Subversion Repositories javautils

/*

 * @(#)EmailSyntaxValidator.java

 *

 * Summary: Validate syntax of email addresses.

 *

 * Copyright: (c) 2002-2010 Roedy Green, Canadian Mind Products, http://mindprod.com

 *

 * Licence: This software may be copied and used freely for any purpose but military.

 *          http://mindprod.com/contact/nonmil.html

 *

 * Requires: JDK 1.5+

 *

 * Created with: IntelliJ IDEA IDE.

 *

 * Version History:

 *  1.7 2007-08-21

 */

package com.mindprod.bulk;

// Download newest version here:

// http://mindprod.com/products1.html#BULK

// SVN:

// http://wush.net/svn/mindprod/com/mindprod/bulk/EmailSyntaxValidator.java

// TODO: BAD TLDS + PSEUDO (TOR: EXIT ETC)

// TODO: Awaiting official commit for this Patch

// CHANGELOG BY DANIEL MARSCHALL

//

//Added ccTLDs

//

//.ax = Aland Islands

//.eu = European Union

//.me = Montenegro

//.rs = Serbia

//.su = Soviet Union (being phased out)

//.tl = Timor-Leste

//

//Deleted ccTLDs

//

//.bv = Bouvet Island [Allocated/unused]

//.eh = Western Sahara [Reserved/unassigned]

//.fx = UNKNOWN

//.gb = United Kingdom [Allocated/unused]

//.pm = Saint Pierre and Miquelon [Allocated/unused]

//.sj = Svalbard and Jan Mayen [Allocated/unused]

//.so = Somalia [Allocated/unused]

//.um = United States Minor Outlying Islands [Reserved/unassigned]

//.yt = Mayotte [Allocated/unused]

//.yu = Yugoslavia [Deleted/retired]

//

//Added BAD TLDs

//

//.example (RFC 2606)

//.localhost (RFC 2606)

//.test (RFC 2606)

//

//Added official TLDs

//

//.arpa (infrastructure TLD)

//.tel (sponsored TLD)               -- official TLD or rare TLD?

//.mobi (sponsored TLD)              -- official TLD or rare TLD?

//.jobs (sponsored TLD)              -- official TLD or rare TLD?

//.cat (sponsored TLD)               -- official TLD or rare TLD?

//

//Other changes

//

//* Commented out unused debugging stuff

//* Removed main procedure and syso import

import javax.mail.internet.AddressException;

import javax.mail.internet.InternetAddress;

import java.util.Arrays;

import java.util.HashSet;

import java.util.Locale;

import java.util.regex.Matcher;

import java.util.regex.Pattern;

/**

 * Validate syntax of email addresses.

 * <p/>

 * Does not probe to see if mailserver exists in DNS or online. See MailProber

 * for that. See ValidateEmailFile for an example of how to use this class.

 *

 * @author Roedy Green, Canadian Mind Products

 * @version 1.7 2007-08-21

 * @since 2002

 */

// TODO: @version check validity of & in first part of email address. Appears in

// practice.

public final class EmailSyntaxValidator {

        // ------------------------------ CONSTANTS ------------------------------

        /**

         * True if want extra debugging output.

         */

        // @SuppressWarnings( { "UnusedDeclaration" })

        // private static final boolean DEBUGGING = false;

        /**

         * Country where this program is running.

         */

        private static final String THIS_COUNTRY = Locale.getDefault().getCountry()

                        .toLowerCase();

        /**

         * Bad top level domains -- ones never valid.

         */

        private static final HashSet<String> BAD_TLDS = hmaker(new String[] {

                        "invalid", "nowhere", "noone", "test", "example", "localhost", });

        /**

         * Top level domains for countries.

