Validation form in Spring using @Valid not work

Question

I want to validation my form, but this not work. My entity class

import java.io.Serializable;
import java.util.Set;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.OneToMany;
import javax.persistence.Table;
import javax.validation.constraints.NotNull;
import javax.validation.constraints.Size;

import org.hibernate.validator.constraints.Email;

@Entity
@Table(name = "users")
public class User implements Serializable {

    private static final long serialVersionUID = 1L;
    @Id
    @GeneratedValue
    @Column(name = "id")
    private Integer id;
    @NotNull
    @Size(max = 20)
    @Column(name = "username")
    private String username;
    @NotNull
    @Size(max = 20)
    @Column(name = "password")
    private String password;
    @NotNull
    @Size(max = 20)
    @Column(name = "firstName")
    private String firstName;
    @NotNull
    @Size(max = 20)
    @Column(name = "lastName")
    private String lastName;
    @Size(min = 11, max = 11)
    @Column(name = "personalId")
    private String personalId;
    @Size(max = 40)
    @Column(name = "city")
    private String city;
    @Size(max = 40)
    @Column(name = "address")
    private String address;
    @NotNull
    @Email
    @Size(max = 30)
    @Column(name = "email")
    private String email;
    @Size(min = 9, max = 9)
    @Column(name = "phone")
    private String phone;
    @OneToMany(mappedBy = "user")
    private Set<UserRole> userRoleSet;
}

adminList.jsp and form go to addAdmin page:

<form action="addAdminForm" method="post">
    <input type="submit" value="Dodaj administratora" />
</form>

addAdmin.jsp page formule:

    <form:form action="addAdmin" modelAttribute="user" method="post">
    <form:label path="username">Login: </form:label>
    <form:input path="username" />
    <form:errors path="username" cssClass="error" />
    <br />
    <form:label path="password">Hasło: </form:label>
    <form:password path="password" />
    <form:errors path="password" cssClass="error" />
    <br />
    <form:label path="firstName">Imię: </form:label>
    <form:input path="firstName" />
    <form:errors path="firstName" cssClass="error" />
    <br />
    <form:label path="lastName">Nazwisko: </form:label>
    <form:input path="lastName" />
    <form:errors path="lastName" cssClass="error" />
    <br />
    <form:label path="email">Email: </form:label>
    <form:input path="email" />
    <form:errors path="email" cssClass="error" />
    <br />
    <input type="submit" value="Dodaj" />
</form:form>

Controller:

    @RequestMapping(value = "/admin/addAdminForm", method = RequestMethod.POST)
public ModelAndView goAddAdminForm() {
    ModelAndView mav = new ModelAndView("admin/addadmin");
    mav.addObject("user", new User());
    return mav;
}

@RequestMapping(value = "/admin/addAdmin", method = RequestMethod.POST)
public String addAdmin(@Valid @ModelAttribute("user") User user,
        BindingResult result, Model model) {
    if (result.hasErrors()) {
        return "admin/addadmin";
    } else {
        userService.createUser(user);
        user = userService.findByUsername(user.getUsername());
        UserRole userRole = new UserRole("ROLE_ADMIN");
        userRole.setUser(user);
        userRoleService.createUserRole(userRole);
        return "redirect:/admin/adminlist";
    }
}

When i try send empty formule i should get error messages result.hasErrors() not return error and my application go to else and try save user. Why @Valid not work?

Answer 1

Are you sure that the validations don't work? Unless you have for example StringTrimmerEditor registered, your fields will actually be String instances with length equal to 0, not null values when you submit the form and therefore the annotation would consider such values to be valid.

If you want to validate that String is not blank (not null and not an empty String), use for instance the @NotBlank annotation. Also I just tried it myself and the @Email annotation also passes for empty Strings, which would mean that your empty form IS actually valid right now.