我有两个实体：用户和设备.每个设备应该有一个用户.但用户已经存在，所以我想通过ID链接到我的设备的用户.目前，我必须创建一个用户，并将其作为后请求发送到我的后端.但我只想发送应该存储的ID.
我已经创建了一个应用程序，必须通过JSON文件传输数据

@Entity
@Table(name = "Users")
public class User {
    @Id
    @GeneratedValue (strategy = GenerationType.IDENTITY)
    private Long id;
    private String name;
    private String email;
    private String password;
    private boolean activity;
    private boolean login;

Entity
@Table(name = "Devices")
public class Device {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id
    private boolean activity;
    private String location;
    @OneToOne
    @JoinColumn(name = "UserId", referencedColumnName = "id")
    private User owner;

//This is the JSON-File how I have to send it
{
    "activity": "true",
    "location": "Room 102",
    "owner": {
        "name": "Mike",
        "email": "testMail@test.com",
        "password": "123456",
        "activity": "true",
        "login": "false"
    }
}

//This is how I would like to send it (Only sending the Id of the other Table)
{
    "activity": "true",
    "location": "Room 102",
    "owner": "1"
}

我试过通过关系（多对一和一对多），但它没有工作。