code: private int getBatchSize(String persistenceUnit, Map<String, Object> puProperties)
      {
          String batch_size = puProperties != null ? (String) puProperties.get(PersistenceProperties.KUNDERA_BATCH_SIZE)
                  : null;
          return batch_size != null ? Integer.valueOf(batch_size) : KunderaMetadataManager.getPersistenceUnitMetadata(
                  kunderaMetadata, persistenceUnit).getBatchSize();
      }
docs: Gets the batch size.
  
  @param persistenceUnit
  the persistence unit
  @param puProperties
  the pu properties
  @return the batch size