         */

        private static final HashSet<String> NATIONAL_TLDS = hmaker(new String[] {

                        "ac", "ad", "ae", "af", "ag", "ai", "al", "am", "an", "ao", "aq",

                        "ar", "as", "at", "au", "aw", "ax", "az", "ba", "bb", "bd", "be",

                        "bf", "bg", "bh", "bi", "bj", "bm", "bn", "bo", "br", "bs", "bt",

                        "bw", "by", "bz", "ca", "cc", "cd", "cf", "cg", "ch", "ci", "ck",

                        "cl", "cm", "cn", "co", "cr", "cu", "cv", "cx", "cy", "cz", "de",

                        "dj", "dk", "dm", "do", "dz", "ec", "ee", "eg", "er", "es", "et",

                        "eu", "eu", "fi", "fj", "fk", "fm", "fo", "fr", "ga", "gd", "ge",

                        "gf", "gg", "gh", "gi", "gl", "gm", "gn", "gp", "gq", "gr", "gs",

                        "gt", "gu", "gw", "gy", "hk", "hm", "hn", "hr", "ht", "hu", "id",

                        "ie", "il", "im", "in", "io", "iq", "ir", "is", "it", "je", "jm",

                        "jo", "jp", "ke", "kg", "kh", "ki", "km", "kn", "kp", "kr", "kw",

                        "ky", "kz", "la", "lb", "lc", "li", "lk", "lr", "ls", "lt", "lu",

                        "lv", "ly", "ma", "mc", "md", "me", "mg", "mh", "mk", "ml", "mm",

                        "mn", "mo", "mp", "mq", "mr", "ms", "mt", "mu", "mv", "mw", "mx",

                        "my", "mz", "na", "nc", "ne", "nf", "ng", "ni", "nl", "no", "np",

                        "nr", "nu", "nz", "om", "pa", "pe", "pf", "pg", "ph", "pk", "pl",

                        "pn", "pr", "ps", "pt", "pw", "py", "qa", "re", "ro", "rs", "ru",

                        "rw", "sa", "sb", "sc", "sd", "se", "sg", "sh", "si", "sk", "sl",

                        "sm", "sn", "sr", "st", "su", "sv", "sy", "sz", "tc", "td", "tf",

                        "tg", "th", "tj", "tk", "tl", "tm", "tn", "to", "tp", "tr", "tt",

                        "tv", "tw", "tz", "ua", "ug", "uk", "us", "uy", "uz", "va", "vc",

                        "ve", "vg", "vi", "vn", "vu", "wf", "ws", "ye", "za", "zm", "zw", });

        /**

         * Official top level domains.

         */

        private static final HashSet<String> OFFICIAL_TLDS = hmaker(new String[] {

                        "aero", "biz", "coop", "com", "edu", "gov", "info", "mil",

                        "museum", "name", "net", "org", "pro", "tel", "mobi", "jobs",

                        "cat", "arpa", });

        /**

         * Rarely used top level domains

         */

        private static final HashSet<String> RARE_TLDS = hmaker(new String[] {

                        "cam", "mp3", "agent", "art", "arts", "asia", "auction", "aus",

                        "bank", "cam", "chat", "church", "club", "corp", "dds", "design",

                        "dns2go", "e", "email", "exp", "fam", "family", "faq", "fed",

                        "film", "firm", "free", "fun", "g", "game", "games", "gay", "ger",

                        "globe", "gmbh", "golf", "gov", "help", "hola", "i", "inc", "int",

                        "jpn", "k12", "kids", "law", "learn", "llb", "llc", "llp", "lnx",

                        "love", "ltd", "mag", "mail", "med", "media", "mp3", "netz", "nic",

                        "nom", "npo", "per", "pol", "prices", "radio", "rsc", "school",

                        "scifi", "sea", "service", "sex", "shop", "sky", "soc", "space",

                        "sport", "tech", "tour", "travel", "usvi", "video", "web", "wine",

                        "wir", "wired", "zine", "zoo", });

        /**

         * regex to allow dots anywhere, but not at start of domain name, no +

         */

        private static final Pattern p3 = Pattern

                        .compile("[a-z0-9\\-_\\.]++@[a-z0-9\\-_]++(\\.[a-z0-9\\-_]++)++");

        /**

         * regex IP style names, no +

         */

        private static final Pattern p4 = Pattern

                        .compile("[a-z0-9\\-_]++(\\.[a-z0-9\\-_]++)*@\\[([0-9]{1,3}\\.){3}[0-9]{1,3}\\]");

        /**

         * regex to allow - _ dots in name, no +

         */

        private static final Pattern p5 = Pattern

                        .compile("[a-z0-9\\-_]++(\\.[a-z0-9\\-_]++)*@[a-z0-9\\-_]++(\\.[a-z0-9\\-_]++)++");

        /**

         * regex to allow _ - in name, lead and trailing ones are filtered later, no

         * +.

         */

        private static final Pattern p9 = Pattern

                        .compile("[a-z0-9\\-_]++@[a-z0-9\\-_]++(\\.[a-z0-9\\-_]++)++");

        /**

         * regex to split into fields

         */

        private static final Pattern splitter = Pattern.compile("[@\\.]");

        // -------------------------- PUBLIC STATIC METHODS

        // --------------------------

        /**

         * Check how likely an email address is to be valid. The higher the number

         * returned, the more likely the address is valid. This method does not

         * probe the internet in any way to see if the corresponding mail server or

         * domain exists.

         *

         * @param email

         *            bare computer email address. e.g. roedyg@mindprod.com No

         *            "Roedy Green" <roedyg@mindprod.com> style addresses. No local

         *            addresses, e.g. roedy.

