docs: private Properties createPropertyNames()
      {
  
          Properties propertyNames = new Properties();
  
          propertyNames.setProperty(HOST, "mail.host");
          propertyNames.setProperty(USER, "mail.user");
          propertyNames.setProperty(FROM, "mail.from");
          propertyNames.setProperty(TRANSPORTPROTOCOL, "mail.transport.protocol");
          propertyNames.setProperty(STOREPROTOCOL, "mail.store.protocol");
  
          return propertyNames;
      }