How to use

getCountQuery

method

in

org.springframework.data.jpa.repository.support.SimpleJpaRepository

/**
 * Creates a new count query for the given {@link Specification}.
 *
 * @param spec can be {@literal null}.
 * @return
 * @deprecated override {@link #getCountQuery(Specification, Class)} instead
 */
@Deprecated
protected TypedQuery<Long> getCountQuery(@Nullable Specification<T> spec) {
  return getCountQuery(spec, getDomainClass());
}

@Override
public long count(@Nullable Specification<T> spec) {
  return executeCountQuery(getCountQuery(spec, getDomainClass()));
}

@Override
public <S extends T> long count(Example<S> example) {
  return executeCountQuery(getCountQuery(new ExampleSpecification<S>(example), example.getProbeType()));
}

/**
 * Reads the given {@link TypedQuery} into a {@link Page} applying the given {@link Pageable} and
 * {@link Specification}.
 *
 * @param query must not be {@literal null}.
 * @param domainClass must not be {@literal null}.
 * @param spec can be {@literal null}.
 * @param pageable can be {@literal null}.
 * @return
 */
protected <S extends T> Page<S> readPage(TypedQuery<S> query, final Class<S> domainClass, Pageable pageable,
    @Nullable Specification<S> spec) {
  if (pageable.isPaged()) {
    query.setFirstResult((int) pageable.getOffset());
    query.setMaxResults(pageable.getPageSize());
  }
  return PageableExecutionUtils.getPage(query.getResultList(), pageable,
      () -> executeCountQuery(getCountQuery(spec, domainClass)));
}

/**
 * Creates a new count query for the given {@link Specification}.
 *
 * @param spec can be {@literal null}.
 * @return
 * @deprecated override {@link #getCountQuery(Specification, Class)} instead
 */
@Deprecated
protected TypedQuery<Long> getCountQuery(@Nullable Specification<T> spec) {
  return getCountQuery(spec, getDomainClass());
}

public long count(@Nullable Specification<T> spec) {
  return executeCountQuery(getCountQuery(spec, getDomainClass()));
}

@Override
@SuppressWarnings("unchecked")
protected <S extends T> TypedQuery<Long> getCountQuery(Specification<S> spec,
  Class<S> domainClass) {
 return super.getCountQuery(((Specifications<S>)aclJpaSpec()).and(spec), domainClass);
}

@Override
public <S extends T> long count(Example<S> example) {
  return executeCountQuery(getCountQuery(new ExampleSpecification<S>(example), example.getProbeType()));
}

/**
 * Reads the given {@link TypedQuery} into a {@link Page} applying the given {@link Pageable} and
 * {@link Specification}.
 *
 * @param query must not be {@literal null}.
 * @param domainClass must not be {@literal null}.
 * @param spec can be {@literal null}.
 * @param pageable can be {@literal null}.
 * @return
 */
protected <S extends T> Page<S> readPage(TypedQuery<S> query, final Class<S> domainClass, Pageable pageable,
    @Nullable Specification<S> spec) {
  if (pageable.isPaged()) {
    query.setFirstResult((int) pageable.getOffset());
    query.setMaxResults(pageable.getPageSize());
  }
  return PageableExecutionUtils.getPage(query.getResultList(), pageable,
      () -> executeCountQuery(getCountQuery(spec, domainClass)));
}