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

/
/
gm

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 = "^(?<numberExpression>(?<numberDice>[0-9]+)(?<gaussExpression>[oO]?(?<gaussDices>[0-9])+(?<gaussModifier>[\\+\\-])?)?)?[dD](?<faces>[0-9]+)(?<exploding>[¡!]{0,2})(?<modifierExpression>[\\+\\-](?<modifierValue>[0-9]+))?(?<thresholdExp>:(?<thresholdValue>[0-9]+))?"; final String string = "Common dice:\n" + "1d2 (coin flip)\n" + "2d4\n" + "3d6\n" + "4d8\n" + "5d10\n" + "6d12\n" + "7d20\n" + "8d30\n" + "9d100\n\n" + "Gauss notation:\n" + "1o3d10 Basic notation\n" + "1o3+d10 Gauss with gauss-modifier\n" + "1o3-d10 Gauss with gauss-modifier\n" + "1o5d8 Gauss with other configurations\n\n" + "Exploding dice:\n" + "1d10! Exploding\n" + "1d10¡ Imploding\n" + "1d10!¡ Both, exploding and imploding\n" + "1d10¡! Another possible arrangement\n" + "1o3d10! Gauss exploding\n\n" + "Adding and substracting:\n" + "1d10+20\n" + "1d10-3 \n" + "1o3d10+3 Gauss with modifiers\n" + "1o3d10!-3 Gauss with exploding dice and modifiers\n\n" + "Threshold:\n" + "1d10:6\n" + "1d10+2:8 Modifier and threshold\n" + "1d10!+1:8 Exploding, modifier and threshold\n" + "1o3+d10!+3:8 Gauss with gauss-modifier, exploding option, modifier and threshold"; 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