未记录 DTO 参考类，创建后为“空”答案

【问题标题】：DTO Reference Class not recorded, 'null' after create未记录 DTO 参考类，创建后为“空”
【发布时间】：2017-06-17 03:40:21
【问题描述】：

我有一个名为 RoomDetailDto 的 DTO 类，如下所示

public class RoomDetailDto {

String ID;

@NotEmpty
String cd;

@NotEmpty
String name;

String dscp;


RoomCategoryDto roomCategoryDto;

//setter and getter

roomCategoryDto 引用了另一个名为 RoomCategoryDto 的 DTO，如下所示：

public class RoomCategoryDto {

String ID;

@NotEmpty
@Length(min = 0, max = 5)
String cd;

@NotEmpty
String name;

@NotEmpty
@NumberValue
String cost;

String dscp;

//setter and getter

我发送到服务器的这个 JSON

{ "cd":"dfs23", “名称”：“df223”， "dscp":"sfdsfs", "roomCategoryDto":{ "cd":"KLS2", "name":"Kelas 2", “成本”：“200000”， “dscp”：空， “id”：“7f554d7a-3c5d-4c15-921d-fa4b4c629e6c” } }

发送到服务器后，该记录成功插入，但我的 roomCategoryDto 是 'NULL'

{ "cd": "dfs23", “名称”：“df223”， “dscp”：“sfdsfs”， “roomCategoryDto”：空， “id”：“ed22b38d-2bc3-4c80-b035-8936318c90c7” }

谁能给点建议？请在下面找到我的控制器：

@RequestMapping(value = "/updateAction", method = RequestMethod.POST, produces = MediaType.APPLICATION_JSON_VALUE)
@ResponseBody
public RoomDetailDto update(@Validated @RequestBody RoomDetailDto data) throws ParseException, RecordNotFoundException, java.text.ParseException {
    logger.info("add");
    RoomDetailEntity add = roomDetailService.updateRoomDetail(convertToEntity(data));
    return convertToDto(add);

}

和我的实体如下

@Entity(name = "RoomCategoryEntity") @Table(name = "t_room_category") public class RoomCategoryEntity implements Serializable {

public static final long serialVersionUID = 1L;

@Id
@GeneratedValue(generator = "uuid")
@GenericGenerator(name = "uuid", strategy = "uuid2")
@Column(name = "ID", unique = true)
private String ID;

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

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

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

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

@Column(name = "createDate")
private Date createDate;

@Column(name = "updateDate")
private Date updateDate;

@Column(name = "isDel")
private Date isDel; //setter and getter}

================================================ ====================

@Entity(name = "RoomDetailEntity") @Table(name = "t_room_details") public class RoomDetailEntity implements Serializable {
public static final long serialVersionUID = 1L;

@Id
@GeneratedValue(generator = "uuid")
@GenericGenerator(name = "uuid", strategy = "uuid2")
@Column(name = "ID", unique = true)
private String ID;

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

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

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

@ManyToOne(fetch = FetchType.EAGER)
@JoinColumn(name = "room_category_id", referencedColumnName = "ID")
private RoomCategoryEntity roomCategoryEntity;

@Column(name = "createDate")
private Date createDate;

@Column(name = "updateDate")
private Date updateDate;

@Column(name = "isDel")
private Date isDel;

【问题讨论】：

标签： java json spring rest dto

【解决方案1】：

我只是尝试将引用表更改为实体，并成功插入

public class RoomDetailDto {

String ID;

@NotEmpty
String cd;

@NotEmpty
String name;

String dscp;

// I change below line
RoomCategoryEntity roomCategoryEntity;

[ { "cd": "df23", “名称”：“df23”， “dscp”：“sfdsfs”， “房间类别实体”：{ "cd": "KLS2", "name": "Kelas 2", “成本”：“200000”， “dscp”：空， “创建日期”：1497535268000， “更新日期”：空， “isDel”：空， “id”：“7f554d7a-3c5d-4c15-921d-fa4b4c629e6c” }, “id”：“02c28356-9783-46a7-8ac5-9e00497d9be2” } ]

【讨论】：