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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

/
/
sg

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 = "\\<(ol)(?: .*?)?\\>(?:[^\\<]|\\<(.*?)\\>.*\\<\\/\\2\\>)*\\<\\/\\1\\>"; final String string = "<ol>kjkjkj\n\n" + "</ol>\n\n\n\n" + "<ol s>\n" + " <li>Table of Contents.....................CT.TS</li>\n" + " <li>Gamecube Controls.....................CN.GC</li>\n" + " <li>Nintendo 64 Controls..................CN.64</li>\n" + " <li>Walkthrough...........................01.00\n" + " <ol>\n" + " <li>Kokiri Forest...............01.01</li>\n" + " </ol>\n" + " </li> \n" + " <li>Sidequests &amp; Minigames................02.00\n" + " <ol>\n" + " <li>Shooting Gallery............02.01</li>\n" + " </ol>\n" + " </li>\n" + " <li>Boss Guide............................03.00\n" + " <ol>\n" + " <li>Gohma.......................03.01</li>\n" + " <li>Final Boss [Second Form]....03.15</li>\n" + " </ol>\n" + " </li>\n" + " <li>Item Checklist........................04.00\n" + " <ol>\n" + " <li>Final Dungeon...............04.47</li>\n" + " </ol>\n" + " </li>\n" + " <li>Shop Inventory........................05.00 \n" + " <ol>\n" + " <li>Kokiri Shop [Young].........05.01</li>\n" + " <li>Goron Shop [Adult]..........05.09</li>\n" + " </ol>\n" + " </li>\n" + " <li>Ocarina Notes.........................06.00\n" + " <ol><ol>sdsds</ol>\n" + " <li>Requ<ol></ol>iem of Spirit...........06.12</li>\n" + " </ol>\n" + " </li>\n" + " <li>Heart Containers......................07.00</li>\n" + " <li>Item List.............................15.00</li>\n" + " <li>Legal &amp; Copyright.....................LE.AL</li>\n" + " <li>Credits &amp; Thanks......................CR.DS</li>\n" + " </ol>\n\n" + "<ol><ol><ol><ol><ol></ol></ol></ol></ol></ol>\n\n\n" + "sdsd\n" + "k<ol>jlkjlkj \n" + "kjbkjh</ol> "; final Pattern pattern = Pattern.compile(regex, Pattern.DOTALL); 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