spring hibernate 没有得到参数的值

spring hibernate did not get the value of parameter

我尝试通过邮递员使用 post 方法对我的 spring 启动应用程序进行 API 调用。 这是输入:

{
  "username": "name",
  "password": "1234",
  "age": 12,
  "salary": 5000,
  "role": 1
}

控制器中的代码如下:

@RequestMapping(value = "/signup", method = RequestMethod.POST, consumes = MediaType.APPLICATION_JSON_VALUE)
    public ResponseEntity<?> saveUser(@RequestBody UserDto user) {
        try {
            System.out.println(user.getUsername()); // => name
            System.out.println(user.getPassword()); // => 1234
            System.out.println(user.getSalary()); // => 5000
            System.out.println(user.getRole()); // => 1
            System.out.println(user.getAge()); // => 12
            userService.save(user);
            return ResponseEntity.ok().body("insert done");
        } catch (Exception e) {
            return ResponseEntity.badRequest().body(e.getMessage());
        }
    }

这是我的 User.java

@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
@Column
private String username;
@Column
@JsonIgnore
private String password;
@Column
private long salary;
@Column
private int age;
@ManyToOne(fetch = FetchType.LAZY, optional = false)
@JoinColumn(name = "role_id")
private Role role;
// getters and setters

这是我的 Role.java

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

@Column(name = "role_name", nullable = false)
private String roleName;
// getters and setters

这是我的UserDto.java

private String username;
private String password;
private int age;
private long salary;
private int role;
// getters and setters

这是我的RoleDto.java

private Long id;
private String roleName;
// getters and setters

问题:抛出错误'Column 'role_id' cannot be null'

这里是在userServiceImpl中: 下面一行 (BeanUtils) 是指 here.

    @Override
    public User save(UserDto user) throws Exception {
        User newUser = new User();
        BeanUtils.copyProperties(user, newUser, "password");
        newUser.setPassword(bcryptEncoder.encode(user.getPassword()));
        try {
            userDao.save(newUser);
        } catch (Exception e) {
            throw new Exception(e);
            // this throw "Column role_id cannot be null"
        }
        return newUser;
    }

但是,如果我使用下面的代码,setRole 方法是 not applicable 因为我在 DTO 中将 user.getRole() 定义为 int 但定义 newUser.setRole()User 实体中作为 Role。但是,如果我将 User 实体中的 setRole 更改为 int,那么我如何告诉 spring 关于 User 之间的 ManyToOne 关系和 Role?

@Override
public User save(UserDto user) throws Exception {
    User newUser = new User();
    newUser.setUsername(user.getUsername());
    newUser.setPassword(bcryptEncoder.encode(user.getPassword()));
    newUser.setAge(user.getAge());
    newUser.setSalary(user.getSalary());
    newUser.setRole(user.getRole()); // here is the problem
    try {
        userDao.save(newUser);
    } catch (Exception e) {
        throw new Exception(e);
    }
    return newUser;
}

注意:我想我只是想将 role 的输入参数设为上面提供的 integer

由于您在请求中收到了 1 个角色,因此您应该执行以下操作:

Role role = new Role();
role.setId(user.getRole());
role.setRoleName("some name");
newUser.setRole(role);

在代码的第一部分,问题可能出在 BeanUtils.copyProperties(user, newUser, "password");,如果您尝试在该行之后调试或打印 newUser,您将看到 BeanUtils 无法正确填充所有内容newUser 对象的字段。这是因为在目标 (newUser) 中,字段 role 的类型是 Role,而在源(用户)中,该字段的类型只是 int.