Question

如何使用属性表达式编写JPA存储库方法，以检查列表中是否存在多个项目或这些项目的属性？我可以在列表中查找单个项目，请参阅下面的邮政编码，但我试图编写一种检查多个邮政编码的方法，其中结果集中的每个人在其地址列表中都有两个邮政编码。

@Repository
public interface PersonRepository extends CrudRepository<Person, Long> {
    // Works
    Set<Person> findAllByAddresses_ZipCode(String zip);

    // Doesn't work - does not return expected results
    Set<Person> findAllByAddresses_ZipCode_And_Addresses_ZipCode(String zip1, String zip2);
}

我目前的hack是为2个邮政编码取两套，然后找到两套的交集：

public @ResponseBody
    Iterable<Person> personsWithBothZipCodes(@PathVariable("zip1") String zip1,
                                             @PathVariable("zip2") String zip2) {

    Set<Person> a = personRepository.findAllByAddresses_ZipCode(zip1);
    Set<Person> b = personRepository.findAllByAddresses_ZipCode(zip2);

    // Only return results that contain both zip1 and zip2.
    a.retainAll(b);

    return a;
}

该实体如下所示：

@Entity
public class Person
{
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Long id;

    // zipcode is a String property on an Address.
    @OneToMany(targetEntity = com.data.Address.class, fetch = FetchType.EAGER, cascade = CascadeType.ALL)
    private List<Address> addresses = new ArrayList<Address>();
    ...
}

有没有办法把它写成方法标题的一部分？ Relevant docs

Answer 1

是的，只需在查询中添加In字样

即可

Set<Person> findAllByAddresses_ZipCodeIn(Set<String> zip);

然后在您的控制器中，您可以执行以下操作：

public @ResponseBody Iterable<Person> personsWithBothZipCodes(@PathVariable("zip1") String zip1, @PathVariable("zip2") String zip2) {

    Set<String> zipSet = new HashSet<>();
    zipSet.add(zip1);
    zipSet.add(zip2);

    Set<Person> a = personRepository.findAllByAddresses_ZipCodeIn(zipSet);

    return a;
}

不知道这是否有效，但可以尝试

Set<Person> findAllByAddresses_ZipCodeInAndZipCodeIn(Set<String> zip1, Set<String> zip2);

public @ResponseBody Iterable<Person> personsWithBothZipCodes(@PathVariable("zip1") String zip1, @PathVariable("zip2") String zip2) {

    Set<String> zipSet1 = new HashSet<>();
    zipSet1.add(zip1);

    Set<String> zipSet2 = new HashSet<>();
    zipSet2.add(zip2);

    Set<Person> a = personRepository.findAllByAddresses_ZipCodeInAndZipCodeIn(zipSet1, zipSet2);

    return a;
}

Answer 2

也许您可以使用JPQL查询（如评论中所示）？

@Query("from Person as person" +
" join person.addresses as address1 with address1.zipCode = ?1" +
" join person.addresses as address2 with address2.zipCode = ?2")
Set<Person> findByZipCodes(String zipCode1, String zipCode2);

没有真正复制你的案子，但它应该可行。

Spring JPA属性表达式通过列表中项目的交集查找

2 个答案: