email address format validator

EmailAddressFormatValidator.kt

import java.util.function.Predicate
import java.util.regex.Pattern
import org.springframework.stereotype.Component

/**
 * Email address format validator.
 *
 * @author Jeffrey Sadeli
 * @since 2023-05-16
 */
@Component
class EmailAddressFormatValidator : Predicate<String> {

  /**
   * Validates email address format.
   *
   * @param emailAddress the input argument
   * @return `true` if is a valid email address format, otherwise `false`.
   * @author Jeffrey Sadeli
   * @see <a href="https://datatracker.ietf.org/doc/html/rfc5322#section-3.4">RFC 5322</a>
   * @see <a href="https://owasp.org/www-community/OWASP_Validation_Regex_Repository">OWASP</a>
   * @since 2023-05-16
   */
  override fun test(emailAddress: String): Boolean {
    // slight modification to OWASP regex: placing a 64-characters limit in the local part
    val regex: String =
      """^(?=.{1,64}@)[a-zA-Z\d_+&*-]+(?:\.[a-zA-Z\d_+&*-]+)*""" +
        "@" +
        """(?:[a-zA-Z\d-]+\.)+[a-zA-Z]{2,7}${'$'}"""
    return Pattern.compile(regex).matcher(emailAddress).matches()
  }
}