String readMcastHostAddress() {
    String result = null;
    if (optionalFields != null) {
      result = optionalFields.getProperty(MCAST_HOST_ADDRESS);
    }
    return result;
  }
Write the value for the optional field {@link #HOSTED_LOCATORS}.
geode-core/src/main/java/org/apache/geode/distributed/internal/StartupMessageData.java