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

/
/

Test String

Substitution

Processing...

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 = "(\\/\\/ \\[\\'administrator_start\\'\\])(.|\\n)*(\\/\\/ \\[\\'administrator_end\\'\\])"; final String string = " // ['administrator_start']\n" + " if ($_SESSION[\"user_group_short\"] == \"administrator\" && $_SESSION['active'] == 1) {\n" + "//\n" + "//\n" + "//Группа administrator\n" + "//\n" + "//\n" + " ?>\n" + " <div>\n" + " Администратор\n" + " </div>\n" + " <div id=\"databoard\">\n" + " <?php\n\n" + " function showTree($folder) {\n" + " /* Получаем полный список файлов и каталогов внутри $folder */\n" + " $files = scandir($folder);\n" + " foreach ($files as $file) {\n" + " /* Отбрасываем текущий и родительский каталог */\n" + " if (($file == '.') || ($file == '..')) {\n" + " continue;\n" + " }\n" + " $f0 = $folder . '/' . $file; //Получаем полный путь к файлу\n" + " /* Если это директория */\n" + " if (is_dir($f0)) {\n" + " /* Выводим, делая заданный отступ, название директории */\n" + " echo \"<p>\" . translate(iconv(mb_detect_encoding($file, mb_detect_order(), true), \"UTF-8\", $file)) . \"</p>\";\n" + " /* С помощью рекурсии выводим содержимое полученной директории */\n" + " showTree($f0);\n" + " } else {\n" + " /* Если это файл, то просто выводим название файла */\n" + " $name_page = explode(\".\", iconv(mb_detect_encoding($file, mb_detect_order(), true), \"UTF-8\", $file));\n" + " echo \"<a style='text-decoration: none;' href='\" . iconv(mb_detect_encoding($f0, mb_detect_order(), true), \"UTF-8\", $f0) . \"'>\" . translate($name_page[0]) . \"</a> \";\n" + " }\n" + " }\n" + " }\n\n" + " showTree(\"../pages/\" . $_SESSION['user_group_short']);\n" + " ?>\n" + " </div>\n" + " <?php\n" + " }\n" + "// ['administrator_end']\n" + "// ['insert_body']"; final String subst = ""; final Pattern pattern = Pattern.compile(regex); final Matcher matcher = pattern.matcher(string); // The substituted value will be contained in the result variable final String result = matcher.replaceFirst(subst); System.out.println("Substitution result: " + result); } }

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