Hibernate错误消息:刷新前保存临时实例

Session session = sessionFactory.openSession();
Transaction tx = session.beginTransaction();

MyEntity entity = new MyEntity();
entity.setName("example");
session.save(entity); // 确保实例已持久化

tx.commit();

// 现在可以安全地刷新实例
session.refresh(entity);

Session session = sessionFactory.openSession();
Transaction tx = session.beginTransaction();

MyEntity entity = new MyEntity();
entity.setName("example");
session.merge(entity); // 合并实例状态

tx.commit();

// 现在可以安全地刷新实例
session.refresh(entity);

Session session = sessionFactory.openSession();
Transaction tx = session.beginTransaction();

MyEntity entity = new MyEntity();
entity.setName("example");
session.save(entity);

// 使用悲观锁
Query query = session.createQuery("from MyEntity where id = :id");
query.setParameter("id", entity.getId());
query.setLockMode(LockMode.PESSIMISTIC_WRITE);
MyEntity lockedEntity = (MyEntity) query.uniqueResult();

tx.commit();

// 现在可以安全地刷新实例
session.refresh(lockedEntity);