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

/
/
g

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 = "\\{\\$(\\w+|\\w+\\|\\w+)\\}"; final String string = "<!DOCTYPE html>\n" + "<html>\n" + "<head>\n" + " <meta charset=\"utf-8\">\n" + " <meta name=\"robots\" content=\"index,follow\">\n" + " <meta name=\"keywords\" content=\"kamerki, erotyczne\">\n" + " <meta name=\"description\" content=\"Eroticam.pl\">\n" + " <link rel=\"shortcut icon\" href=\"/favicon.ico\" type=\"image/x-icon\">\n" + " <title>Strona główna | Eroticam.pl</title>\n" + " <base href=\"{$_template_root|small_letters}\">\n" + " <meta property=\"og:url\" content=\"{$_template_root}\"/>\n" + " <meta property=\"og:site_name\" content=\"eroticam.pl\"/>\n" + " <meta property=\"og:title\" content=\"Strona główna | Eroticam.pl\"/>\n" + " <meta property=\"og:type\" content=\"profile\"/>\n" + " <meta property=\"og:image\" content=\"/img/logo_big.jpg\" />\n" + " <meta property=\"og:description\" content=\"Opis strony\"/>\n" + " \n" + " <script src=\"{$_template_root}/js/libs/console.js\"></script>\n" + " <script src=\"{$_template_root}/js/libs/broadcast.js\"></script>\n" + " <script src=\"https://cdn.socket.io/socket.io-1.3.5.js\"></script>\n" + " <script src=\"//ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js\"></script>\n" + " <script src=\"//ajax.googleapis.com/ajax/libs/jqueryui/1.10.4/jquery-ui.min.js\"></script>\n" + " <script src=\"{$_template_root}/js/jquery.fancybox.pack.js\"></script>\n" + " \n" + " <link rel=\"stylesheet\" href=\"{$_template_root}/css/components.css\">\n" + " <link rel=\"stylesheet\" href=\"{$_template_root}/css/default/style.css\">\n" + " <link rel=\"stylesheet\" href=\"{$_template_root}/css/default/responsive.css\">\n" + " <link rel=\"stylesheet\" href=\"{$_template_root}/css/jquery.fancybox.css\">\n" + " <link rel=\"stylesheet\" href=\"{$_template_root}/css/unoSlider.css\" type=\"text/css\" media=\"screen\" />\n" + " <link rel=\"stylesheet\" href=\"//ajax.googleapis.com/ajax/libs/jqueryui/1.10.4/themes/smoothness/jquery-ui.css\" />\n" + " \n" + " <meta name=\"viewport\" content=\"width=device-width, initial-scale=1\">\n" + " <meta name=\"google-site-verification\" content=\"1tqMv6H9GEsFbXTZaW8zcngUGvqorZ94csA1v7Nc2qg\" />\n" + "</head>\n" + "<body>"; final Pattern pattern = Pattern.compile(regex); 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