code: @Override
      public synchronized String cacheDialect(Dialect dialect) {
          String handle = dialectHandleCache.get(dialect);
          if (handle == null) {
              handle = RandomStringUtils.randomAlphabetic(HANDLE_LENGTH);
              handleDialectCache.put(handle, dialect);
              dialectHandleCache.put(dialect, handle);
          }
          return handle;
      }
docs: {@inheritDoc}