当我从html表单传递值时，为什么在我的post api期间出现'Column not not null'的错误

Question

When I try to test this by running my application, navigating to the admin.html page. I fill out a value for a first name, last name and email in the form. On click of the submit button, an error appears for 'Column email cannot be null'. I have excluded code such as getters,setters, contructors etc. for brevity. This is my admin.html page where I have a form which I use to post values to my api where the values are used to create an employee object

<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>

This is my POST method in EmployeeAPI.java class where I handle the post and create an object with the values passed in from the form and try to persist this new object

@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;
}

This is my Employee.java model class - I have a constructor for an employee with just firstName,lastName and email and one for all values.

@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;

This is the error I am seeing on my server side

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

During debugging of the EmployeeAPI the values were coming in null from the front end