Java OptimisticLockingFailureException:批更新返回意外的行计数

在SpringWebMVC应用程序中，我有一个简单的父-子-一对多单向关系。我有两个RESTful api：POST和PUT

母公司：

@Entity
@EqualsAndHashCode(exclude = {"children", "id"})
public class Parent {

    @Id
    @Column
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;

    private String name;

    @OneToMany(fetch = FetchType.LAZY, cascade = CascadeType.ALL, orphanRemoval = true)
    @JoinColumn(name = "PARENT_ID", nullable = false, updatable = false)
    private Set<Child> children = new HashSet<>();
}

控制器：

@RestController
@RequestMapping("/parent")
public class Controller {

    @Autowired
    private ServiceImpl serviceImpl;

    @PostMapping
    public ResponseEntity<Parent> post(@RequestBody final Parent parent) {
        return new ResponseEntity<Parent>(serviceImpl.create(parent), HttpStatus.OK);
    }

    @PutMapping
    public ResponseEntity<Parent> put(@RequestBody final Parent parent) {
        return new ResponseEntity<Parent>(serviceImpl.update(parent), HttpStatus.OK);
    }
}

我有一个父级存储库。 作为POST api的一部分，我一起创建父级和子级

我需要通过PUT更新家长和孩子。 但是，当我尝试替换已创建父项的一个或多个子项时，我会收到错误：

{"timestamp":"2019-05-27T20:21:53.451+0000","status":500,"error":"Internal Server Error","message":"Batch update returned unexpected row count from update [0]; actual row count: 0; expected: 1; nested exception is org.hibernate.StaleStateException: Batch update returned unexpected row count from update [0]; actual row count: 0; expected: 1","path":"/parent"}

只有在使用多个线程执行简单的JMETER perf测试时，才会出现此问题

---

如果我将CascadeType更改为在关系的父端合并，则更新工作正常，但新实体的持久性将通过Post api失败。

存在乐观锁定，以防止一行被多个事务更新。您是否试图通过Jmeter多次更新同一记录？

@Service
public class ServiceImpl implements inter {
    @Autowired
    ParentRepository repository;

    public Parent create(Parent parent) {
        return repository.save(parent);
    }

    @Transactional(readOnly = true)
    public Parent findById(Long id) {
        return repository.findById(id).orElseThrow(IllegalArgumentException::new);
    }

    @Transactional
    public Parent update(Parent toUpdate) {
        Parent retrieved = this.findById(toUpdate.getId());

        retrieved.getChildren().retainAll(toUpdate.getChildren());
        retrieved.getChildren().addAll(toUpdate.getChildren());

        return repository.save(retrieved);
    }
}

{"timestamp":"2019-05-27T20:21:53.451+0000","status":500,"error":"Internal Server Error","message":"Batch update returned unexpected row count from update [0]; actual row count: 0; expected: 1; nested exception is org.hibernate.StaleStateException: Batch update returned unexpected row count from update [0]; actual row count: 0; expected: 1","path":"/parent"}