1.持久层继承JpaSpecificationExecutor

@Repository
public interface DailyBillingRepository extends PagingAndSortingRepository<DailyBilling, Long>, JpaSpecificationExecutor<DailyBilling> {}
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2.JpaSpecificationExecutor 提供的方法：

public interface JpaSpecificationExecutor<T> {T findOne(Specification<T> spec);List<T> findAll(Specification<T> spec);Page<T> findAll(Specification<T> spec, Pageable pageable);List<T> findAll(Specification<T> spec, Sort sort);long count(Specification<T> spec);
}
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调用 ：

 public Page<DailyBilling> getList(Integer page, Integer rows,String beginTime,String endTime,String result){//Specification创建动态sql//Root<ExportSubsidyPersonnel> root, CriteriaQuery<?> criteriaQuery, CriteriaBuilder criteriaBuilderSpecification<DailyBilling> specification= (root, query, cb) -> {Predicate predicate = cb.conjunction();if (StringHelper.isNotBlank(beginTime) && StringHelper.isNotBlank(endTime)){// sql ==》 billData between beginTime and endTimepredicate.getExpressions().add(cb.between(root.<Date>get("billData"), DateHelper.getDate(beginTime), DateHelper.getDate(endTime)));}if (StringHelper.isNotBlank(result) && !result.equals("2")){// sql ==》 differenceAmount = 0  或者 differenceAmount <> 0Predicate p = null;if ("1".equals(result)){p = cb.equal(root.<BigDecimal>get("differenceAmount"),BigDecimal.ZERO);}if ("0".equals(result)){p = cb.notEqual(root.<BigDecimal>get("differenceAmount"),BigDecimal.ZERO);}predicate.getExpressions().add(p);}return predicate;};return dailyBillingRepository.findAll(specification,new PageRequest(page,rows));}
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CriteriaBuilder接口提供了操作sql的基本语句，可直接调用。