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

/
/
gm

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 = "^(?<pos>.{4})\\s(?<naam>.{25})\\s(?<plaats>.{25})\\s(?<tijd>.{8})"; final String string = " 25 Gerry Trimpe Middelburg 1:46:04\n" + " 26 Sylvia Glerum-witkam Delta Sport 1:46:35\n" + " 27 Annette de bot THOR 1:47:27\n" + " 28 Ernesta Verburg Dreischor 1:47:40\n" + " 29 Daniella Evers Middelburg 1:47:48\n" + " 30 Corine Poot Arnhem 1:48:05\n" + " 31 Lian Zorge Zierikzee 1:48:37\n" + " 32 Miranda Kwakkelaar Middelburg 1:50:42\n" + " 33 Lianne wijsman Delta Sport 1:51:17\n" + " 34 Esther Oldenburger Brielle 1:51:40\n" + " 35 Katinka Schotanus Kloetinge 1:51:47\n" + " 36 Heleen van der Linden PAC 1:52:04\n" + " 37 Cora Verheij Abbenbroek 1:54:22\n" + " 38 Connie Huibregtse Delta Sport 1:54:55\n" + " 39 Jacqueline Meijers AV '56 1:55:07\n" + " 40 Josien van Waarde Middelburg 1:55:52\n" + " 41 Liesbet Peeters Kasterlee 1:56:02\n" + " 42 Marianne zwart Helmond 1:56:41\n" + " 43 MariÎlle Lauwers Helmond 1:56:43\n" + " 44 Ieke de Jonge 's-Gravenhage 1:57:48\n" + " 45 Joke van Paassen Rockanje 1:58:00\n" + " 46 Mireille van der Veer Brielle 1:58:02\n" + " 47 Sylvia Verkaart Kapelle 1:58:33\n" + " 48 Lenneke Ruijsink AV '56 1:59:06\n" + " 49 Nicole Ehbel Steenbergen Nb 1:59:16\n" + " 50 Laila Heshof Steenbergen Nb 1:59:18\n" + " 51 Marleen Verboom Delta Sport 1:59:20\n" + " 52 Mandy Bootsma Strijen 2:00:16\n" + " 53 Debora Hampel- van Kapel Oud-Vossemeer 2:01:24\n" + " 54 Janneke van Westen Sint Philipsland 2:01:29\n" + " 55 Petra van den Doel Zierikzee 2:02:41\n" + " 56 Jolanda ter Steege Dinteloord 2:03:42\n" + " 57 Marleen Hozee Vlissingen 2:03:52\n" + " 58 Cynthia Janse Delta Sport 2:03:54\n" + " 59 Esther Brouwer Vlissingen 2:04:46\n" + " 60 Regine Boogert Middelburg 2:04:48\n" + " 61 Miriam Bijl Zuid-Beijerland 2:04:51\n" + " 62 Mariel Kers Dordrecht 2:18:43\n" + " 63 Pippi Langkous Scharendijke 2:23:26\n" + " 64 Monique Coppejans Nieuwdorp Zld 2:33:34"; 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