将NativeQuery映射到POJO

Question

我有一个要映射到POJO的NativeQuery。

我尝试了下面的方法，但它以无限循环结束。

public synchronized List<FreeIP> getFirstFreeHost() {
    String q = "SELECT i.subnet, h.ip_host FROM ip_addresses i join hosts h on i.id = h.ip_addresses_id ORDER BY i.subnet, h.ip_host";
    this.entityManager = this.entityManagerFactory.createEntityManager();
    Query query = this.entityManager.createNativeQuery(q);
    List<Object[]> rows = query.getResultList();
    List<FreeIP> result = new ArrayList<>();
    for (Object[] row : rows) {
        result.add(new FreeIP((String) row[0], (String) row[1]));
    }

    return result;
}

Answer 1

看看QLRM：https://github.com/simasch/qlrm

然后您可以执行以下操作：

JpaResultMapper jpaResultMapper = new JpaResultMapper();

Query q = em.createNativeQuery("SELECT i.subnet, h.ip_host FROM ip_addresses i join hosts h on i.id = h.ip_addresses_id ORDER BY i.subnet, h.ip_host");

List<EmployeeTO> list = jpaResultMapper.list(q, FreeIP.class);

确保FreeIP有一个接受查询的所有参数的构造函数。