java - Spring 数据存储库 : Detached entity passed to persist

Question

配置文件对象有一个任务列表。保存新配置文件时，任务列表也应与数据库同步(插入 或更新)。问题是 profile-repository 的 save()-method 只允许一个或另一个方法取决于属性上方的级联属性集(CascadeType.PERSIST 或 MERGE) .

配置文件类

@Entity
@Inheritance(strategy = InheritanceType.SINGLE_TABLE)
public abstract class AbstractProfile implements Profile {
    ...

    @OneToMany(fetch = FetchType.EAGER, cascade = CascadeType.PERSIST)
    private List<Task> tasks;

    ..

JUnit-测试类

public class ProfileTaskRepositoryTest {

    @Autowired 
    private ProfileRepository profileRepo;    //extends JpaRepository
    @Autowired
    private TaskRepository taskRepo;          //extends JpaRepository

    @Test // ->this test passes
    public void testCreateProfileWithNewTask() {

        //profileData and taskData hold dummy data. They return new objects
        AbstractProfile interview = profileData.createITInterviewProfile();
        Task questionTask = taskData.createInterviewQuestionTask();

        //add new task to profile and save
        interview.addTask(questionTask);
        profileRepo.save(interview);

        //task repository confirms the insertion
        assertTrue(taskRepo.count() == 1); 
    }

    @Test // ->this test fails
    public void testCreateProfileWithExistingTask() {

        //first create task and save in DB
        Task questionTask = taskData.createInterviewQuestionTask();  // transient obj
        taskRepo.save(questionTask);  // questionTask becomes detached

        // then create a new profile and add the existing task.
        // the problem is the existing task is now detached)
        AbstractProfile interview = profileData.createITInterviewProfile();
        interview.addTask(questionTask);

        profileRepo.save(interview); // !!! this throws an exception
    }

我假设 questionTask-object 在 taskRepo 将它保存在 DB 中然后关闭 session 时分离。

异常(exception):

org.springframework.orm.jpa.JpaSystemException: org.hibernate.PersistentObjectException: detached entity passed to persist: *.Task; nested exception is javax.persistence.PersistenceException: org.hibernate.PersistentObjectException: detached entity passed to persist: *.Task
...

profileRepo.save() 应该能够处理任务列表的插入 和更新。有什么优雅的方法可以解决这个问题吗？

Answer 1

您应该在测试类上放置@Transactional 属性以避免异常。

@Transactional
@TransactionConfiguration
public class ProfileTaskRepositoryTest {
}

希望这对您有所帮助。