Email validation using regular expression in JSF 2 / PrimeFaces

Question

I have an input field taking an email address:

<h:inputText value="#{register.user.email}" required="true" />

How can I validate the entered value as a valid email address using regex in JSF 2 / PrimeFaces?

score 53 · Answer 1 · answered Oct 10 '12 at 16:31

All regular expression attempts to validate the email format based on Latin characters are broken. They do not support internationalized domain names which were available since May 2010. Yes, you read it right, non-Latin characters are since then allowed in domain names and thus also email addresses.

That are thus extremely a lot of possible characters to validate. Best is to just keep it simple. The following regex just validates the email format based on the occurrence of the @ and . characters.

<f:validateRegex pattern="([^.@]+)(\.[^.@]+)*@([^.@]+\.)+([^.@]+)" />

Again, this just validates the general email format, not whether the email itself is legit. One can still enter aa@bb.cc as address and pass the validation. No one regex can cover that. If the validity of the email address is that important, combine it with an authentication system. Just send some kind of an activation email with a callback link to the email address in question and let the user login by email address.

an email k092167@nu.edu.pk is a valid email yet it is not validated by this regex pattern still +1 for the application — Anas, Apr 05 '14 at 12:01
Yeah maybe double backslashes would do, i copy pasted your regex and tried but it didnt work for only this email. — Anas, Apr 07 '14 at 05:34

score 46 · Accepted Answer · answered Oct 28 '11 at 17:03

46

Here is how:

Using it myself...

<h:inputText id="email" value="#{settingsBean.aFriendEmail}" required="true" label="Email" validatorMessage="#{settingsBean.aFriendEmail} is not valid">
    <f:validateRegex pattern="[\w\.-]*[a-zA-Z0-9_]@[\w\.-]*[a-zA-Z0-9]\.[a-zA-Z][a-zA-Z\.]*[a-zA-Z]" />
</h:inputText>
<p:message for="email" />

Daniel.

answered Oct 28 '11 at 17:03

Daniel

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how to update the above regex to make the valid domains only : .com,.net, .org, .edu ? also any ideas how to make this validation on focus lost ? – Mahmoud Saleh Sep 25 '12 at 15:04
3

Here is how : `` – Daniel Oct 03 '12 at 14:05
Doesn't work for a completely valid email containing plus sign, like name+surname@domain.com. – Igor Nov 11 '17 at 03:34

score 10 · Answer 3 · answered Oct 10 '12 at 14:51

10

Here's my version and it works well :

<f:validateRegex pattern="^[_A-Za-z0-9-\+]+(\.[_A-Za-z0-9-]+)*@[A-Za-z0-9-]+(\.[A-Za-z0-9]+)*(\.[A-Za-z]{2,})$" />

And i made a demo here

answered Oct 10 '12 at 14:51

mkyong

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score 1 · Answer 4 · answered Oct 19 '17 at 12:03

1

This one supports unicode domain names in email:

<f:validateRegex pattern="^[_A-Za-z0-9-\+]+(\.[_A-Za-z0-9-]+)*@[\p{L}\p{M}\p{N}.-]*(\.[\p{L}\p{M}]{2,})$" />

... and this one validates email only when email is entered (email is not required field in form):

<f:validateRegex pattern="(^[_A-Za-z0-9-\+]+(\.[_A-Za-z0-9-]+)*@[\p{L}\p{M}\p{N}.-]*(\.[\p{L}\p{M}]{2,})$)?" />

answered Oct 19 '17 at 12:03

Tere Hommikust

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The second one was very useful for me when the email is not required (optional) in form – Gabriel Patricio Bonilla Nov 14 '19 at 20:01

score 0 · Answer 5 · answered Sep 01 '19 at 04:35

<p:inputText id="email" required="true" label="email" size="40"
    requiredMessage="Please enter your email address."
    validatorMessage="Invalid email format"
    value="#{userBean.email}">

  <f:validateRegex
    pattern="^[_A-Za-z0-9-\+]+(\.[_A-Za-z0-9-]+)*@[A-Za-z0-9-]+(\.[A-Za-z0-9]+)*(\.[A-Za-z]{2,})$" />

</p:inputText>
<p:watermark for="email" value="Email Address *" />
<p:message for="email" />

<p:commandButton value="test" style="margin:20px"
    action="#{userBean.register}" ajax="false" />

Email validation using regular expression in JSF 2 / PrimeFaces

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