How to use

hasPrevious

method

in

org.springframework.data.domain.Pageable

public boolean hasPrevious() {
  return delegate.hasPrevious();
}

public boolean hasPrevious() {
  return delegate.hasPrevious();
}

/**
 * Calculate total mount.
 * @return if return -1 means can not judge ,need count from database.
 */
protected <X> long calculateTotal(Pageable pager, List<X> result) {
  if (pager.hasPrevious()) {
    if (CollectionUtils.isEmpty(result)) {
      return -1;
    }
    if (result.size() == pager.getPageSize()) {
      return -1;
    }
    return (pager.getPageNumber() - 1) * pager.getPageSize() + result.size();
  }
  if (result.size() < pager.getPageSize()) {
    return result.size();
  }
  return -1;
}