code: @Override
      public long getNumberOfEvents() {
          try {
              lock.readLock().lock();
              long currentTime = System.currentTimeMillis();
              actualizeCounts(currentTime);
              return sumCounts();
          } finally {
              lock.readLock().unlock();
          }
      }
docs: This method returns total number of events happened withing predefined timeframe
  
  @return