Spring JPA REST一对多

问题描述

我希望通过添加来扩展示例 Person 实体的地址列表。所以，我在 @OneToMany 注释中添加了一个地址列表：

I wanted to extend the example Accessing JPA Data with REST by adding an address list to the Person entity. So, I added a list addresses with @OneToMany annotation:

@Entity
public class Person {
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private long id;

    private String firstName;
    private String lastName;

    @OneToMany(fetch = FetchType.EAGER, cascade = CascadeType.ALL)
    private List<Address> addresses = new ArrayList<>();

   // get and set methods...
}

地址类是一个非常简单的类：

The Address class is a very simple one:

@Entity
public class Address {
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private long id;
    private String street;
    private String number;
    // get and set methods...
}

最后我添加 AddressRepository 界面：

public interface AddressRepository extends PagingAndSortingRepository<Address, Long> {}

然后我尝试发布一个有一些地址的人：

Then I tried to POST a person with some addresses:

curl -i -X POST -H "Content-Type:application/json" -d '{  "firstName" : "Frodo",  "lastName" : "Baggins", "addresses": [{"street": "somewhere", "number": 1},{"street": "anywhere", "number": 0}]}' http://localhost:8080/people

我得到的错误是：

Could not read document: Failed to convert from type [java.net.URI] to type [ws.model.Address] for value 'street';
nested exception is java.lang.IllegalArgumentException: Cannot resolve URI street. Is it local or remote? Only local URIs are resolvable. (through reference chain: ws.model.Person[\"addresses\"]->java.util.ArrayList[1]);
nested exception is com.fasterxml.jackson.databind.JsonMappingException: Failed to convert from type [java.net.URI] to type [ws.model.Address] for value 'street'; nested exception is java.lang.IllegalArgumentException: Cannot resolve URI street. Is it local or remote? Only local URIs are resolvable. (through reference chain: ws.model.Person[\"addresses\"]->java.util.ArrayList[1])

创建一对多和多对多关系并将json对象发布给它们的正确方法是什么？

Which is the proper method to create one to many and many to many relationships and post json objects to them?

推荐答案

您应首先发布两个地址，然后使用返回的网址（例如和）在你的人员POST：

You should POST the two addresses first, then use their URLs returned (e.g. http://localhost:8080/addresses/1 and http://localhost:8080/addresses/2) in your Person POST:

curl -i -X POST -H "Content-Type:application/json" -d '{  "firstName" : "Frodo",  "lastName" : "Baggins", "addresses": ["http://localhost:8080/addresses/1","http://localhost:8080/addresses/2"]}' http://localhost:8080/people

如果你想首先保存这个人然后添加它的地址你可以这样做：

If you want to save first the person and then add its addresses you could do this:

curl -i -X POST -H "Content-Type:application/json" -d '{  "firstName" : "Frodo",  "lastName" : "Baggins"}' http://localhost:8080/people
curl -i -X POST -H "Content-Type:application/json" -d '{"street": "somewhere", "number": 1}' http://localhost:8080/addresses
curl -i -X POST -H "Content-Type:application/json" -d '{"street": "anywhere", "number": 0}' http://localhost:8080/addresses
curl -i -X PATCH -H "Content-Type: text/uri-list" -d "http://localhost:8080/addresses/1
http://localhost:8080/addresses/2" http://localhost:8080/people/1/addresses

这篇关于Spring JPA REST一对多的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！