JAVA Annotation - GWT impl of email validation on bean field

import javax.validation.Constraint;
import javax.validation.Payload;
import javax.validation.ReportAsSingleViolation;
import javax.validation.constraints.Pattern;
import java.lang.annotation.Documented;
import java.lang.annotation.Retention;
import java.lang.annotation.Target;

import static java.lang.annotation.ElementType.*;
import static java.lang.annotation.RetentionPolicy.RUNTIME;

/**
 * Replacement for the Hibernate Email constraint that is not supported by GWT.
 * <p/>
 */
@Documented
@Constraint(validatedBy = {})
@Pattern(regexp = "^[a-z0-9!#$%&'*+/=?^_`{|}~-]+(\\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*@([a-z0-9!#$%&'*+/=?^_`{|}~-]+(\\" +
        ".[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*|\\[[0-9]{1,3}\\.[0-9]{1,3}\\.[0-9]{1,3}\\.[0-9]{1,3}\\])$", flags = Pattern
        .Flag.CASE_INSENSITIVE)
@ReportAsSingleViolation
@Target({METHOD, FIELD, ANNOTATION_TYPE, CONSTRUCTOR, PARAMETER})
@Retention(RUNTIME)
public @interface Email {
    String message() default "{org.hibernate.validator.constraints.Email.message}";

    Class<?>[] groups() default {};

    Class<? extends Payload>[] payload() default {};

    /**
     * Defines several {@code @Email} annotations on the same element.
     */
    @Target({METHOD, FIELD, ANNOTATION_TYPE, CONSTRUCTOR, PARAMETER})
    @Retention(RUNTIME)
    @Documented
    public @interface List {
        Email[] value();
    }
}