code: private void returnObject(ObjectPool<Classifier> pool, Classifier object) {
          try {
              pool.returnObject(object);
          } catch (Exception e) {
              logger.error("Could not return object to pool", e);
          }
      }
docs: Returns the given object to the pool.
  
  @param pool   The pool to where return the object to.
  @param object The object to be returned to the pool.