email-rfc2822-validator

The world's only more-or-less-2822-compliant Java-based email address extractor / verifier

• Author: http://stackoverflow.com/a/13133880/441662
  • Based on: Les Hazlewood's java regex version, code: https://github.com/lhazlewood/jeav
• Origin: http://lacinato.com/cm/software/emailrelated/emailaddress
• Used in: https://github.com/bbottema/simple-java-mail

email-rfc2822-validator is available in Maven Central:

<dependency>
    <groupId>com.github.bbottema</groupId>
    <artifactId>emailaddress-rfc2822</artifactId>
    <version>2.3.1</version>
</dependency>

And just to show you that this stuff is hard, here's JavaMail's official parser's javadoc on the subject (line 669):

    /*
     * RFC822 Address parser.
     *
     * XXX - This is complex enough that it ought to be a real parser,
     *       not this ad-hoc mess, and because of that, this is not perfect.
     *
     * XXX - Deal with encoded Headers too.
     */
    @SuppressWarnings("fallthrough")
    private static InternetAddress[] parse(String s, boolean strict,
                    boolean parseHdr) throws AddressException {

Usage

There are two classes available, EmailaddressValidator and EmailAddressParser. The second is used to extract data from (complex / mangled) email strings.

For both of these, you use the EmailAddressCriteria enumeration to control RFC strictness.

Here's an example for validating an email address:

boolean isValid = EmailAddressValidator.isValid(emailaddress);
boolean isValid = EmailAddressValidator.isValid(emailaddress, EmailAddressCriteria.RECOMMENDED);
boolean isValid = EmailAddressValidator.isValid(emailaddress, EmailAddressCriteria.RFC_COMPLIANT);
boolean isValid = EmailAddressValidator.isValid(emailaddress, EnumSet.of(ALLOW_DOT_IN_A_TEXT, ALLOW_SQUARE_BRACKETS_IN_A_TEXT));

Latest Progress

v2.3.1

• #24: Bug: Published JARs for versions 2.2.0 and 2.3.0 have an invalid module name in MANIFEST.MF

v2.3.0

• #21: Make Jakarta Mail dependency used for parsing (not validation) optional

NOTE: Jakarta Mail is now an optional dependency, which you need to add yourself, but only if you use the parsing facilities of this library (rather than only the validation function)

v2.2.0

• #19: Parens not parsed properly and API documentation / usage needs improvement

v2.1.4

• #17: IllegalArgumentException when passing null to EmailAddressValidator.isValid(String)

v2.1.3

• #14: Update project to Java 1.7 and Jakarta Mail

v1.1.3

• #13: Fixed TLD limitation for domains longer than six

v1.1.2

• Fixed regression bug where name and address were switched around

v1.1.1

• This library can now be used with any javax.mail dependency from 1.5.5 and upwards.

v1.1.0

• #7: Clarified validation modes (default vs strictly rfc compliant)

NOTE: EmailAddressValidator.isValid() now validates using EmailAddressCriteria.DEFAULT rather than EmailAddressCriteria.RFC_COMPLIANT. Use EmailAddressValidator.isValidStrict() for RFC compliant validation.

v1.0.1

Initial release