         *

         * @return <ul>

         *         <li>0 = email address is definitely malformed, e.g. missing

         * @. ends in .invalid</li> <li>1 = address does not meet one of the valid

         *    patterns below. It still might be ok according to some obscure rule in

         *    RFC 822 Java InternetAddress accepts it as valid.</li> <li>2 = unknown

         *    top level domain.</li> <li>3 = dots at beginning or end, doubled in

         *    name.</li> <li>4 = address of form xxx@[209.139.205.2] using IP</li>

         *    <li>5 = address of form xxx.xxx.xxx@xxx.xxx.xxx Dots _ or - in first

         *    part of name</li> <li>6 = addreess of form xxx@xxx.xxx.xxx rare, but

         *    known, domain</li> <li>7 = address of form xxx@xxx.xxx.ca or any

         *    national suffix.</li> <li>8 = address of form xxx@xxx.xxx.xx the

         *    matching this national suffix, e.g. .ca in Canada, .de in Germany</li>

         *    <li>9 = address of form xxx@xxx.xxx.com .org .net .edu .gov .biz --

         *    official domains</li>

         *    </ul>

         */

        public static int howValid(String email) {

                if (email == null) {

                        return 0;

                }

                email = email.trim().toLowerCase();

                int dotPlace = email.lastIndexOf('.');

                if (0 < dotPlace && dotPlace < email.length() - 1) {

                        String tld = email.substring(dotPlace + 1);

                        if (BAD_TLDS.contains(tld)) {

                                /* deliberate invalid address */

                                return 0;

                        }

                        // make sure none of fragments start or end in _ or -

                        String[] fragments = splitter.split(email);

                        boolean clean = true;

                        for (String fragment : fragments) {

                                if (fragment.startsWith("_") || fragment.endsWith("_")

                                                || fragment.startsWith("-") || fragment.endsWith("-")) {

                                        clean = false;

                                        break;

                                }

                        }// end for

                        if (clean) {

                                Matcher m9 = p9.matcher(email);

                                if (m9.matches()) {

                                        if (OFFICIAL_TLDS.contains(tld)) {

                                                return 9;

                                        } else if (THIS_COUNTRY.equals(tld)) {

                                                return 8;

                                        } else if (NATIONAL_TLDS.contains(tld)) {

                                                return 7;

                                        } else if (RARE_TLDS.contains(tld)) {

                                                return 6;

                                        } else {

                                                // TODO: Why is that 3 and not 2?

                                                return 3;/* unknown tld */

                                        }

                                }

                                // allow dots in name

                                Matcher m5 = p5.matcher(email);

                                if (m5.matches()) {

                                        if (OFFICIAL_TLDS.contains(tld)) {

                                                return 5;

                                        } else if (THIS_COUNTRY.equals(tld)) {

                                                return 5;

                                        } else if (NATIONAL_TLDS.contains(tld)) {

                                                return 5;

                                        } else if (RARE_TLDS.contains(tld)) {

                                                return 5;

                                        } else {

                                                return 2;/* unknown tld */

                                        }

                                }

                                // IP

                                Matcher m4 = p4.matcher(email);

                                if (m4.matches()) {

                                        return 4;/* can't tell TLD */

                                }

                                // allow even lead/trail dots in name, except at start of domain

                                Matcher m3 = p3.matcher(email);

                                if (m3.matches()) {

                                        if (OFFICIAL_TLDS.contains(tld)) {

                                                return 3;

                                        } else if (THIS_COUNTRY.equals(tld)) {

                                                return 3;

                                        } else if (NATIONAL_TLDS.contains(tld)) {

                                                return 3;

                                        } else if (RARE_TLDS.contains(tld)) {

                                                return 3;

                                        } else {

                                                return 2;/* unknown domain */

                                        }

                                }

                        }// end if clean

                }

                // allow even unclean addresses, and addresses without a TLD to have a

                // whack at passing RFC:822

                try {

                        /*

                         * see if InternetAddress likes it, it follows RFC:822. It will

                         * names without domains though.

                         */

                        InternetAddress.parse(email, true/* strict */);

                        // it liked it, no exception happened. Seems very sloppy.

                        return 1;

                } catch (AddressException e) {

                        // it did not like it

                        return 0;

                }

        }

        // -------------------------- STATIC METHODS --------------------------

        /**

         * build a HashSet from a array of String literals.

         *

         * @param list

         *            array of strings

         *

         * @return HashSet you can use to test if a string is in the set.

         */

        private static HashSet<String> hmaker(String[] list) {

                HashSet<String> map = new HashSet<String>(Math.max(

                                (int) (list.length / .75f) + 1, 16));

                map.addAll(Arrays.asList(list));

                return map;

        }

        // --------------------------- main() method ---------------------------

        /**

         * main debugging harness.

         *

         * @param args

         *            not used

         */

        // public static void main(String[] args) {

        // out.println(howValid("kellizer@.hotmail.com"));

        // }

}