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

/
/
gm

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 = "^((?![0-9.,!?:;_|+\\-*\\\\/=%°@&#§$\"'`¨^ˇ()\\[\\]<>\\{\\}])[\\S])+$"; final String string = "Vit5\n" + "V.it\n" + ".Vit\n" + "Vit.\n" + "Vit\\\\\n" + "V|it\n" + "Vi-t\n" + "V+it\n" + "+Vit\n" + "Vit^\n" + "V^it\n" + "V&it\n" + "Vi#t\n" + "Vi@t\n" + "Vit \n" + " Vit\n" + "V it\n" + "Vi)t\n" + "V(it\n" + "Vi[t\n" + "Vi]t\n" + "V?it\n" + "V!it\n" + "V$it\n" + "V*it\n" + "Vi{t\n" + "Vi}t\n" + "V<it\n" + "Vi>t\n" + "Vi_t\n" + "V-it\n" + "Vi=t\n" + "Vi%t\n" + "ˇVit\n" + "V;it\n" + "V\\\"it\n" + "V'it\n" + "V§t\n" + "V¨t\n" + "V`t\n\n" + "Dopita\n" + "Václav\n" + "Átos\n" + "Čeněk\n" + "Pačáp\n" + "Ďurica\n" + "Naďa\n" + "Rémi\n" + "Zdeněk\n" + "Vít\n" + "Ľudovít\n" + "Ňouma\n" + "Ňuňu\n" + "Lórenc\n" + "Ópava\n" + "Mótovidlo\n" + "Řeřicha\n" + "Šušinka\n" + "Ťaťak\n" + "Úlehlú\n" + "Ůlehlů\n" + "Ýtý\n" + "Žežulka"; 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