我正在学习Spring-Boot的特性，也在Postman上学习过。但是当我运行代码时，我在Postman上得到了400个错误请求，如下所示：“缺少必需的请求正文：是我遗漏了一个属性还是编码一路出错了？

@RestController
 @RequestMapping("/api/board")
 @CrossOrigin
public class ProjectTaskController {

@Autowired
private ProjectTaskService projectTaskService;

@PostMapping("")
public ResponseEntity<?> addPTToBoard( @Valid @RequestBody ProjectTask projectTask, BindingResult result){
    if(result.hasErrors()) {
        Map<String, String> errorMap= new HashMap<>();

        for(FieldError error: result.getFieldErrors()) {
            errorMap.put(error.getField(), error.getDefaultMessage());
        }
         return new ResponseEntity<Map<String, String>>(errorMap, HttpStatus.BAD_REQUEST);
    }

    ProjectTask newPT= projectTaskService.saveOrUpdateProjectTask(projectTask);
    return new ResponseEntity<ProjectTask>(newPT, HttpStatus.CREATED);
}

projectTask代码，它也有getter和setter。

@Entity
public class ProjectTask {

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

@NotBlank(message = "summary cannot be blank")
private String summary;
private String acceptanceCriteria;
private String status;

public ProjectTask() {

}

此处为Postman request