Java regular expression to validate email address that end with .services
Files found not to have valid Email addresses on a certain line are deleted: This piece of code has been working fine until one file appeared with an email Id : The file was deleted as one that does not have a valid Email address. Question: The Regular Expression to validate email address using is failing.
Java regular expression to validate email address that end with .services
The Regular Expression to validate email address using java.util.regex.Matcher is failing. It throws invalid email address or false.
How would i modify the pattern to allow email address that ends with .services
import java.util.regex.Matcher; import java.util.regex.Pattern; String emailAddress = myemail@something.services; public static Pattern EMAIL_PATTERN = Pattern.compile( "^[_A-Za-z0-9-]+(\\.[_A-Za-z0-9-]+)*@[A-Za-z0-9]+(\\.[A-Za-z0-9]+)*(\\.[A-Za-z])$"); Matcher matcher = ADDR_PATTERN.matcher(emailAddress); import java.util.regex.Matcher; import java.util.regex.Pattern; String emailAddress = myemail@something.services; public static Pattern EMAIL_PATTERN = Pattern.compile( "^[_A-Za-z0-9-]+(\\.[_A-Za-z0-9-]+)*@[A-Za-z0-9]+(\\.[A-Za-z0-9]+)*(\\.[A-Za-z])$"); Matcher matcher = ADDR_PATTERN.matcher(emailAddress); Rather than using regex, you should use the «built-in» javax.mail.internet.InternetAddress format validator. Regex becomes more complex as you add additional rules, whereas a basic validation and then a strict validation for the suffix is human-readable.
public static boolean isValidEmailAddress(String email) < try < InternetAddress emailAddr = new InternetAddress(email); emailAddr.validate(); //validates email format return true; >catch (AddressException ex) < return false; >> Pattern pattern = Pattern.compile("^[A-Z0-9._%+-]+@[A-Z0-9.-]+\\.services$", Pattern.CASE_INSENSITIVE); Matcher matcher = pattern.matcher("myemail@something.services"); System.out.println("result: "+matcher.find()); Using a regular expression with posix syntax to validate, Here is the validation that we have to use for email validation. i have failed to give right Email address to fulfill posix syntax regular expression. Could you please any one help me out to correct my below Java example. Java Example: import java.util.regex.Matcher; import java.util.regex.Pattern; public …
Java Regular Expressions
Introduction
Regular Expressions (RegEx) are a powerful tool and help us match patterns in a flexible, dynamic and efficient way, as well as to perform operations based on the results.
In this short guide, we’ll take a look at how to validate email addresses in Java with Regular Expressions .
If you’d like to read more about regular expressions and the regex package, read out Guide to Regular Expressions in Java!
Validating Email Addresses in Java
Validating Email Addresses isn’t hard — there’s not much diversity in the email world, though, there are a few ways you can go about it.
Regular expressions are expressive so you can add more and more constraints based on how you want to validate the emails, just by adding more matching rules.
Typically, you can boil things down to a pretty simple RegEx that will fit most email address patterns.
You can disregard the organization type ( .com , .org , .edu ), host ( gmail , yahoo , outlook ), or other parts of an email address, or even enforce them.
In the proceeding sections, we’ll take a look at a few different Regular Expressions, and which email formats they support or reject.
General-Purpose Email Regular Expression
The organizationtype is by convention, 3 characters — edu , org , com , etc. There are quite a few hosts, even custom ones, so really, this could be any sequence of characters — even aaa .
That being said, for pretty loose validation (but still a fully valid one) we can check whether the String contains 4 groups:
- Any sequence of characters — name
- The @ symbol
- Any sequence of characters — host
- Any 2-3-character letter sequence — organization type ( io , com , etc ).
This nets us a Regular Expression that looks like:
To additionally make sure they don’t contain any whitespaces at all, we can add a few \S checks:
That being said, to Validate an email address in Java, we can simply use the Pattern and Matcher classes:
String email = "[email protected]"; Pattern pattern = Pattern.compile("(\\S.*\\S)(@)(\\S.*\\S)(.\\S[a-z])"); Matcher matcher = pattern.matcher(email); if (matcher.matches()) < System.out.println("Full email: " + matcher.group(0)); System.out.println("Username: " + matcher.group(1)); System.out.println("Hosting Service: " + matcher.group(3)); System.out.println("TLD: " + matcher.group(4)); > Full email: [email protected] Username: someone Hosting Service: gmail TLD: com Alternatively, you can use the built-in matches() method of the String class (which just uses a Pattern and Matcher anyway):
String email = "[email protected]"; if(email.matches("(\\S.*\\S)(@)(\\S.*\\S)(.\\S[a-z])")) < System.out.println(String.format("Email '%s' is valid!", email)); > Email '[email protected]' is valid! Awesome! This general-purpose RegEx will take care of pretty much all generic input and will check whether an email follows the generic form that all emails follow.
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For the most part — this will work quite well, and you won’t need much more than this. You won’t be able to detect spam emails with this, such as:
However, you will enforce a certain form.
Note: To enforce certain hosts or domains, simply replace the .* and/or .[a-z] with actual values, such as gmail , io and .edu .
