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

/
/
gmi

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 = "(^(HL\\/)+HL$)|(^HLx\\d+$)|(^HL$)"; final String string = "Guard\n" + "HL/H\n" + "-\n" + "HL/HL\n" + "L/L\n" + "L/L\n" + "HL/HL\n" + "L/HL\n" + "HL/HL\n" + "L/HL\n" + "HL/HL/HL\n" + "L/HL/HL\n" + "HL/HL\n" + "HL/HL/HL\n" + "HL/HL/HL/HL\n" + "HL/HL\n" + "HL/HL\n" + "HL/HL\n" + "HL/HL\n" + "HL/HL/HL\n" + "HL/HL/HL\n" + "HL/HL/HL\n" + "HL/HL\n" + "HL/HL\n" + "HL/HL\n" + "HL/HL\n" + "HL/HL/L/HL\n" + "HL/HL\n" + "HL/HL\n" + "HL/H\n" + "HL/HL\n" + "HL/HL\n" + "HL/HL\n" + "HL/HL\n" + "HL\n" + "HL/HL\n" + "HL/HL\n" + "HL/HL\n" + "HL\n" + "LH/LH\n" + "L/H\n" + "HL/HL\n" + "HL/HL\n" + "HL\n" + "LH/LH\n" + "L/H\n" + "HL/HL\n" + "HL/HL\n" + "HL/HL\n" + "HL/HL\n" + "HL/HL/HL\n" + "HL/HL/HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "(B+F)+LP+LK\n" + "(B/F)+LP+LK\n" + "LP+LK\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "L\n" + "HL\n" + "L\n" + "HL\n" + "HL\n" + "HL\n" + "L\n" + "L\n" + "L\n" + "L\n" + "L\n" + "L\n" + "HL\n" + "LP+LK\n" + "-\n" + "-\n" + "-\n" + "F/B+LP+LK\n" + "F+LP+LK\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "H\n" + "HL\n" + "LP+LK\n" + "B+LP+LK on backturned opponent\n" + "HL\n" + "LP+LK\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "H\n" + "B/F+LP+LK\n" + "LP+LK\n" + "LP+LK\n" + "LP+LK\n" + "LP+LK\n" + "LP+LK\n" + "LP+LK\n" + "=+\n" + "=+\n" + "LP+LK\n" + "H\n" + "H\n" + "HL\n" + "HL\n" + "HL\n" + "LP+LK\n" + "HL\n" + "HL\n" + "HL\n" + "LP+LK\n" + "HL\n" + "HL\n" + "L\n" + "HL\n" + "L\n" + "L\n" + "HL\n" + "LP+LK\n" + "HLx2\n" + "HL\n" + "HL\n" + "HL\n" + "B+LP+LK\n" + "B/F+LP+LK\n" + "B/F+LP+LK\n" + "B/F+LP+LK\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "LP+LK\n" + "Close to Oponnent On Air LP+LK\n" + "LP+LK\n" + "(F)+LP+LK\n" + "HL/HL/HL\n" + "HL\n" + "HL/HL\n" + "HL\n" + "LP+LK\n" + "HL\n" + "HL\n" + "HL\n" + "L\n" + "L\n" + "L\n" + "LP+LK\n" + "HL\n" + "HL\n" + "HL\n" + "B+LP+LK\n" + "HL\n" + "HL\n" + "(Air) LP+LK\n" + "LP+LK\n" + "LP+LK\n" + "B+LP+LK\n" + "LP+LK\n" + "HL\n" + "HL\n" + "HL\n" + "LP+LK\n" + "(B/F)+LP+LK\n" + "H\n" + "F+LP+LK\n" + "HL\n" + "H/H\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL/HL\n" + "HL/HL/HL\n" + "HL/HL/HL\n" + "HL\n" + "HL\n" + "HL\n" + "HLx7\n" + "HL/HL/HL\n" + "HLx4\n" + "HLx3+HL/Lx3 Down\n" + "HL/HL/HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "H\n" + "H\n" + "HL\n" + "HL\n" + "HL\n" + "L\n" + "H\n" + "H\n" + "HL\n" + "Impossible\n" + "HL\n" + "H\n" + "HL\n" + "HL\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "HL\n" + "HL\n" + "HL\n" + "H\n" + "HL\n" + "HL\n" + "HL\n" + "L\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "H\n" + "H\n" + "H\n" + "H\n" + "HL\n" + "H\n" + "HL\n" + "Impossible\n" + "HL\n" + "HL\n" + "HL\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "HL\n" + "HL/HL\n" + "HL\n" + "H\n" + "HL\n" + "HL\n" + "H\n" + "H\n" + "H\n" + "HL\n" + "H\n" + "HL\n" + "L\n" + "H\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "H\n" + "HL\n" + "HL\n" + "H\n" + "H\n" + "H\n" + "HL/HL\n" + "HL\n" + "-\n" + "HL\n" + "H\n" + "H\n" + "HL\n" + "HL\n" + "HL/HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "Impossible\n" + "Impossible\n" + "Impossible\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "L\n" + "L\n" + "L\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "L\n" + "L\n" + "L\n" + "L\n" + "L\n" + "L\n" + "L\n" + "L\n" + "L\n" + "L\n" + "L\n" + "HL\n" + "L\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "L\n" + "L\n" + "L\n" + "L\n" + "HLx1~5\n" + "HLx1~5\n" + "HLx1~5\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "L\n" + "L\n" + "L\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "Impossible\n" + "HL\n" + "H\n" + "H\n" + "H\n" + "HL\n" + "HL\n" + "Impossible\n" + "Impossible\n" + "Impossible\n" + "Impossible\n" + "Impossible\n" + "Impossible\n" + "