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
No Match

/
/
gmx

Test String

Code Generator

Language

Generated Code

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "^(?:(?P<name>[\\p{L}\\.\\ ]+)\\n)?\n" + "(?:(?P<co>[\\p{L}\\.\\ \\/]+)\\n)?\n" + "(?P<street>[\\p{L}\\ \\p{N}’\\.]+)\\n\n" + "(?:(?<city>[\\p{L}\\ ]+)\\n)?\n" + "(?P<postal_code>[\\p{N}\\ ]+)\\ (?P<postal_city>[\\p{L}\\ ]+)(?:\\((?<province>[\\p{L}\\ ]+)\\))?\\n\n" + "(?P<country>[\\p{L}\\ ]+)?\n" + "$"; final String string = "Herr Franz Huber\n" + "Beethovenstrasse 12\n" + "1010 WIEN\n" + "AUSTRIA\n\n\n" + "Mr Willy Janssens\n" + "Lange Stationsstraat 352\n" + "3000 LEUVEN\n" + "BELGIUM\n\n\n" + "M. Emile Dubois\n" + "Rue du Diamant 215\n" + "4800 VERVIERS\n" + "BELGIUM\n\n\n" + "Mr Thor Nielsen\n" + "Tietgensgade 137\n" + "8800 VIBORG\n" + "DENMARK\n\n\n" + "Mr Torben Raldorf\n" + "PO Box 100\n" + "COPENHAGEN\n" + "1004 VIBORG\n" + "DENMARK\n\n\n" + "Peter Mogensen\n" + "c/o Fictional Company\n" + "Niels Bohrs Alle 23\n" + "Dalum\n" + "5230 Odense M\n" + "Danmark\n\n\n" + "Mr Asko Teirila\n" + "PO Box 511\n" + "39140 AKDENMAA\n" + "FINLAND\n\n\n" + "M. Robert MARIN\n" + "Rue de l’Eglise\n" + "Dunes\n" + "82340 AUVILLAR\n" + "FRANCE\n\n\n" + "Mme Marie PAGE\n" + "23 Rue de Grenell\n" + "75700 PARIS CEDEX\n" + "FRANCE\n\n\n" + "Mrs F Meier\n" + "Weberstr. 2\n" + "53113 BONNN\n" + "GERMANY\n\n\n" + "Mr P Kunde\n" + "Lange Str. 12\n" + "04103 LEIPZIG\n" + "GERMANY\n\n\n" + "Mr George Latsis\n" + "Alkamenou 37\n" + "117 80 ATHENS\n" + "GREECE\n\n\n" + "Mr Jon Jonsson\n" + "Einimel 80\n" + "107 REYKJAVIK\n" + "ICELAND\n\n\n" + "Sig. Giovanni Masci\n" + "via Garibaldi 27\n" + "47037 RIMINI RN\n" + "ITALY\n\n\n" + "M. Jaques Muller\n" + "71 route de Longway\n" + "4750 PETANGE\n" + "LUXEMBOURG\n\n\n" + "Mr J van Dieten\n" + "Morsstr 111\n" + "2312 BK LEIDEN\n" + "THE NETHERLANDS\n" + "(There should be a double space between the postcode and the post town)\n\n\n" + "Herr Hans Hansen\n" + "Svingen 22\n" + "9230 BEKKEHAUG\n" + "NORWAY\n\n\n" + "Senhor Carlos Manuel Pereira\n" + "Av das A’Augsa Livres\n" + "Monte Trigo\n" + "7220 PORTEL\n" + "PORTUGAL\n\n\n" + "Rosalina Silva\n" + "R Conde Redondo 80\n" + "1192 LISBOA CODEX\n" + "PORTUGAL\n\n\n" + "Sra Ana Jimenez\n" + "Mimbreras 4A\n" + "03201 ELCHE (Alicante)\n" + "SPAIN\n" + "(The province should be included in brackets after the town)\n\n\n" + "Fru Inger Lilja\n" + "Vasavagen 3 4tr\n" + "582 20 LINKOPING\n" + "SWEDEN\n\n\n" + "M. Andre Perret\n" + "Schanzenstrasse 7\n" + "3030 BERNE\n" + "SWITZERLAND"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE | Pattern.COMMENTS); 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