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 = "(America\\/Adak|America\\/Anchorage|America\\/Anguilla|America\\/Antigua|America\\/Araguaina|America\\/Argentina\\/Buenos_Aires|America\\/Argentina\\/Catamarca|America\\/Argentina\\/Cordoba|America\\/Argentina\\/Jujuy|America\\/Argentina\\/La_Rioja|America\\/Argentina\\/Mendoza|America\\/Argentina\\/Rio_Gallegos|America\\/Argentina\\/Salta|America\\/Argentina\\/San_Juan|America\\/Argentina\\/San_Luis|America\\/Argentina\\/Tucuman|America\\/Argentina\\/Ushuaia|America\\/Aruba|America\\/Asuncion|America\\/Atikokan|America\\/Bahia|America\\/Bahia_Banderas|America\\/Barbados|America\\/Belem|America\\/Belize|America\\/Blanc-Sablon|America\\/Boa_Vista|America\\/Bogota|America\\/Boise|America\\/Cambridge_Bay|America\\/Campo_Grande|America\\/Cancun|America\\/Caracas|America\\/Cayenne|America\\/Cayman|America\\/Chicago|America\\/Chihuahua|America\\/Ciudad_Juarez|America\\/Costa_Rica|America\\/Coyhaique|America\\/Creston|America\\/Cuiaba|America\\/Curacao|America\\/Danmarkshavn|America\\/Dawson|America\\/Dawson_Creek|America\\/Denver|America\\/Detroit|America\\/Dominica|America\\/Edmonton|America\\/Eirunepe|America\\/El_Salvador|America\\/Fort_Nelson|America\\/Fortaleza|America\\/Glace_Bay|America\\/Goose_Bay|America\\/Grand_Turk|America\\/Grenada|America\\/Guadeloupe|America\\/Guatemala|America\\/Guayaquil|America\\/Guyana|America\\/Halifax|America\\/Havana|America\\/Hermosillo|America\\/Indiana\\/Indianapolis|America\\/Indiana\\/Knox|America\\/Indiana\\/Marengo|America\\/Indiana\\/Petersburg|America\\/Indiana\\/Tell_City|America\\/Indiana\\/Vevay|America\\/Indiana\\/Vincennes|America\\/Indiana\\/Winamac|America\\/Inuvik|America\\/Iqaluit|America\\/Jamaica|America\\/Juneau|America\\/Kentucky\\/Louisville|America\\/Kentucky\\/Monticello|America\\/Kralendijk|America\\/La_Paz|America\\/Lima|America\\/Los_Angeles|America\\/Lower_Princes|America\\/Maceio|America\\/Managua|America\\/Manaus|America\\/Marigot|America\\/Martinique|America\\/Matamoros|America\\/Mazatlan|America\\/Menominee|America\\/Merida|America\\/Metlakatla|America\\/Mexico_City|America\\/Miquelon|America\\/Moncton|America\\/Monterrey|America\\/Montevideo|America\\/Montserrat|America\\/Nassau|America\\/New_York|America\\/Nome|America\\/Noronha|America\\/North_Dakota\\/Beulah|America\\/North_Dakota\\/Center|America\\/North_Dakota\\/New_Salem|America\\/Nuuk|America\\/Ojinaga|America\\/Panama|America\\/Paramaribo|America\\/Phoenix|America\\/Port-au-Prince|America\\/Port_of_Spain|America\\/Porto_Velho|America\\/Puerto_Rico|America\\/Punta_Arenas|America\\/Rankin_Inlet|America\\/Recife|America\\/Regina|America\\/Resolute|America\\/Rio_Branco|America\\/Santarem|America\\/Santiago|America\\/Santo_Domingo|America\\/Sao_Paulo|America\\/Scoresbysund|America\\/Sitka|America\\/St_Barthelemy|America\\/St_Johns|America\\/St_Kitts|America\\/St_Lucia|America\\/St_Thomas|America\\/St_Vincent|America\\/Swift_Current|America\\/Tegucigalpa|America\\/Thule|America\\/Tijuana|America\\/Toronto|America\\/Tortola|America\\/Vancouver|America\\/Whitehorse|America\\/Winnipeg|America\\/Yakutat)"; final String string = "America/Adak\n" + "America/Anchorage\n" + "America/Anguilla\n" + "America/Antigua\n" + "America/Araguaina\n" + "America/Argentina/Buenos_Aires\n" + "America/Argentina/Catamarca\n" + "America/Argentina/ComodRivadavia\n" + "America/Argentina/Cordoba\n" + "America/Argentina/Jujuy\n" + "America/Argentina/La_Rioja\n" + "America/Argentina/Mendoza\n" + "America/Argentina/Rio_Gallegos\n" + "America/Argentina/Salta\n" + "America/Argentina/San_Juan\n" + "America/Argentina/San_Luis\n" + "America/Argentina/Tucuman\n" + "America/Argentina/Ushuaia\n" + "America/Aruba\n" + "America/Asuncion\n" + "America/Atikokan\n" + "America/Atka\n" + "America/Bahia\n" + "America/Bahia_Banderas\n" + "America/Barbados\n" + "America/Belem\n" + "America/Belize\n" + "America/Blanc-Sablon\n" + "America/Boa_Vista\n" + "America/Bogota\n" + "America/Boise\n" + "America/Buenos_Aires\n" + "America/Cambridge_Bay\n" + "America/Campo_Grande\n" + "America/Cancun\n" + "America/Caracas\n" + "America/Catamarca\n" + "America/Cayenne\n" + "America/Cayman\n" + "America/Chicago\n" + "America/Chihuahua\n" + "America/Ciudad_Juarez\n" + "America/Coral_Harbour\n" + "America/Cordoba\n" + "America/Costa_Rica\n" + "America/Coyhaique\n" + "America/Creston\n" + "America/Cuiaba\n" + "America/Curacao\n" + "America/Danmarkshavn\n" + "America/Dawson\n" + "America/Dawson_Creek\n" + "America/Denver\n" + "America/Detroit\n" + "America/Dominica\n" + "America/Edmonton\n" + "America/Eirunepe\n" + "America/El_Salvador\n" + "America/Ensenada\n" + "America/Fort_Nelson\n" + "America/Fort_Wayne\n" + "America/Fortaleza\n" + "America/Glace_Bay\n" + "America/Godthab\n" + "America/Goose_Bay\n" + "America/Grand_Turk\n" + "America/Grenada\n" + "America/Guadeloupe\n" + "America/Guatemala\n" + "America/Guayaquil\n" + "America/Guyana\n" + "America/Halifax\n" + "America/Havana\n" + "America/Hermosillo\n" + "America/Indiana/Indianapolis\n" + "America/Indiana/Knox\n" + "America/Indiana/Marengo\n" + "America/Indiana/Petersburg\n" + "America/Indiana/Tell_City\n" + "America/Indiana/Vevay\n" + "America/Indiana/Vincennes\n" + "America/Indiana/Winamac\n" + "America/Indianapolis\n" + "America/Inuvik\n" + "America/Iqaluit\n" + "America/Jamaica\n" + "America/Jujuy\n" + "America/Juneau\n" + "America/Kentucky/Louisville\n" + "America/Kentucky/Monticello\n" + "America/Knox_IN\n" + "America/Kralendijk\n" + "America/La_Paz\n" + "America/Lima\n" + "America/Los_Angeles\n" + "America/Louisville\n" + "America/Lower_Princes\n" + "America/Maceio\n" + "America/Managua\n" + "America/Manaus\n" + "America/Marigot\n" + "America/Martinique\n" + "America/Matamoros\n" + "America/Mazatlan\n" + "America/Mendoza\n" + "America/Menominee\n" + "America/Merida\n" + "America/Metlakatla\n" + "America/Mexico_City\n" + "America/Miquelon\n" + "America/Moncton\n" + "America/Monterrey\n" + "America/Montevideo\n" + "America/Montreal\n" + "America/Montserrat\n" + "America/Nassau\n" + "America/New_York\n" + "America/Nipigon\n" + "America/Nome\n" + "America/Noronha\n" + "America/North_Dakota/Beulah\n" + "America/North_Dakota/Center\n" + "America/North_Dakota/New_Salem\n" + "America/Nuuk\n" + "America/Ojinaga\n" + "America/Panama\n" + "America/Pangnirtung\n" + "America/Paramaribo\n" + "America/Phoenix\n" + "America/Port-au-Prince\n" + "America/Port_of_Spain\n" + "America/Porto_Acre\n" + "America/Porto_Velho\n" + "America/Puerto_Rico\n" + "America/Punta_Arenas\n" + "America/Rainy_River\n" + "America/Rankin_Inlet\n" + "America/Recife\n" + "America/Regina\n" + "America/Resolute\n" + "America/Rio_Branco\n" + "America/Rosario\n" + "America/Santa_Isabel\n" + "America/Santarem\n" + "America/Santiago\n" + "America/Santo_Domingo\n" + "America/Sao_Paulo\n" + "America/Scoresbysund\n" + "America/Shiprock\n" + "America/Sitka\n" + "America/St_Barthelemy\n" + "America/St_Johns\n" + "America/St_Kitts\n" + "America/St_Lucia\n" + "America/St_Thomas\n" + "America/St_Vincent\n" + "America/Swift_Current\n" + "America/Tegucigalpa\n" + "America/Thule\n" + "America/Thunder_Bay\n" + "America/Tijuana\n" + "America/Toronto\n" + "America/Tortola\n" + "America/Vancouver\n" + "America/Virgin\n" + "America/Whitehorse\n" + "America/Winnipeg\n" + "America/Yakutat\n" + "America/Yellowknife\n"; 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