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

/
/
gis

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 = "^(?:[[:^print:][:cntrl:]\\s]|GIF89.{0,20})*(?:<[^>]+>\\s*)+<title>contador\\s*de \\s*acessos<\\/title>.{0,1350}?\\$caminho\\s*=\\s*\"contador\\.txt.{0,150}?\\$arquivo\\s*=\\s*fopen\\(\\$caminho.{0,150}?numero\\s*de\\s*visitas\\s*fclose\\(\\$arquivo.{0,650}?<meta.{0,50}?url=['\"]contador\\.php.{0,50}?\\/html[[:punct:]\\s]+$"; final String string = "<html>\n" + "<head>\n" + "<title>Contador de Acessos</title>\n" + "<meta http-equiv=\"Content-Type\" content=\"text/html; charset=iso-8859-1\"><style type=\"text/css\">\n" + "<!--\n" + "body,td,th {\n" + " color: #FF0000;\n" + " font-family: Verdana;\n" + " font-size: 12px;\n" + "}\n" + "body {\n" + " background-color: #CCCCCC;\n" + "}\n" + ".style1 {\n" + " font-size: 15px;\n" + " font-weight: bold;\n" + "}\n" + ".style2 {\n" + " font-size: 12px;\n" + " color: #FF0000;\n" + "}\n" + ".style3 {\n" + " font-size: 15px;\n" + " color: #000000;\n" + "}\n" + ".style4 {color: #000000}\n" + ".style5 {font-size: 15px; font-weight: bold; color: #000000; }\n" + ".style8 {font-size: 24px; font-weight: bold; }\n" + ".style9 {color: #CCCCCC}\n" + ".style11 {color: #FF0000}\n" + ".style12 {color: #FFFFFF}\n" + ".style15 {color: #FFFFFF; font-size: 20px; }\n" + "-->\n" + "</style><body link=\"#FF0000\" vlink=\"#FF0000\" alink=\"#FF0000\">\n" + "<center>\n" + " <table width=\"476\" border=\"0\">\n" + " <tr>\n" + " <td width=\"470\" bgcolor=\"#000000\"><div align=\"center\"><span class=\"style15\"> CONTADOR - <span class=\"style11\">BB</span></span> </div></td>\n" + " </tr>\n" + " </table>\n" + " <p><span class=\"style5\"> $$ CONTADOR DE ACESSOS $$ <br>\n" + " <br> \n" + " <span class=\"style2\">==========================================================</span><br>\n" + " </span><br>\n" + " <span class=\"style4\">VOC&Ecirc; POSSUI<span class=\"style9\">-</span> </span>\n" + " </h1>\n" + " <span class=\"style8\">\n" + " <?php\n" + " $caminho = \"contador.txt\";//nome do arquivo que vai guardar os visitantes\n" + " $arquivo = fopen($caminho, \"r\");//abre o arquivo\n" + " $total = fgets($arquivo,1024); //pega o numero de visitas\n" + " fclose($arquivo);//fecha o arquivo\n" + " $x = $total;\n" + " echo \"\" . $x;//mostra na tela o numero de visitantes\n" + "?>\n" + " </span> <span class=\"style4\"> CLIQUES.</span> <br>\n" + " <br>\n" + " <br>\n" + " <br>\n" + " <span class=\"style4\"><strong>OBS:</strong> A P&Aacute;GINA FICA ATUALIZANDO AUTOMATICAMENTE EM 60 SEGUNDOS. </span></p>\n" + " <table width=\"568\" border=\"0\">\n" + " <tr>\n" + " <td bgcolor=\"#000000\"><div align=\"center\"><span class=\"style12\">CONTADOR SPAM<span class=\"style11\"></span></span></div></td>\n" + " </tr>\n" + " </table>\n" + " <p><br>\n" + " </p>\n" + " <meta http-equiv='Refresh' content='60'; URL='contador.php'>\n" + "</center>\n" + "</body>\n" + "</head>\n" + "</html>"; final Pattern pattern = Pattern.compile(regex, Pattern.CASE_INSENSITIVE | 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