code: public void updateDBDriverClassName() {
  
          Set<String> keys = new HashSet<String>();
          // replace MySQL JDBC driver class name
          CmsParameterConfiguration properties = getProperties();
          for (Entry<String, String> propertyEntry : properties.entrySet()) {
              if (MYSQL_DRIVER_CLASS_OLD.equals(propertyEntry.getValue())) {
                  keys.add(propertyEntry.getKey());
              }
          }
          for (String key : keys) {
              properties.put(key, MYSQL_DRIVER_CLASS_NEW);
          }
          if (!keys.isEmpty()) {
              saveProperties(properties, CmsSystemInfo.FILE_PROPERTIES, false, keys);
          }
      }
docs: Updates the JDBC driver class names.<p>
  Needs to be executed before any database access.<p>