theymeleaf error handling
@Entity
public class User {
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
private Long id;
@NotEmpty(message = "User's name cannot be empty.")
@Size(min = 5, max = 250)
private String fullName;
@NotEmpty(message = "User's email cannot be empty.")
private String email;
@NotNull(message = "User's age cannot be null.")
@Min(value = 18)
private Integer age;
private String country;
private String phoneNumber;
// getters and setters
}