问事务在将实体从多个一方持久化时被回滚

EN

@Entity 
@Table(name = "student")
public class Student {
    @Id
    @SequenceGenerator(name = "student_pk_generator", sequenceName = 
                              "student_pk_sequence", allocationSize = 1)
    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = 
                               "student_pk_generator")
    @Column(name = "student_id", nullable = false)
    private Long studentId;

    @Column(name = "name", nullable = false)
    private String studentName;

    @OneToMany(mappedBy = "student", cascade = CascadeType.ALL)
    private Set<StudentSubscription> studentSubscription;
}

@Entity
@Table(name = "student_subscription")
@Inheritance(strategy = InheritanceType.JOINED)
public abstract class StudentSubscription {
    @Id
    private Long studentId;

    @ManyToOne(optional = false)
    @JoinColumn(name = "student_id", referencedColumnName = "student_id")
    @MapsId
    private Student student;

    @Column(name = "valid_from")
    private Date validFrom;

    @Column(name = "valid_to")
    private Date validTo;
}

@Entity
@Table(name = "library_subscription", 
       uniqueConstraints = {@UniqueConstraint(columnNames = {"library_code"})})
@PrimaryKeyJoinColumn(name = "student_id")
public class LibrarySubscription extends StudentSubscription {

    @Column(name = "library_code", nullable = false)
    private String libraryCode;

    @PrePersist
    private void generateLibraryCode() {
        this.libraryCode = // some logic to generate unique libraryCode
    }

}

@Entity
@Table(name = "course_subscription", 
       uniqueConstraints = {@UniqueConstraint(columnNames = {"course_code"})})
@PrimaryKeyJoinColumn(name = "student_id")
public class CourseSubscription extends StudentSubscription {

    @Column(name = "course_code", nullable = false)
    private String courseCode;

    @PrePersist
    private void generateCourseCode() {
        this.courseCode = // some logic to generate unique courseCode
    }
}

@Test
public void testLibrarySubscriptionPersist() {
    Student student = studentRepository.findById(100L).get();
    StudentSubscription librarySubscription = new LibrarySubscription();
    librarySubscription.setValidFrom(//some date);
    librarySubscription.setValidTo(//some date);
    librarySubscription.setStudent(student);
    studentSubscriptionRepository.save(librarySubscription);
}

org.springframework.dao.InvalidDataAccessApiUsageException: detached entity passed to persist: com.springboot.data.jpa.entity.Student; nested exception is org.hibernate.PersistentObjectException: detached entity passed to persist: com.springboot.data.jpa.entity.Student

INFO 3515 --- [           main] o.s.t.c.transaction.TransactionContext   : Rolled back transaction for test: [DefaultTestContext@35390ee3 testClass = SpringDataJpaApplicationTests, testInstance = com.springboot.data.jpa.SpringDataJpaApplicationTests@48a12036, testMethod = testLibrarySubscriptionPersist@SpringDataJpaApplicationTests, testException = [null], mergedContextConfiguration = [MergedContextConfiguration@5e01a982 testClass = SpringDataJpaApplicationTests, locations = '{}', classes = '{class com.springboot.data.jpa.SpringDataJpaApplication}', contextInitializerClasses = '[]', activeProfiles = '{}', propertySourceLocations = '{}', propertySourceProperties = '{org.springframework.boot.test.context.SpringBootTestContextBootstrapper=true}', contextCustomizers = set[org.springframework.boot.test.context.filter.ExcludeFilterContextCustomizer@18ece7f4, org.springframework.boot.test.json.DuplicateJsonObjectContextCustomizerFactory$DuplicateJsonObjectContextCustomizer@264f218, org.springframework.boot.test.mock.mockito.MockitoContextCustomizer@0, org.springframework.boot.test.web.client.TestRestTemplateContextCustomizer@2462cb01, org.springframework.boot.test.autoconfigure.actuate.metrics.MetricsExportContextCustomizerFactory$DisableMetricExportContextCustomizer@928763c, org.springframework.boot.test.autoconfigure.properties.PropertyMappingContextCustomizer@0, org.springframework.boot.test.autoconfigure.web.servlet.WebDriverContextCustomizerFactory$Customizer@7c3fdb62, org.springframework.boot.test.context.SpringBootTestArgs@1, org.springframework.boot.test.context.SpringBootTestWebEnvironment@1ad282e0], contextLoader = 'org.springframework.boot.test.context.SpringBootContextLoader', parent = [null]], attributes = map['org.springframework.test.context.event.ApplicationEventsTestExecutionListener.recordApplicationEvents' -> false]]