Java Email Validate isValidEmailAddress(String addr)

Description

is Valid Email Address

License

Apache License

Declaration

public static boolean isValidEmailAddress(String addr) 

Method Source Code

//package com.java2s;
/*//from  ww  w .  ja  va  2s .c  o  m
 * Copyright 2012 Donghyuck, Son
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class Main {
    private static Pattern basicAddressPattern;
    private static Pattern validUserPattern;
    private static Pattern domainPattern;
    private static Pattern ipDomainPattern;
    private static Pattern tldPattern;

    public static boolean isValidEmailAddress(String addr) {
        if (addr == null)
            return false;
        addr = addr.trim();
        if (addr.length() == 0)
            return false;
        Matcher matcher = basicAddressPattern.matcher(addr);
        if (!matcher.matches())
            return false;
        String userPart = matcher.group(1);
        String domainPart = matcher.group(2);
        matcher = validUserPattern.matcher(userPart);
        if (!matcher.matches())
            return false;
        matcher = ipDomainPattern.matcher(domainPart);
        if (matcher.matches()) {
            for (int i = 1; i < 5; i++) {
                String num = matcher.group(i);
                if (num == null)
                    return false;
                if (Integer.parseInt(num) > 254)
                    return false;
            }

            return true;
        }
        matcher = domainPattern.matcher(domainPart);
        if (matcher.matches()) {
            String tld = matcher.group(matcher.groupCount());
            matcher = tldPattern.matcher(tld);
            return tld.length() == 3 || matcher.matches();
        } else {
            return "localhost".equals(domainPart);
        }
    }
}

Related

1. isValidEmail(String email)
2. isValidEmail(String emailAddress)
3. isValidEmail(String eMailAddress)
4. IsValidEmail(String input)
5. isValidEmailAddr(String str)
6. isValidEmailAddress(String aEmailAddress)
7. isValidEmailAddress(String email)
8. isValidEmailAddress(String email)
9. isValidEmailAddress(String email)