@ManyToOne关系PK未插入

Question

我有一个应用程序（Spring 4 MVC + Hibernate 4 + MySQL + Maven集成示例使用注释），将Spring与Hibernate结合使用基于注释的配置。 我有这样的域对象：

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

    enum Type { 
     IOS, 
     ANDROID 
    } 



    public Device() { 
     super(); 
    } 

    public Device(String key) { 
     super(); 
     this.key = key; 
    } 

    @Id 
    @GeneratedValue(strategy = GenerationType.IDENTITY) 
    private int id; 

    @NotEmpty 
    @Size(min=1, max=50) 
    @Column(name = "device_key", unique=true, nullable = false) 
    private String key; 


    @Column(name = "device_desc") 
    private String desc; 

    @Enumerated(EnumType.STRING) 
    @Column(name = "device_type") 
    private Type type; 


    @OneToOne(fetch=FetchType.EAGER) 
    @JoinColumn(name = "application_id", 
       referencedColumnName = "id") 
    private Application application; 


    public int getId() { 
     return id; 
    } 

    public void setId(int id) { 
     this.id = id; 
    } 

    public String getKey() { 
     return key; 
    } 

    public void setKey(String key) { 
     this.key = key; 
    } 

    public String getDesc() { 
     return desc; 
    } 

    public void setDesc(String desc) { 
     this.desc = desc; 
    } 

    public Application getApplication() { 
     return application; 
    } 

    public void setApplication(Application application) { 
     this.application = application; 
    } 

    @Override 
    public int hashCode() { 
     final int prime = 31; 
     int result = 1; 
     result = prime * result + ((desc == null) ? 0 : desc.hashCode()); 
     result = prime * result + id; 
     result = prime * result + ((key == null) ? 0 : key.hashCode()); 
     return result; 
    } 

    @Override 
    public boolean equals(Object obj) { 
     if (this == obj) 
      return true; 
     if (obj == null) 
      return false; 
     if (getClass() != obj.getClass()) 
      return false; 
     Device other = (Device) obj; 
     if (desc == null) { 
      if (other.desc != null) 
       return false; 
     } else if (!desc.equals(other.desc)) 
      return false; 
     if (id != other.id) 
      return false; 
     if (key == null) { 
      if (other.key != null) 
       return false; 
     } else if (!key.equals(other.key)) 
      return false; 
     return true; 
    } 

    @Override 
    public String toString() { 
     return "Device [id=" + id + ", key=" + key + ", desc=" + desc + "]"; 
    } 
} 

链接到这个其它之一：

@Entity 
@Table(name="t_device_event") 
public class DeviceEvent { 

    public class Coordinates { 

     @Column(name = "device_lat") 
     private Double lat; 

     @Column(name = "device_lng") 
     private Double lng; 


     public Coordinates(Double lat, Double lng) { 
      super(); 
      this.lat = lat; 
      this.lng = lng; 
     } 

     public Double getLat() { 
      return lat; 
     } 

     public void setLat(Double lat) { 
      this.lat = lat; 
     } 

     public Double getLng() { 
      return lng; 
     } 

     public void setLng(Double lng) { 
      this.lng = lng; 
     } 

    } 

    @Id 
    @GeneratedValue(strategy = GenerationType.IDENTITY) 
    private int id; 

    @ManyToOne 
    private Device device; 

    private Long received; 

    private String message; 

    @Transient 
    private Coordinates coordinates; 


    public Coordinates getCoordinates() { 
     return coordinates; 
    } 

    public void setCoordinates(Coordinates coordinates) { 
     this.coordinates = coordinates; 
    } 

    public int getId() { 
     return id; 
    } 

    public void setId(int id) { 
     this.id = id; 
    } 

    public Device getDevice() { 
     return device; 
    } 

    public void setDevice(Device device) { 
     this.device = device; 
    } 

    public Long getReceived() { 
     return received; 
    } 

    public void setReceived(Long received) { 
     this.received = received; 
    } 

    public String getMessage() { 
     return message; 
    } 

    public void setMessage(String message) { 
     this.message = message; 
    } 

    public DeviceEvent(Device device) { 
     super(); 
     this.device = device; 
    } 
} 

和这段代码在控制器：

Device device = deviceService.findByKey("AS3989E506"); 

    DeviceEvent deviceEvent = new DeviceEvent(device); 
    deviceEvent.setCoordinates(deviceEvent.new Coordinates(Double.MIN_VALUE, Double.MAX_VALUE)); 
    deviceEvent.setMessage("message"); 
    deviceEvent.setReceived(new Date().getTime()); 

    deviceEventService.save(deviceEvent); 

和休眠控制台：

休眠：

个

select 
     this_.id as id1_1_1_, 
     this_.application_id as applicat5_1_1_, 
     this_.device_desc as device_d2_1_1_, 
     this_.device_key as device_k3_1_1_, 
     this_.device_type as device_t4_1_1_, 
     applicatio2_.id as id1_0_0_, 
     applicatio2_.application_desc as applicat2_0_0_, 
     applicatio2_.application_key as applicat3_0_0_ 
    from 
     t_device this_ 
    left outer join 
     t_application applicatio2_ 
      on this_.application_id=applicatio2_.id 
    where 
     this_.device_key=? 
Hibernate: 
    insert 
    into 
     t_device_event 
     (device_id, message, received) 
    values 
     (?, ?, ?) 
Hibernate: 
    select 
     this_.id as id1_1_1_, 
     this_.application_id as applicat5_1_1_, 
     this_.device_desc as device_d2_1_1_, 
     this_.device_key as device_k3_1_1_, 
     this_.device_type as device_t4_1_1_, 
     applicatio2_.id as id1_0_0_, 
     applicatio2_.application_desc as applicat2_0_0_, 
     applicatio2_.application_key as applicat3_0_0_ 
    from 
     t_device this_ 
    left outer join 
     t_application applicatio2_ 
      on this_.application_id=applicatio2_.id 

这里的服务：

@Service("deviceEventService") 
@Transactional 
public class DeviceEventServiceImpl implements DeviceEventService { 

    @Autowired 
    private DeviceEventDao dao; 


    public void save(DeviceEvent deviceEvent) { 
     dao.save(deviceEvent);  
    } 

} 

其他

：

@Service("deviceService") 
@Transactional 
public class DeviceServiceImpl implements DeviceService { 

    @Autowired 
    private DeviceDao dao; 

    public Device findById(int id) { 
     return dao.findById(id); 
    } 


    public void save(Device device) { 
     dao.save(device); 
    } 


    public void update(Device device) { 
     // TODO Auto-generated method stub 

    } 


    public void delete(Device device) { 
     // TODO Auto-generated method stub 
    } 


    public List<Device> findAll() { 
     return dao.findAll(); 
    } 


    public Device findByKey(String key) { 
     return dao.findByKey(key); 
    } 


    public boolean isDeviceKeyUnique(Integer id, String key) { 
     Device device = findByKey(key); 
     return (device == null || ((id != null) && (device.getId() == id))); 
    } 


    public void deleteByKey(String key) { 
     dao.deleteByKey (key); 
    } 



} 

但现场DEVICE_ID表的t_device_event为空！

Answer 1

可能@JoinColumn注释将帮助您

@ManyToOne 
@JoinColumn(name="device_id") 
private Device device;