code: @PreDestroy
      public void releaseConnections() throws JMSException {
          LOGGER.debug("Tearing down: {}", this.getClass().getCanonicalName());
  
          producer.close();
          jmsSession.close();
          connection.close();
          eventBus.unregister(this);
      }
docs: Close external connections
  
  @throws JMSException if JMS exception occurred