Question

我有两个实体，分别通过@OnToOne关系连接到父级和子级：

public class Child implements Serializable {
    @Id
    @GeneratedValue(strategy = GenerationType.TABLE)
    @JsonProperty(access= Access.READ_ONLY)
    private Long id;

    @OneToOne(cascade=CascadeType.REMOVE, fetch = FetchType.LAZY)
    @JoinColumn(name = "parent_id")
    @JsonIdentityInfo(generator=ObjectIdGenerators.PropertyGenerator.class, property = "id")
    @JsonIdentityReference(alwaysAsId = true)
    private Parent parent;

    //other attributes
    //setters and getters
}

public class Parent implements Serializable {
    @Id
    @GeneratedValue(strategy = GenerationType.TABLE)
    @JsonProperty(access= Access.READ_ONLY)
    private Long id;`

    //other attributes
    //setters and getters
}

我正在尝试为子实体创建RESTFul @Post方法，其中客户端（最终用户）必须提供有效的父代ID才能创建新的子代（必须先创建父代，然后客户端应提供

仅创建父母的ID，而不是创建新孩子的整个父属性。

下面是我的帖子方法

@POST
@ApiOperation(value = "Add a new child to the database")
@ApiResponses(value = {
    @ApiResponse(code = 201, message = "child created successfully."),
    @ApiResponse(code = 400, message = "Invalid child supplied in request body"),
    @ApiResponse(code = 409, message = "child supplied in request body conflicts with an existing child"),
    @ApiResponse(code = 500, message = "An unexpected error occurred whilst processing the request")
})

public Response createChild(@ApiParam(required = true)Child child) {
    if (child == null) {
        throw new RestServiceException("Bad Request", Response.Status.BAD_REQUEST);
    }

    Response.ResponseBuilder builder;

    try {
        // Go add the new child.
        childService.create(child);

       // Create a "Resource Created" 201 Response and pass the child back in case it is needed.
        builder = Response.status(Response.Status.CREATED).entity(child);
    } catch (ConstraintViolationException ce) {
        //Handle bean validation issues
        Map<String, String> responseObj = new HashMap<>();

        for (ConstraintViolation<?> violation : ce.getConstraintViolations()) {
            responseObj.put(violation.getPropertyPath().toString(), violation.getMessage());
        }
        throw new RestServiceException("Bad Request", responseObj, Response.Status.BAD_REQUEST, ce);
    } catch (Exception e) {
        // Handle generic exceptions
        throw new RestServiceException(e);
    }

    log.info("createChild completed. child = " + child.toString());
    return builder.build();
}

我对孩子的JSON表示具有类似的属性（其中 parent 指代父id）

{
    "Parent": 0,
     ...
}

当我测试我的post方法时，这里的问题是参数中的子对象始终为null !!，因为我试图获取该子对象的自动生成的ID（child.getId（）），并且它为null。

那么我该如何为两个相关实体创建一个post方法，其中客户端应仅提供现有父实体的ID？

RESTFul @Post建立独立的@OneToOne单向关系

0 个答案: