java - 无法使用 JPA 删除实体

Question

我正在尝试使用 JPA 从内存中删除一个实体(目前我不使用 DB)，当我使用 remove 然后尝试找到它显示的已删除实体时 null，但是当我使用 findAll 方法时，它会检索所有数据(已删除实体)...

配置文件.java

@Entity
@Table(name = "profile")
public class Profile {

    @Id
    @GeneratedValue
    private Long id;

    private String nombre;

    private Boolean restrictedAccess;

    private Boolean canValidate;

    // private Set<AccessField> accessFields = new HashSet<AccessField>();

    // private Set<AccessEntity> accessEntities = new HashSet<AccessEntity>();
    @OneToMany(mappedBy = "profile", fetch = FetchType.EAGER)
    private Set<AccessMenu> menuSections = new HashSet<AccessMenu>();

    @OneToMany(mappedBy = "profile", fetch = FetchType.EAGER)
    private Set<User> users = new HashSet<User>();
[getters and setters]

资料库

@Repository
@Transactional
public class ProfileRepository {
    @PersistenceContext
    private EntityManager entityManager;

    public Profile save(Profile p) {
        p = this.entityManager.merge(p);
        this.entityManager.flush();
        return p;
    }

    public void delete(Long id){
        Profile profile = this.entityManager.find(Profile.class, id);
        this.entityManager.remove(profile);
    }

    public List<Profile> findAll() {
        CriteriaQuery cq = this.entityManager.getCriteriaBuilder().createQuery();
        cq.select(cq.from(Profile.class));
        return (List<Profile>) this.entityManager.createQuery(cq).getResultList();
    }

    public Profile findById(Long id){
        return this.entityManager.find(Profile.class, id);
    }
}

Controller 方法

@RequestMapping(value="profile/delete/{idProfile}", method = RequestMethod.GET)
    public String delete(@PathVariable String idProfile,RedirectAttributes ra, Model model){


        profileRepo.delete(Long.valueOf(idProfile));

        model.addAttribute("profiles", profileRepo.findAll());

        return "profile/list";
    }

Answer 1

如果您正尝试通过在 Controller 中使用 Id 来删除实体，请按照 profileRepo.deleteById(Long.valueOf(idProfile)); 进行操作 这个，不是这样的 profileRepo.delete(profileRepo.findById(Long.valueOf(idProfile)));

也可以像这样使用你的存储库函数，

public void deleteArtistById(Long artistId) {
    Artist artist = manager.find(Artist.class, artistId);
    if (artist != null) {
        manager.getTransaction().begin();
        manager.remove(artist);
        manager.getTransaction().commit();
    }
}


public void deleteArtist(Artist artist) {
    manager.getTransaction().begin();
    manager.remove(artist);
    manager.getTransaction().commit();
}

您可以查看此链接了解更多详情: http://kodejava.org/how-do-i-delete-entity-object-in-jpa/