如何通过JPA获取保存对象的id？

// 导入相关的JPA和Java EE包

import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.EntityTransaction;
import javax.persistence.Persistence;

// 创建实体类
@Entity
@Table(name = "my_table")
public class MyEntity {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;
    // 其他属性和方法
}

// 在某个方法中使用JPA保存对象并获取id
public void saveEntityAndGetId(MyEntity entity) {
    // 创建EntityManagerFactory
    EntityManagerFactory emf = Persistence.createEntityManagerFactory("myPersistenceUnit");
    // 创建EntityManager
    EntityManager em = emf.createEntityManager();
    // 开启事务
    EntityTransaction tx = em.getTransaction();
    tx.begin();
    // 保存对象
    em.persist(entity);
    // 提交事务
    tx.commit();
    // 获取保存后的id
    Long savedId = entity.getId();
    // 关闭EntityManager和EntityManagerFactory
    em.close();
    emf.close();
}