Spring数据JPA/Hibernate处理关联

Question

我需要基于参数从实体中检索或不检索一些关联。在下面的示例中，只有在通过api传递参数时，我才需要获取记录列表。你能推荐一种使用hibernate/spring数据实现这一点的方法吗？我正在寻找最干净、最像spring数据的方法。

public class Customer {
  private UUID id;

  @OneToMany(mappedBy = "customer")

  private List<Record> records = new ArrayList<>();
}

public class Record {
    private UUID id;

    @Column(name = "customer_id", length = 36, columnDefinition = "varchar(36)", nullable = false)
    private UUID customerId;
    
    @JoinColumn(name = "customer_id", insertable = false, updatable = false)
    private Customer customer;
}

我的存储库是空的：

public interface CustomerRepository extends JpaRepository<Customer, UUID> {

}

在我的服务中，我做了如下事情：

Customer customer = customerRepository.findById(customerId).orElseThrow(() -> new CustomerNotFoundException("customerId", customerId));

但我想做的是：

if (showRecords) {
    Customer customer = customerRepository.findById(customerId).orElseThrow(() -> new CustomerNotFoundException("customerId", customerId));
} else {
    Customer customer = customerRepository.findByIdWithoutAssociations(customerId).orElseThrow(() -> new CustomerNotFoundException("customerId", customerId));
}

Answer 1

使用基本的findById只返回客户对象，使用另一个方法findWithRecordsById使用@EntityGraph返回客户记录怎么样？

public interface CustomerRepository extends JpaRepository<Customer, UUID>{

    @EntityGraph(attributePaths = {"records"})
    Customer findWithRecordsById(UUID id);
...
}