code: public String updateHost(final String newHost) {
          validateHostName(newHost);
  
          String oldHost = this.host;
          this.host = newHost;
  
          if (!oldHost.equals(newHost)) {
              sendNotification(new AttributeChangeNotification(this, sequenceNum.incrementAndGet(), System.currentTimeMillis(), this.toString()
                                                                                                                                + " host value changed", "Host", "java.lang.String", oldHost, newHost));
          }
  
          return oldHost;
      }
docs: Update the host value for this end point.
  Will emit an AttributeChangeNotification if the value changed.
  
  @param newHost The new (or current) host name value. If no change, no notification is sent.
  @return String The previous host value