小编ara*_*mal的帖子

我正在测试Spring Data 1.10.4.RELEASE,遵循Spring Data Docs中的示例http://docs.spring.io/spring-data/jpa/docs/current/reference/html/#projections

我注意到一些问题,我有两个问题.

首先让我假设我有这两个实体:

@Entity
public class Person {

  @Id @GeneratedValue
  private Long id;
  private String firstName, lastName;

  @OneToOne
  private Address address;
}

@Entity
public class Address {

  @Id @GeneratedValue
  private Long id;
  private String street, state, country;
}

• 问题1:

对于以下预测:

interface PersonLimited {  

  String getFirstName(); 

  AddressLimited getAddress();
}

interface AddressLimited {  

  String getCountry(); 
}

当我运行findPersonByFirstNameProjectedForLimitedData时

interface PersonRepository extends CrudRepository<Person, Long> {

  @Query("select p from Person p where p.firstName = ?1")
  PersonLimited findPersonByFirstNameProjectedForLimitedData(String firstName);
} …