java - 当我从 html 表单传递值时，为什么我在 post api 期间收到 'Column cannot be null' 错误

Question

当我尝试通过运行我的应用程序来测试它时，导航到 admin.html 页面。我在表单中填写了名字、姓氏和电子邮件的值。单击提交按钮时，出现“列电子邮件不能为空”的错误。为了简洁起见，我排除了诸如 getter、setter、contructor 等代码。这是我的 admin.html 页面，我在其中有一个表单，用于将值发布到我的 api，其中这些值用于创建员工对象

<form role="form" action="api/employees/create" method="post">
    <div class="form-group">
        <label for="firstName">First Name</label>
        <input type="text" class="form-control" id="firstName" placeholder="Enter first name">
    </div>
    <div class="form-group">
        <label for="lastName">Last Name</label>
        <input type="text" class="form-control" id="lastName" placeholder="Enter last name">
    </div>
    <div class="form-group">
        <label for="email">Email</label>
        <input type="text" class="form-control" id="email" placeholder="Enter email">
    </div>
    <button type="submit" class="btn btn-success btn-block">Create</button>
</form>

这是我在 EmployeeAPI.java 类中的 POST 方法，我在其中处理帖子并使用从表单传入的值创建一个对象并尝试保留这个新对象

@POST
@Path("create")
@Consumes(MediaType.APPLICATION_FORM_URLENCODED)
@Produces(MediaType.TEXT_HTML)
public Response createEmployee(@FormParam(value = "firstName") String firstName,
                               @FormParam(value = "lastName") String lastName,
                               @FormParam(value = "email") String email) {
    SessionFactory factory = HibernateUtil.getSessionFactory();
    Session session = factory.getCurrentSession();
    URI location;
    try{
        session.getTransaction().begin();

        Employee newEmployee = new Employee();
        newEmployee.setFirstName(firstName);
        newEmployee.setLastName(lastName);
        newEmployee.setEmail(email);

        session.persist(newEmployee);
        session.getTransaction().commit();
        session.close();

        location = new URI("http://localhost:8080/index.html");
        return Response.temporaryRedirect(location).build();
    } catch (Exception e) {
        session.getTransaction().rollback();
        e.printStackTrace();
    }
    return null;
}

这是我的 Employee.java 模型类 - 我有一个只包含 firstName、lastName 和 email 的员工构造函数，以及一个用于所有值的构造函数。

@XmlRootElement
@Entity
public class Employee {

@Id
@GeneratedValue
private int id;

@Expose
@Column(nullable = false)
private String firstName;

@Expose
@Column(nullable = false)
private String lastName;

@Expose
@Column(nullable = false, unique = true)
private String email;

这是我在服务器端看到的错误

Hibernate: insert into Employee (availability_id, email, firstName, isAdmin, isManager, isMentee, isMentor, lastName, mentorDuration, topic_name, id) values (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
2019-03-04 16:07:41 WARN  SqlExceptionHelper:129 - SQL Error: 1048, SQLState: 23000
2019-03-04 16:07:41 ERROR SqlExceptionHelper:131 - Column 'email' cannot be null
2019-03-04 16:07:41 INFO  AbstractBatchImpl:193 - HHH000010: On release of batch it still contained JDBC statements
2019-03-04 16:07:41 ERROR ExceptionMapperStandardImpl:39 - HHH000346: Error during managed flush [org.hibernate.exception.ConstraintViolationException: could not execute statement]

Answer 1

在调试 EmployeeAPI 期间，前端的值变为 null