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

r"
"
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 = "\\b(?:a*(?:ha*){2,}h?)\\b|\\b(?:a*(?:ja*)+j?)\\b|\\b(?:e*(?:je*)+j?)\\b|\\b(?:i*(?:ji+)+j?)\\b|\\b(?:A*(?:JA+)+J?)\\b|\\b(?:A*(?:HA+)+H?)\\b|\\b(?:e*(?:he+){2,}h?)\\b|\\b(?:Ja*(?:ja+)+j?)\\b|\\b(?:Je*(?:je+)+j?)\\b|\\bJa+\\b|\\b(?:Ji*(?:ji+)+j?)\\b|\\b(?:Ha*(?:ha+)+h?)\\b|\\b(?:Jo*(?:jo+)+j?)\\b|\\b(?:o*(?:jo+)+j?)\\b|\\b(?:a*((?:ja+)|(?:js+))+j?)\\b|\\b(?:A*((?:JA+)|(?:JS+))+J?)\\b"; final String string = "jajajajajaja\n" + "jejejejeje\n" + "jijijijijij\n" + "ji\n" + "ja\n" + "je\n" + "hahahahahahaaaaa\n" + "Hahahaaa\n" + "Hahaaahaaha\n" + "hahaahaaaah\n" + "haaaaahaaahahahaaaaah\n" + "heheeheheeeeheeeheh\n" + "jajajaj\n" + "jaja\n" + "ja\n" + "jejejej\n" + "jeje\n" + "je\n" + "jijijiji\n" + "jiji\n" + "ji\n" + "ajajajaja\n" + "ahahahaha\n" + "ejejejeje\n" + "aaajajaja\n" + "jajaaajajaaajaaaa\n" + "JAJAJAJAJAJAJAJ\n" + "HAHAHAHAAAAHAHAHAHAAA\n" + "Hahahahahaha\n" + "JAJAJAJA\n" + "AAJAJAJA\n" + "JAJAAAJAJAJAAAAJ\n" + "he \n" + "hehe\n" + "haha\n" + "ha \n" + "has \n" + "hamaca \n" + "Jajajajaja\n" + "Jaja\n" + "Jejejejejeje\n" + "Jaa\n" + "Jijijijiiiiji\n" + "jiiijijijiiijijijiii \n" + "Jojojojojoj\n" + "jojojoj \n" + "Hahaa \n" + "Jejeee\n" + "jajaaaa\n" + "Jajaaaa\n" + "jajaj\n" + "jajajajsjaja\n" + "jajajssjsjsjajsja\n" + "jsjsjsjsjsjsj\n" + "JAJAJSJAJSSJAJSJSJAJSSSSJ \n"; 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