8. Extract E-mails

/* Write a program to extract all email addresses from given text.
 * The text comes at the first input line.
 * Print the emails in the output, each at a separate line.
 * Emails are considered to be in format <user>@<host>, where:
 * <user> is a sequence of letters and digits, where '.', '-' and '_' can appear between them.
 * Examples of valid users: "stephan", "mike03", "s.johnson", "st_steward", "softuni-bulgaria",
 * "12345". Examples of invalid users: ''--123", ".....", "nakov_-", "_steve", ".info".
 * <host> is a sequence of at least two words, separated by dots '.'.
 * Each word is sequence of letters and can have hyphens '-' between the letters.
 * Examples of hosts: "softuni.bg", "software-university.com", "intoprogramming.info",
 * "mail.softuni.org". Examples of invalid hosts: "helloworld", ".unknown.soft.",
 * "invalid-host-", "invalid-".
 * Example of valid emails: info@softuni-bulgaria.org, kiki@hotmail.co.uk,
 * no-reply@github.com, s.peterson@mail.uu.net, info-bg@software-university.software.academy. */

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

public class _08_ExtractEmails {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Scanner scan = new Scanner(System.in);
        System.out.println("Enter your text on single line:");
        String inputText = scan.nextLine();

        Pattern mailPattern = Pattern
                .compile("[A-Za-z]+[.-_]*[A-Za-z]+@[A-Za-z]+[-]*[.A-Za-z]+[A-Za-z]");

        Matcher matcher = mailPattern.matcher(inputText);
        System.out
                .println("All extracted E-mail addresses from Given Text are:");
        while (matcher.find()) {
            System.out.println(matcher.group());
        }
    }

}