Question

我正在玩龙目岛并且已经通过了许多链接，但它们都没有为我工作。

Person.java

@Setter @Getter
@ToString
@AllArgsConstructor
//@NoArgsConstructor
@RequiredArgsConstructor
@Entity
public class Person {
    @Id
    @GeneratedValue
    private Long id;

    @NotNull
    @Size(min = 1, max = 20)
    private String firstName;

    @NotNull
    @Size(min = 1, max = 50)
    private String lastName;
}

PersonController.java

@RestController
@RequestMapping("/people")
public class PersonController {
    @Autowired
    private PersonRepository personRepository;

    @RequestMapping(value = "", method = RequestMethod.POST)
    @ResponseStatus(HttpStatus.CREATED)
    public void createPerson(@RequestBody Person person) {
        personRepository.save(new Person(person.getFirstName(), person.getLastName()));  //line-34
    }
}

但它不允许我创建两个参数构造函数

Multiple markers at this line
    - The constructor Person(String, String) is undefined
    - The method save(S) in the type CrudRepository<Person,Long> is not applicable for the arguments 
     (Person)

在第34号线上破坏......

修改-1：

 @RequestMapping(value = "/{id}", method = RequestMethod.PUT)
    @ResponseStatus(HttpStatus.NO_CONTENT)
    public void updatePerson(@PathVariable("id") Long id, @RequestBody Person person) {
        Person existingPerson = personRepository.findOne(id);
        existingPerson.setFirstName(person.getFirstName());
        existingPerson.setLastName(person.getLastName());
        personRepository.save(existingPerson);
    }

这是错误

The method setFirstName(String) is undefined for the type Person

我所做的改变

@Setter @Getter
@ToString
@AllArgsConstructor
//@NoArgsConstructor
@RequiredArgsConstructor()
@Entity
public class Person {
    @Id
    @GeneratedValue
    private Long id;

    @NotNull
    @Size(min = 1, max = 20)
    private final String firstName;

    @NotNull
    @Size(min = 1, max = 50)
    private final String lastName;
}

- ===================

修改-2

以下是最终结果：

@Setter @Getter
@ToString
@AllArgsConstructor
@RequiredArgsConstructor
@Entity
public class Person {
    @Id
    @GeneratedValue
    private Long id;

    @NotNull
    @Size(min = 1, max = 20)
    private String firstName;

    @NotNull
    @Size(min = 1, max = 50)
    private String lastName;

    public Person(String firstName, String lastName){
        this.firstName = firstName;
        this.lastName = lastName;
    }
}

Answer 1

您在这些字段上没有Lomboks @NonNull注释。我刚才注意到了。

您在这些字段上只有@javax.validation.constraints.NotNull注释ṣ@RequiredArsgConstructor不适用于此。

除@NonNull注释外，还添加@NotNull。可能您不再需要@NotNull，所以也尝试将其删除。

@NonNull 
@NotNull
@Size(min = 1, max = 20)
private String firstName;

@NonNull 
@NotNull
@Size(min = 1, max = 50)
private String lastName;

如何让lombok为非空字段创建构造函数，因为@RequiredArgsConstructor似乎不起作用？

1 个答案: