与@MapsId双向@OneToOne级联

如何解决与@MapsId双向@OneToOne级联

我使用弹簧靴2.1.1.RELEASE，休眠5.3.7.FINAL

规则是，用户不能有电话（phone在user中可以为空，但是，电话不能在没有用户的情况下存在（user在{{1中不能为空） }}。

实体：

phone

控制器：

@Entity
public class Phone {
    
   @Id
   private Long id;
    
   @OneToOne
   @MapsId
   @JoinColumn(name = "id")
   private User user;
    
   public Long getId() {
       return id;
   }
   public void setId(final Long id) {
       this.id = id;
   }
    
   public User getUser() {
      return user;
   }
   public void setUser(final User user) {
      this.user = user;
   }
}
        
@Entity
public class User {

   @Id
   @GeneratedValue(strategy = GenerationType.IDENTITY)
   private Long id;
    
   @OneToOne(mappedBy = "user",cascade = CascadeType.ALL,orphanRemoval = true)
   private Phone phone;
    
   public Long getId() {
       return id;
   }
   public void setId(final Long id) {
       this.id = id;
   }
    
   public Phone getPhone() {
       return phone;
   }
   public void setPhone(final Phone phone) {
       this.phone = phone;
   }
}

存储库：

@RestController
@RequestMapping
public class UserController {
    
   private final UserService userService;
    
   public UserController(final UserService userService) {
       this.userService = userService;
   }
    
   @GetMapping("/demo")
   public void createUserAndAddPhone() {
       final User user = new User();
       userService.save(user);
       final Phone phone = new Phone();
    
       phone.setUser(user);
       user.setPhone(phone);
       userService.update(user);
   }
}

服务：

public interface UserRepository  extends PagingAndSortingRepository<User,Long> {
}

表格：

@Service
public class UserService {
    
   private final UserRepository userRepository;
    
   public UserService(final UserRepository userRepository) {
       this.userRepository = userRepository;
   }
    
   @Transactional
   public void save(final User user) {
       userRepository.save(user);
   }
    
   @Transactional
   public void update(final User user) {
       userRepository.save(user);
   }
}

应用yml：

CREATE TABLE `phone` (
   `id` bigint(20) NOT NULL,PRIMARY KEY (`id`)
);
    
CREATE TABLE `user` (
   `id` bigint(20) NOT NULL AUTO_INCREMENT,PRIMARY KEY (`id`)
)

pom xml：

spring:
   datasource:
      url: jdbc:mysql://localhost:3308/demo?characterEncoding=utf8&useSSL=false&serverTimezone=UTC&useLegacyDatetimeCode=false&allowPublicKeyRetrieval=true
      username: root
      password: 123456
      driver-class-name: com.mysql.jdbc.Driver
   jpa:
      database-platform: org.hibernate.dialect.MySQL5Dialect
      hibernate:
         ddl-auto: validate

致电<?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.1.1.RELEASE</version> <relativePath/> <!-- lookup parent from repository --> </parent> <groupId>com.example</groupId> <artifactId>demo</artifactId> <version>0.0.1-SNAPSHOT</version> <name>demo</name> <description>Demo project for Spring Boot</description> <properties> <java.version>1.8</java.version> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-jpa</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>com.google.code.findbugs</groupId> <artifactId>jsr305</artifactId> <version>2.0.1</version> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>5.1.46</version> <scope>runtime</scope> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> </project> 给我一个错误：

org.hibernate.id.IdentifierGenerationException：尝试分配ID 来自空的一对一属性[com.example.demo.Phone.user]

当我注释GET http://localhost:8080/demo时，它可以工作并生成：

userService.save(user);

但是如果insert into `user` values ( ) -- Generated identifier: 13,using strategy: org.hibernate.id.ForeignGenerator insert into `phone` (`id`) values (?) -- Binding parameter [1] as [BIGINT] - [13] 一直存在并随后进行了更新，则它不起作用（引发上述异常）

解决方法

啊，最后，这是一个休眠错误（HHH-12436）。

它可以通过以下用例在纯休眠应用程序中重现：

Session session = sessionFactory.openSession();

Transaction tr1 = session.beginTransaction();
User user = new User();
session.persist(user);
tr1.commit();

Transaction tr2 = session.beginTransaction();
Phone newPhone = new Phone();
user.setPhone(newPhone);
newPhone.setUser(user);
session.merge(user);
tr2.commit();

session.close();

从上面的链接中可以看到，它已在hibernate 5.4分支中修复。

P.S。我能够在最新的5.3版本（5.3.18.Final）中重现该问题