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

/
/
gx

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 = "(?(DEFINE)\n" + " (?<groupStart> <g )\n" + " (?<groupAttrs> >|[^>]+> )\n" + " (?<groupStartContainer> (?:(?&groupStart)(?&groupAttrs)(?&space)){1,} )\n" + " (?<groupEnd> (?:<\\/g>(?&space)){1,} )\n" + " (?<group> (?:(?&groupStartContainer)(?&tags)){1,}(?&groupEnd)(?:(?&space)(?&tags)(?&groupEnd))? )\n" + " (?<tags> (?:<[^>]+\\/>(?&space)){1,} )\n" + " (?<space> (?:\\s+)? )\n" + ")\n" + "(?<groupeSimples> (?&group) )"; final String string = "<g id=\"Tie2\"> <path fill=\"#402A23\" d=\"M21,2.307c0,1.809,0,3.016,0,3.016s0.057,1.809-1.752,1.809l0.178,0.682l-5.027,5.042l1.342-5.723 c0,0-1.741,0-1.741-1.809c0-1.809,0-3.016,0-3.016S13.876,1,15.686,1s3.618,0,3.618,0S21,0.498,21,2.307z\"/> <polygon fill=\"#402A23\" points=\"20.993,14.717 12.001,23.709 13.684,16.14 19.919,9.905 \"/> <polygon fill=\"#402A23\" points=\"22.855,23.106 14.305,31.657 10.861,28.841 11.271,26.996 21.457,16.81 \"/> <polygon fill=\"#402A23\" points=\"24.128,28.841 17.495,34.269 15.709,32.809 23.32,25.198 \"/> </g> <path id=\"TV\" fill=\"#402A23\" d=\"M32.154,8.083H17.152l4.972-5.813l-1.649-1.406l-5.688,6.633L9.098,0.863L7.447,2.27l4.972,5.813 c-5.297,0-9.574,0-9.574,0s-2.171,0-2.171,2.171v19.541c0,0,0,2.17,2.171,2.17h3.257v2.172h3.257v-2.172h16.283v2.172h3.257v-2.172 c1.997,0,3.256,0,3.256,0s2.172,0,2.172-2.17V10.254C34.326,10.254,34.326,8.083,32.154,8.083z M23.47,26.538 c0,0,0,2.171-2.171,2.171s-15.197,0-15.197,0s-2.171,0-2.171-2.171c0-2.172,0-13.027,0-13.027s0-2.171,2.171-2.171 s15.197,0,15.197,0s2.171,0,2.171,2.171C23.47,15.682,23.47,26.538,23.47,26.538z M28.355,25.452c-0.901,0-1.629-0.728-1.629-1.629 c0-0.9,0.728-1.628,1.629-1.628s1.628,0.728,1.628,1.628C29.983,24.725,29.257,25.452,28.355,25.452z M31.069,20.023h-5.428v-2.17 h5.428V20.023z M31.069,15.682h-5.428v-2.171h5.428V15.682z\"/> <g id=\"Typewriter\"> <g> <path fill=\"#402A23\" d=\"M26.328,12.455v3.783H8.672v-3.783H4.888v16.396h25.223V12.455H26.328z M18.762,17.5h2.521v2.522h-2.521 V17.5z M18.762,21.283h2.521v2.522h-2.521V21.283z M13.717,17.5h2.522v2.522h-2.522V17.5z M13.717,21.283h2.522v2.522h-2.522 V21.283z M8.672,17.5h2.522v2.522H8.672V17.5z M8.672,21.283h2.522v2.522H8.672V21.283z M23.807,27.169H11.194v-2.102h12.612 V27.169z M26.328,23.806h-2.521v-2.522h2.521V23.806z M26.328,20.022h-2.521V17.5h2.521V20.022z\"/> </g> <rect x=\"9.933\" y=\"6.149\" fill=\"#402A23\" width=\"15.133\" height=\"8.828\"/> <rect x=\"1.105\" y=\"11.194\" fill=\"#402A23\" width=\"2.522\" height=\"5.044\"/> <rect x=\"31.373\" y=\"11.194\" fill=\"#402A23\" width=\"2.521\" height=\"5.044\"/> </g> <g id=\"capa\"> <path fill=\"#402A23\" d=\"M27.873,10.156L6.395,9.743c-3.322-0.064-4.033,2.12-4.077,4.438L2.117,24.654l2.607,0.003l0.202-10.474 C4.938,13.469,5.531,12.986,6.247,13l5.218,0.1l-0.226,11.73l1.304,0.025l0.225-11.729l3.91,0.075l-0.225,11.73l1.303,0.024 l0.226-11.729l9.123,0.175L26.88,25.13l1.303,0.025l0.226-11.713c1.101,0.351,1.275,1.467,1.255,2.52l-0.177,9.218l3.258,0.062 l0.178-9.217C32.982,12.886,30.478,10.205,27.873,10.156z\"/> <rect x=\"6.138\" y=\"13.012\" transform=\"matrix(-0.9998 -0.018 0.018 -0.9998 13.2402 37.8739)\" fill=\"#402A23\" width=\"1.304\" height=\"11.732\"/> <rect x=\"8.745\" y=\"13.06\" transform=\"matrix(-0.9998 -0.0195 0.0195 -0.9998 18.424 38.033)\" fill=\"#402A23\" width=\"1.303\" height=\"11.733\"/> <rect x=\"13.959\" y=\"13.161\" transform=\"matrix(-0.9998 -0.0195 0.0195 -0.9998 28.8478 38.3347)\" fill=\"#402A23\" width=\"1.303\" height=\"11.732\"/> <rect x=\"19.172\" y=\"13.262\" transform=\"matrix(-0.9998 -0.0187 0.0187 -0.9998 39.2856 38.623)\" fill=\"#402A23\" width=\"1.303\" height=\"11.731\"/> <rect x=\"24.385\" y=\"13.361\" transform=\"matrix(-0.9998 -0.0195 0.0195 -0.9998 49.6941 38.9389)\" fill=\"#402A23\" width=\"1.304\" height=\"11.733\"/> <rect x=\"21.778\" y=\"13.311\" transform=\"matrix(-0.9998 -0.0195 0.0195 -0.9998 44.4827 38.7881)\" fill=\"#402A23\" width=\"1.304\" height=\"11.733\"/> </g> <g id=\"Typewriter2\"> <rect x=\"9.933\" y=\"6.149\" fill=\"#402A23\" width=\"15.133\" height=\"8.828\"/> <rect x=\"1.105\" y=\"11.194\" fill=\"#402A23\" width=\"2.522\" height=\"5.044\"/> <rect x=\"31.373\" y=\"11.194\" fill=\"#402A23\" width=\"2.521\" height=\"5.044\"/> <g> <path fill=\"#402A23\" d=\"M26.328,12.455v3.783H8.672v-3.783H4.888v16.396h25.223V12.455H26.328z M18.762,17.5h2.521v2.522h-2.521 V17.5z M18.762,21.283h2.521v2.522h-2.521V21.283z M13.717,17.5h2.522v2.522h-2.522V17.5z M13.717,21.283h2.522v2.522h-2.522 V21.283z M8.672,17.5h2.522v2.522H8.672V17.5z M8.672,21.283h2.522v2.522H8.672V21.283z M23.807,27.169H11.194v-2.102h12.612 V27.169z M26.328,23.806h-2.521v-2.522h2.521V23.806z M26.328,20.022h-2.521V17.5h2.521V20.022z\"/> </g> </g>\n"; final Pattern pattern = Pattern.compile(regex, 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