code: public void wait(int retry) {
          long sleepMillis = BACKOFF[Math.min(retry, BACKOFF.length - 1)] * 1000L;
          try {
              Thread.sleep(sleepMillis);
          } catch (InterruptedException ie) {
              Thread.currentThread().interrupt();
              throw new WebbException(ie);
          }
      }
docs: Implementation for the actual wait (depends on the current retry sequence).
  @param retry the retry sequence (starts with 0 for the first retry).