Robust Email Validation Regex
What does a robust email RegEx look like? Chances are — you won’t like it, unless you enjoy looking at Regular Expressions, which isn’t a particularly common hobby.
Long story short, this is what it looks like:
(?:[a-z0-9!#$%&'*+/=?^_`<|>~-]+(?:\.[a-z0-9!#$%&'*+/=^_`<|>~-]+)* |"(?:[\x01-\x08\x0b\x0c\x0e-\x1f\x21\x23-\x5b\x5d-\x7f] |\\[\x01-\x09\x0b\x0c\x0e-\x7f])*") @ (?:(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])? |\[(?:(?:(2(52|23) |141|1?3))\.)(?:(2(54|28) |111|6?9)|[a-z0-9-]*[a-z0-9]:(?:[\x01-\x08\x0b\x0c\x0e-\x1f\x21-\x5a\x53-\x7f] |\\[\x01-\x09\x0b\x0c\x0e-\x7f])+)\]) This is the RFC5322-compliant Regular Expression that covers 99.99% of input email addresses.*
Explaining it with words is typically off the table, but visualizing it helps a lot:
* Image and claim are courtesy of EmailRegex.com .
That being said, to create a truly robust email verification Regular Expression checker in Java, let’s substitute the loose one with this:
String email = "[email protected]"; Pattern pattern = Pattern.compile("(?:[a-z0-9!#$%&'*+/=?^_`<|>~-]+(?:\\.[a-z0-9!#$%&'*+/=?^_`<|>~-]+)*|\"(?:[\\x01-\\x08\\x0b\\x0c\\x0e-\\x1f\\x21\\x23-\\x5b\\x5d-\\x7f]|\\\\[\\x01-\\x09\\x0b\\x0c\\x0e-\\x7f])*\")@(?:(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?|\\[(?:(?:(2(51|35)|145|7?5))\\.)(?:(2(51|36)|171|6?8)|[a-z0-9-]*[a-z0-9]:(?:[\\x01-\\x08\\x0b\\x0c\\x0e-\\x1f\\x21-\\x5a\\x53-\\x7f]|\\\\[\\x01-\\x09\\x0b\\x0c\\x0e-\\x7f])+)\\])"); Matcher matcher = pattern.matcher(email); if (matcher.matches()) < System.out.println(String.format("Email '%s' is valid!", matcher.group(0))); > Needless to say — this works:
Email '[email protected]' is valid! This doesn’t check whether the email exists (can’t check that unless you try to send the email to the address) so you’re always stuck with that possibility. And of course, even this regex will note that odd Email Addresses such as:
Conclusion
In this short guide, we’ve taken a look at how to perform Email Validation in Java with Regular Expressions.
Any sort of validation really typically depends on your specific project, but there are some loose/general-purpose forms you can enforce and match for.
We’ve built a simple general-purpose form which will work most of the time, followed by a greatly robust Regular Expression as detailed by RFC5322.
Regex — regular expression for email validation in Java, If somebody wants to enter non-existent email address he’ll do it whatever format validation you choose. The only way to check that user owns email he entered is to send confirmation (or activation) link to that address and ask user to click it. So don’t try to make life of your users harder. Checking for …
Validating Email address using regex
I have been using this regex to validate email addresses. Files found not to have valid Email addresses on a certain line are deleted:
FileInputStream fsdel = new FileInputStream("C:/Folder/" + filefinal[o]); BufferedReader brdel = new BufferedReader(new InputStreamReader(fsdel)); for (int j = 0; j < 4; j++) < brdel.readLine(); >String email = brdel.readLine(); String mine = email.trim(); String lineIwant = mine.substring(0, 32).trim(); // System.out.println("EMAIL ID: " + lineIwant); String emailreg = "^[_A-Za-z0-9-]+(\\.[_A-Za-z0-9-]+)*@[A-Za-z0-9]+(\\.[A-Za-z0-9]+)*(\\.[A-Za-z])$"; Boolean b = lineIwant.matches(emailreg); if (b.toString() == "false") < System.out.println(filedel[o]); fsdel.close(); //brdel.close(); filedel[o].delete(); > This piece of code has been working fine until one file appeared with an email Id :
textsam.textsample@somedomain.co.uk The file was deleted as one that does not have a valid Email address. Can someone please help me on how to include the above email address as a valid one?
Why are you limiting the email address to 32 characters ? The above is 34 characters, but you limit it via
String lineIwant = mine.substring(0, 32).trim(); See also this SO question and the answers and this web page discussing email address regexps (it’s considerably more complicated than what you’re doing currently, and I would rethink your approach re. using regexps)
I believe you this is an error occurred due to limitation of characters. Always leave atleast 50 characters for an email address. My personal practice is 100, Also consider using Regular expressions inbuilt on the Microsoft visual studio, it should make things much easier for you.
Java — Regex email address validation, Validating email addresses is now considered bad practice ( stop validating email addresses with regex ), especially with such expression as in your question. For example here’s a more complete expression. As for this expression let’s break it in parts: Beginning of the matched string ^ Matches at least one character from the list Usage example(?:[A-Z]<2>|com|org|net|gov|mil|biz|info|mobi|name|in|aero|jobs|museum)Feedback