@Entity
@Table(name="auto_devices")
@NamedQuery(name="Device.findAll", query="SELECT d FROM Device d")
public class Device implements Serializable {
    private static final long serialVersionUID = 1L;

    @Id
    @Column(name="adev_id")
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;

    @Column(name="adev_code")
    private BigDecimal code;

    @Column(name="adev_last_config")
    private Timestamp lastConfig;

    @Column(name="adev_model")
    private String model;

    //bi-directional many-to-one association to DeviceType
    @ManyToOne
    @JoinColumn(name="adev_type")
    private DeviceType deviceType;

        // тут всякие геттеры-сеттеры...

    /* Сериализуем как ID */
    @JsonIdentityInfo(generator=ObjectIdGenerators.PropertyGenerator.class, property="id")
    @JsonIdentityReference(alwaysAsId=true)
    public DeviceType getDeviceType() {
        return this.deviceType;
    }

    public void setDeviceType(DeviceType deviceType) {
        this.deviceType = deviceType;
    }

}

@Entity
@Table(name="auto_device_types")
@NamedQuery(name="DeviceType.findAll", query="SELECT d FROM DeviceType d")
public class DeviceType implements Serializable {
    private static final long serialVersionUID = 1L;

    @Id
    @Column(name="adt_id")
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;

    @Column(name="adt_config")
    @Lob
    @Type(type="org.hibernate.type.StringClobType")
    private String config;

    @Column(name="adt_config_time")
    private Timestamp configTime;

    @Column(name="adt_name")
    private String name;

    //bi-directional many-to-one association to Device
    @OneToMany(mappedBy="deviceType", cascade = CascadeType.REMOVE)
    @JsonIgnore
    private List<Device> devices;

    // тут геттеры-сеттеры

}

[{"id":1,"code":1234567890.00,"lastConfig":null,"model":"TR-200","deviceType":1}]

    @RequestMapping(method = RequestMethod.PUT)
    @ResponseStatus(HttpStatus.OK)
    public void update(@RequestBody Device resource) {
        deviceService.update(resource);
    }

{"deviceType":{"id":1}}

 @OneToMany(mappedBy="deviceType", cascade = CascadeType.REMOVE)
    @JsonIgnore
    private List<Device> devices;