The Contact entity uses the @NotNull, @Pattern, and @Past constraints on the persistent attributes.
The @NotNull constraint marks the attribute as a required field. The attribute must be set to a non-null value before the entity can be persisted or modified. Bean Validation will throw a validation error if the attribute is null when the entity is persisted or modified.
The @Pattern constraint defines a regular expression that the value of the attribute must match before the entity can be persisted or modified. This constraint has two different uses in address-book.
The regular expression declared in the @Pattern annotation on the email field matches email addresses of the form name@domain name.top level domain, allowing only valid characters for email addresses. For example, username@example.com will pass validation, as will firstname.lastname@mail.example.com. However, firstname,lastname@example.com, which contains an illegal comma character in the local name, will fail validation.
The mobilePhone and homePhone fields are annotated with a @Pattern constraint that defines a regular expression to match phone numbers of the form (xxx) xxx–xxxx.
The @Past constraint is applied to the birthday field, which must be a java.util.Date in the past.
Here are the relevant parts of the Contact entity class:
@Entity public class Contact implements Serializable { private static final long serialVersionUID = 1L; @Id @GeneratedValue(strategy = GenerationType.AUTO) private Long id; @NotNull protected String firstName; @NotNull protected String lastName; @Pattern(regexp="[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\\." +"[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*" +"@(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?", message="{invalid.email}") protected String email; @Pattern(regexp="^\\(?(\\d{3})\\)?[- ]?(\\d{3})[- ]?(\\d{4})$", message="{invalid.phonenumber}") protected String mobilePhone; @Pattern(regexp="^\\(?(\\d{3})\\)?[- ]?(\\d{3})[- ]?(\\d{4})$", message="{invalid.phonenumber}") protected String homePhone; @Temporal(javax.persistence.TemporalType.DATE) @Past protected Date birthday; ... }