英文:
using jackson instead of DTO in POST mapping?
问题
我有以下的一对多关系：
public class Product {
@Id
@SequenceGenerator(name = "product_id_seq", sequenceName = "product_id_seq")
@GeneratedValue(strategy= GenerationType.SEQUENCE, generator = "product_id_seq")
private Long pid; // 为了处理 Hibernate 的 bug，将其初始化为一个随机值
@Id
@ManyToOne(fetch = FetchType.LAZY)
@JoinColumn(name = "manufacturer", referencedColumnName = "id")
@JsonIdentityInfo(generator = ObjectIdGenerators.PropertyGenerator.class, property = "id")
@JsonIdentityReference(alwaysAsId = true)
private Manufacturer manufacturer;
private String name;
// ......更多的数据成员...
}
以及制造商：
public class Manufacturer {
@Id
@SequenceGenerator(name = "manufacturer_id_seq", sequenceName = "manufacturer_id_seq")
@GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "manufacturer_id_seq")
private Long id;
private String name;
private String country;
@OneToMany(mappedBy = "manufacturer", fetch = FetchType.LAZY, cascade = CascadeType.ALL, orphanRemoval = true)
private List<Product> products;
}
我的 POST 请求主体包含以下的 JSON 数据：
{
"name": "chocolate",
"manufacturer": 2
}
我目前在使用 DTO 和映射函数将 ProductCreationDTO 映射到 Product：
public class ProductCreationDTO {
private String name;
private Long manufacturer;
}
private Product mapProductCreationDTOtoProduct(ProductCreationDTO pcd) {
Product p = modelMapper.map(pcd, Product.class); // 将字段映射到同名的字段（如 manufacturer）
Optional<Manufacturer> o = manufacturerService.getManufacturer(pcd.getManufacturer());
o.ifPresent(m -> p.setManufacturer(m));
return p;
}
我在对象的 GET 调用中通过在 Product 类的制造商对象上添加了以下两个注释来成功进行了这种转换：
@JsonIdentityInfo(generator = ObjectIdGenerators.PropertyGenerator.class, property = "id")
@JsonIdentityReference(alwaysAsId = true)
是否有一种使用 Jackson（注释）的方式来将 POST 请求中的 JSON 映射到产品对象（反序列化），就像在 REST 的 GET 调用中发生的一样（序列化）？
英文:
I have the following one to many relationship :
public class Product {
@Id
@SequenceGenerator(name = "product_id_seq", sequenceName = "product_id_seq")
@GeneratedValue(strategy= GenerationType.SEQUENCE,generator = "product_id_seq")
private Long pid; // initiate it for just a random value in order to hanlde hibernate bug
@Id
@ManyToOne(fetch = FetchType.LAZY)
@JoinColumn(name="manufacturer",referencedColumnName = "id")
@JsonIdentityInfo(generator= ObjectIdGenerators.PropertyGenerator.class, property="id")
@JsonIdentityReference(alwaysAsId=true)
private Manufacturer manufacturer;
private String name;
......more data members...
and manufacturer :
public class Manufacturer {
@Id
@SequenceGenerator(name = "manufacturer_id_seq", sequenceName = "manufacturer_id_seq")
@GeneratedValue(strategy=GenerationType.SEQUENCE,generator = "manufacturer_id_seq")
private Long id;
private String name;
private String country;
@OneToMany(mappedBy = "manufacturer",fetch = FetchType.LAZY,cascade = CascadeType.ALL, orphanRemoval = true)
private List<Product> products;
}
my POST body contain the following json :
{
"name":"chocolate",
"manufacturer": 2,
}
Right now I'm using DTO and mapping function to map the productDTO to a product:
public class ProductCreationDTO {
private String name;
private Long manufacturer;
}
private Product mapProductCreationDTOtoProduct(ProductCreationDTO pcd)
{
Product p = modelMapper.map(pcd,Product.class); // maps fields with same name that arent nested(like manufacturer)
Optional<Manufacturer> o = manufacturerService.getManufacturer(pcd.getManufacturer());
o.ifPresent(m->p.setManufacturer(m));
return p;
}
I suceeded doing this converstion in my get calls for objects by adding those 2 annotations above the manufacturer obj in the Product class:
@JsonIdentityInfo(generator= ObjectIdGenerators.PropertyGenerator.class, property="id")
@JsonIdentityReference(alwaysAsId=true)
Is there a way to using jackson (annotations) to map the post json into a product object (deserialize ) the same it happens during rest get calls(serialize) ?
答案1
得分: 0
以下是翻译好的部分：
所以，我没有使用objectMapper和DTO，而是将我传递的json更改为以下内容：
{
"name": "巧克力",
"manufacturer": {"id": 2}
}
感谢@Lkopo的建议 - 在架构方面，最好创建DTO以传输数据。
带有DTO的完整示例 - https://github.com/marielcherkassky/simple_spring_boot_jpa_project
英文:
So instead of using the objectMapper and the DTO I changed the json that I passed to the following :
{
"name":"chocolate",
"manufacturer": {"id":2}
}
Thanks to @Lkopo for the tip - In aspect of architecture it is better to create DTOs in order to transfer data.
Full example with DTO - https://github.com/marielcherkassky/simple_spring_boot_jpa_project
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