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

/
/
gxi

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 = "[ptkmnlswj]?\n" + "(?:(?<=w)[aei]|\n" + "(?<=[jt])[aeou]|\n" + "(?<=[pkmnls])[aeiou]|\n" + "(?<=\\b)[aeiou])\n" + "(?:n(?![nm]?[aeiou]))?"; final String string = "#Sanity Checks:\n" + "---\n" + "toki pona\n" + "nanpa wan\n" + "toki li pona mama tuliwan sulisuli \n" + "mi olin e sina\n" + "---\n\n" + "#These should not work:\n" + "---\n" + "titijiji\n" + "tanna\n" + "nanma\n" + "---\n\n" + "#Some sentences from Wikipesija page for Linguistics:\n" + "---\n" + "toki Inli (kepeken toki Inli: EngLish) li toki suli.\n" + "toki Inli li kama tan ma Piten. taso tenpo ni la jan li kepeken kin e toki Inli lon ma Mewika lon ma Kanata lon ma Oselija lon ma Nusilan. jan li toki kin e toki Inli lon ma ante mute. toki Inli li toki pi ma sike. toki Inli li jo e kepeken mute.\n" + "---\n" + "a an e en i in o on u un\n" + "pa pan pe pen pi pin po pon pu pun\n" + "ta tan te ten ti tin to ton tu tun\n" + "ka kan ke ken ki kin ko kon ku kun\n" + "ma man me men mi min mo mon mu mun\n" + "na nan ne nen ni nin no non nu nun\n" + "sa san se sen si sin so son su sun\n" + "ja jan je jen ji jin jo jon ju jun\n" + "la lan le len li lin lo lon lu lun\n" + "wa wan we wen wi win wo won wu wun\n\n"; final Pattern pattern = Pattern.compile(regex, Pattern.COMMENTS | Pattern.CASE_INSENSITIVE); 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