One more important thing to note is that email addresses are case insensitive. So we will use case insensitive flag to create the pattern object.
[email protected] – “.a” is not a valid tld, last tld must contains at least two characters 4. mkyong()*@– email’s is only allow character, digit, underscore and dash 8.In the last post, I explained about java regular expression in detail with some examples. In this real life example, I am trying to validate email addresses using java regular expression. Keep in mind, though, you'll still have to send a verification email to the address if you want to ensure it's a real email, and that the owner wants it used on your site. Because it has attracted low-quality or spam answers that had to be removed, posting an answer now requires 10 reputation on this site (the association bonus does not count).If you are trying to do a form validation received from the client, or just a bean validation - keep it simple. Would you like to answer one of these unanswered questions instead?Just for fun, I will copy and paste the whole thing.Apache Commons is generally known as a solid project. J" = 17 Top-Level-Domain muss 2 Stellen haben null = 1 Eingabestring nicht gesetzt " " = 2 durch TRIM eine Laenge von 0 " A . D " = 12 Leerzeichen innerhalb der e Mail-Adresse "(? ]@.: " = 12 Sonderzeichen sind nicht erlaubt Thank you for your interest in this question.Les Hazlewood has written a very thorough RFC 2822 compliant email validator class using Java regular expressions. Simple regex won't understand it, even though the email should be valid. Anything more complex becomes error-prone or even contain hidden performance killers. The only comprehensive RFC compliant regex based validator I'm aware of is email-rfc2822-validator with its 'refined' regex appropriately named It also provides a lot of methods to access certain parts of the address (left-hand side, right-hand side, personal names, comments, etc), to parse/validate mailbox-list headers, to parse/validate the return-path (which is unique among the headers), and so forth. The email address can only be checked for its format conformance. I'd also stay away from so called simple 'non-restrictive' regex; there's no such thing. The code as written has a javamail dependency, but it's easy to remove if you don't want the minor functionality it provides. However, its thoroughness (or the Java RE implementation) leads to inefficiency - read the comments about parsing times for long addresses. For example @ is allowed multiple times depending on context, how do you know the required one is there?