H\n" + "H\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "L\n" + "L\n" + "L\n" + "L\n" + "HL/HL/HL\n" + "HL/HL\n" + "Impossible\n" + "Impossible\n" + "Impossible\n" + "HL\n" + "Impossible\n" + "Impossible\n" + "Impossible\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "Hx2\n" + "HL\n" + "Hx2\n" + "HL\n" + "HL\n" + "HL\n" + "H\n" + "HLx4\n" + "HL\n" + "HL\n" + "HLx3\n" + "HL\n" + "L/HL\n" + "HL/HL\n" + "HL\n" + "H\n" + "HLx2\n" + "HL/HL\n" + "HL/HL\n" + "HL/HL\n" + "HL/HL\n" + "HL/HL\n" + "HL/HL\n" + "HL\n" + "HLx2\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "H/H\n" + "H\n" + "HL/HL\n" + "HL/HL/HL\n" + "HL\n" + "HL\n" + "HL/HL/HL\n" + "HL/H\n" + "L\n" + "HL/HL\n" + "HL\n" + "H\n" + "H\n" + "H(far) or L(close)\n" + "H\n" + "HLx2\n" + "HL\n" + "HL\n" + "HL\n" + "-\n" + "HL\n" + "HL/HL/HL\n" + "HL/HL/HL\n" + "H\n" + "HL/HL/HL/HL\n" + "HL/HL/HL/HL/HL\n" + "H\n" + "HL/HL/HL\n" + "HL\n" + "HL/HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "H/H\n" + "H/H\n" + "H/H\n" + "H\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "L\n" + "L\n" + "L\n" + "L\n" + "L\n" + "L\n" + "L\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "L\n" + "L\n" + "L\n" + "L\n" + "L\n" + "L\n" + "L\n" + "L\n" + "L\n" + "L\n" + "H\n" + "HL\n" + "HL\n" + "H\n" + "H\n" + "H\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "H\n" + "HL/HL/HL/HL\n" + "HL/HL/HL/HL/HL\n" + "HL/HL\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "-\n" + "HL\n" + "HL\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "L\n" + "HL/HL/HL/HL\n" + "-\n" + "H\n" + "HLx4\n" + "H\n" + "H\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "H/H\n" + "H/H\n" + "H/H\n" + "Lx2\n" + "Lx4\n" + "Lx2\n" + "HL\n" + "HL\n" + "HL/HL\n" + "H/L\n" + "-\n" + "-\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "L\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "L\n" + "L\n" + "L\n" + "L\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL/HL\n" + "H\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "H\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "-\n" + "-\n" + "HL\n" + "HL/H/H\n" + "HL\n" + "H\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "H/H\n" + "H\n" + "HLx2\n" + "HLx1~5\n" + "HL/HL/HL\n" + "HL/HL\n" + "HL/HL\n" + "HL/HL\n" + "HL/HL\n" + "HL\n" + "H\n" + "HL/H/H\n" + "-\n" + "HL\n" + "Lx5\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "L\n" + "L\n" + "L\n" + "L\n" + "L\n" + "L\n" + "L\n" + "L\n" + "L\n" + "L\n" + "L\n" + "HL\n" + "HL\n" + "HL\n" + "H\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "HL\n" + "HLx2\n" + "H\n" + "HL\n" + "HL\n" + "H\n" + "-\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HLx2\n" + "HLx2\n" + "HLx2\n" + "HLx3\n" + "HLx3\n" + "HLx3\n" + "-\n" + "-\n" + "-\n" + "HL\n" + "HL\n" + "L\n" + "HL\n" + "HL\n" + "HL/HL/HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL/HL\n" + "HL\n" + "HL\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "HL/H/H\n" + "HL\n" + "HL\n" + "HL\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "H\n" + "HL\n" + "HL\n" + "HL\n" + "HLx2\n" + "HL/HL/HL\n" + "HLx2\n" + "HL\n" + "HLx2\n" + "HL/HL\n" + "HL\n" + "HLx2\n" + "Hx3\n" + "HL\n" + "H\n" + "H\n" + "H\n" + "-\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL/HL/HL\n" + "HL\n" + "HL\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "H/H\n" + "HL\n" + "HL\n" + "HLx2\n" + "L\n" + "L\n" + "HL\n" + "H\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "HL\n" + "L\n" + "H\n" + "H\n" + "H\n" + "H\n" + "HL\n" + "HL\n" + "HL\n" + "HLx2\n" + "HL\n" + "HL\n" + "H\n" + "Impossible\n" + "HL\n" + "H\n" + "H\n" + "H\n" + "HLx2\n" + "H\n" + "H\n" + "HL\n" + "HL\n" + "HL\n" + "HL\n" + "H\n" + "HL\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "H\n" + "HL\n" + "H\n" + "H\n" + "H\n" + "-\n" + "H\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE | 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