorString) {
          if (log.isDebugEnabled()) {
              log.debug("Setting message selector: '" + selectorString + "'");
          }
  
          Endpoint messageEndpoint = getOrCreateEndpoint(context);
          Consumer consumer = messageEndpoint.createConsumer();
          if (consumer instanceof SelectiveConsumer) {
              if (receiveTimeout > 0) {
                  return ((SelectiveConsumer) messageEndpoint.createConsumer()).receive(
                          context.replaceDynamicContentInString(selectorString),
                          context, receiveTimeout);
              } else {
                  return ((SelectiveConsumer) messageEndpoint.createConsumer()).receive(
                          context.replaceDynamicContentInString(selectorString),
                          context, messageEndpoint.getEndpointConfiguration().getTimeout());
              }
          } else {
              log.warn(String.format("Unable to receive selective with consumer implementation: '%s'", consumer.getClass()));
              return receive(context);
          }
      }
docs: Receives the message with the respective message receiver implementation
  also using a message selector.
  @param context the test context.
  @param selectorString the message selector string.
  @return