regex to check email ids

Question

I am new to regex. I am checking email ids using regex.

Following is my code to match <[email protected]> with [email protected]

Pattern p = Pattern.compile("\\<(.*?)\\>");
Matcher m = p.matcher("<[email protected]>");

And its working fine. Now I want to match either <[email protected]> or [[email protected]] with [email protected].

Any suggestion will be appreciated.

Steve Chambers · Accepted Answer · 2013-09-12T12:44:56.227

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Pattern p = Pattern.compile("(<(.*?)>|\\[(.*?)])");

edited Sep 12 '13 at 12:44

answered Sep 12 '13 at 12:36

Steve Chambers

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Thanks fo the answer I am getting his syntax Error when I try this code 'Invalid escape sequence (valid ones are \b \t \n \f \r \" \' \\ )' – Bhushan Sep 12 '13 at 12:44
Doh! Was in C# mode (where `@` before the string means you don't have to double-backslash). Just corrected by removing `@` and adding a backslash. – Steve Chambers Sep 12 '13 at 12:49

score 1 · Answer 2 · answered Sep 12 '13 at 12:36

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Pattern p = Pattern.compile("[\\[\\<](.*?)[\\]\\>]");
Matcher m = p.matcher("[[email protected]]");
System.out.println(m.matches());

answered Sep 12 '13 at 12:36

Farlan

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However, this'll also match ```[foo@bar>``` and vice versa. – Danstahr Sep 12 '13 at 12:40

Melih Altıntaş · Answer 3 · 2013-09-12T12:55:11.030

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firstly < or > are not special characters for regex so you don't have to use \

your regex should be like this :

"(<|\\])(.*?)\\1" but this regex does't check email adress is valid or not if you want to control email is valid or not you will use this regex :

"(<|\\])([\\w\\-]([\\.\\w])+[\\w]+@([\\w\\-]+\\.)+[A-Z]{2,4})\\1"

but you should not use regex for email validation

edited Sep 12 '13 at 12:55

answered Sep 12 '13 at 12:43

Melih Altıntaş

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Technically if a email address contains a `@` char and there is at least 1 char before and after the `@`, then its valid. Im not saying its an existing address just a possible valid address. http://tools.ietf.org/html/rfc2822#section-3.4.1 – string.Empty Sep 12 '13 at 13:22

score 1 · Answer 4 · answered Sep 12 '13 at 12:47

Use

Pattern p = Pattern.compile("^[_A-Za-z0-9-\\+]+(\\.[_A-Za-z0-9-]+)*@"+ "[A-Za-z0-9-]+(\\.[A-Za-z0-9]+)*(\\.[A-Za-z]{2,})$");
Matcher m = p.matcher("<[email protected]>");

Reference http://www.mkyong.com/regular-expressions/how-to-validate-email-address-with-regular-expression/

regex to check email ids

4 Answers4