Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression

/
/
mg

Test String

Code Generator

Generated Code

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "^(?=.*(\\.((?![^\\.]$)[^\\.]*)$)|.*@(?:(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)$))(?=^.{6,320}$)(?:[a-zA-Z0-9áàâäãåçéèêëíìîïñóòôöõúùûüýÿæœÁÀÂÄÃÅÇÉÈÊËÍÌÎÏÑÓÒÔÖÕÚÙÛÜÝŸÆŒ!#$%&'*+\\/=?^_`\\{|\\}~-]+(?:\\.[a-zA-Z0-9áàâäãåçéèêëíìîïñóòôöõúùûüýÿæœÁÀÂÄÃÅÇÉÈÊËÍÌÎÏÑÓÒÔÖÕÚÙÛÜÝŸÆŒ!#$%&'*+\\/=?^_`\\{|\\}~-]+)*|\"(?:[\\xE1\\xE0\\xE2\\xE4\\xE3\\xE5\\xE7\\xE9\\xE8\\xEA\\xEB\\xED\\xEC\\xEE\\xEF\\xF1\\xF3\\xF2\\xF4\\xF6\\xF5\\xFA\\xF9\\xFB\\xFC\\xFD\\xFF\\xE6\\xC1\\xC0\\xC2\\xC4\\xC3\\xC5\\xC7\\xC9\\xC8\\xCA\\xCB\\xCD\\xCC\\xCE\\xCF\\xD1\\xD3\\xD2\\xD4\\xD6\\xD5\\xDA\\xD9\\xDB\\xDC\\xDD\\xC6\\x01-\\x08\\x0b\\x0c\\x0e-\\x1f\\x21\\x23-\\x5b\\x5d-\\x7f\\s]|\\\\[\\x01-\\x09\\x0b\\x0c\\x0e-\\x7f])*\")(?:(?=@(?:[0-9]{1,3}.){3}[0-9]{1,3})@(?:(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?))$|(?!@(?:[0-9]{1,3}.){4,}$)@(?:(?:[a-zA-Z0-9áàâäãåçéèêëíìîïñóòôöõúùûüýÿæœÁÀÂÄÃÅÇÉÈÊËÍÌÎÏÑÓÒÔÖÕÚÙÛÜÝŸÆŒ](?:[a-zA-Z0-9áàâäãåçéèêëíìîïñóòôöõúùûüýÿæœÁÀÂÄÃÅÇÉÈÊËÍÌÎÏÑÓÒÔÖÕÚÙÛÜÝŸÆŒ-]*[a-zA-Z0-9áàâäãåçéèêëíìîïñóòôöõúùûüýÿæœÁÀÂÄÃÅÇÉÈÊËÍÌÎÏÑÓÒÔÖÕÚÙÛÜÝŸÆŒ])?\\.)+[a-zA-Z0-9áàâäãåçéèêëíìîïñóòôöõúùûüýÿæœÁÀÂÄÃÅÇÉÈÊËÍÌÎÏÑÓÒÔÖÕÚÙÛÜÝŸÆŒ](?:[a-zA-Z0-9áàâäãåçéèêëíìîïñóòôöõúùûüýÿæœÁÀÂÄÃÅÇÉÈÊËÍÌÎÏÑÓÒÔÖÕÚÙÛÜÝŸÆŒ-]*[a-zA-Z0-9áàâäãåçéèêëíìîïñóòôöõúùûüýÿæœÁÀÂÄÃÅÇÉÈÊËÍÌÎÏÑÓÒÔÖÕÚÙÛÜÝŸÆŒ])?)$)"; final String string = "jeu de test invalides\n" + "-----------\n" + "a@123.123.123.123.123\n" + "a@123.123.123.123.5\n" + "a@222.333.666.888\n" + "a@322.111.222.001\n" + "a@29.99.352.001\n" + "a@124.124.14..124\n" + "a@a.f\n" + "a@.fr\n" + "adresse.de.321.caracteres@bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa@bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb.bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb.cccccccccc\n" + ".bds@finances.gouv.fr.edu.com\n" + "bds.@finances.gouv.fr.edu.com\n\n\n" + "jeu de test valides\n" + "-----------\n" + "a@222.111.11.2.tutu.com\n" + "a@222.111.11.333.com\n" + "a@222.111.com\n" + "a@22d2.11d1.com\n" + "a@29.99.252.001\n" + "a@022.111.222.001\n" + "a@124.124.124.124\n" + "a@111.111.111.111\n" + "a@222.5.22.001\n" + "této@194.168.12.5\n" + "abc@a.b.c.azertyuiop\n" + "a@b.fr\n" + "\"Abc@def\"@example.com\n" + "def@example.com\n" + "a@b.com\n" + "abc@b.fr\n" + "abc@a.b.c.fr\n" + "abc@a.b.c.azertyuiop\n" + "a@b.fr\n" + "baltazar.da-silva@douane.finances.gouv.fr\n" + "toto@titi.fr\n" + "tôto@tïtié.fr\n" + "\"tôto\"@tïtié.fr\n" + "\"áàâäãåçéèêëíìîïñóòôöõúùûüýÿæÁÀÂÄÃÅÇÉÈÊËÍÌÎÏÑÓÒÔÖÕÚÙÛÜÝÆ\"@titiéà.fr\n" + "\"této\"@titiéà.fr\n" + "\"tàto\"@titiéà.fr\n" + "\"t to\"@titiéà.fr\n" + "této@titiéà.fr\n" + "této@194.168.12.5\n" + "customer/department=shipping@example.com\n" + "$A12345@example.com\n" + "!def!xyz%abc@example.com\n" + "_somename@example.com\n" + "Loïc.Accentué@voilà.fr3"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE); final Matcher matcher = pattern.matcher(string); while (matcher.find()) { System.out.println("Full match: " + matcher.group(0)); for (int i = 1; i <= matcher.groupCount(); i++) { System.out.println("Group " + i + ": " + matcher.group(i)); } } } }

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Java, please visit: https://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html