休眠:生成的ID在sqlIntegrityConstraintVolationException之后保留在非持久实体中

大家好!

一段时间前,我遇到了一个问题:如果存储库的save方法失败,那么由hibernate注入bean的标识符将保留在bean中。这种行为可能会导致我们陷入这样的境地:我们会把不持久的bean想象成持久的bean。我很高兴知道避免这种情况的惯例是什么。

示例测试(Spring引导+Hibernate+Oracle数据库):

@Entity
@SequenceGenerator(name = "TEST_ENTITY_GENERATOR", allocationSize = 1, sequenceName = "TEST_ENTITY_SEQ")
public class TestEntity {
    @Id
    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "TEST_ENTITY_GENERATOR")
    private Long id;

    @Column(nullable = false)
    private String name;

    public Long getId() {
        return id;
    }
}

@Repository
public interface TestEntityRepository extends JpaRepository<TestEntity, Long> {

}


@RunWith(SpringRunner.class)
@SpringBootTest
public class RemainingIdTest {

    @Autowired
    private TestEntityRepository testEntityRepository;

    @Test
    public void test() {
        TestEntity entity = new TestEntity();
        try {
            Assertions.assertThat(entity.getId()).isNull();
            testEntityRepository.save(entity);
            Assertions.fail("Save must fail");
        } catch (DataIntegrityViolationException e) {
            Assertions.assertThat(entity.getId()).isNotNull();
        }
    }
}