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

/
/
gi

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 = "[\\r\\n]+\\s*\\/\\/.*TODO:+.*"; final String string = "angular\n" + " .module('mdKeyboard', ['material.components.bottomSheet'])\n" + " .directive('mdKeyboard', MdKeyboardDirective)\n" + " .provider('$mdKeyboard', MdKeyboardProvider);\n\n\n" + "function MdKeyboardDirective($mdKeyboard, $mdBottomSheet, $timeout, $injector, $log) {\n" + " return {\n" + " restrict: 'A',\n" + " require: '?ngModel',\n" + " scope: {\n" + " clickOutsideToClose: '=',\n" + " preserveScope: '=',\n" + " showInMobile: '='\n" + " },\n" + " link: function (scope, element, attrs, ngModelCtrl) {\n" + " if (!ngModelCtrl) {\n" + " return;\n" + " }\n\n" + " var bottomSheet;\n\n" + " // Don't show virtual keyboard in mobile devices (default)\n" + " //TODO: test detection and reimplement if neccessary\n" + " //TODO: dissolve dependency to UAParser if possible / use angular or material utils\n" + " if ($injector.has('UAParser')) {\n" + " var UAParser = $injector.get('UAParser');\n" + " var results = new UAParser().getResult();\n" + " var isMobile = results.device.type === 'mobile' || results.device.type === 'tablet';\n" + " isMobile = isMobile || (results.os && (results.os.name === 'Android'));\n" + " isMobile = isMobile || (results.os && (results.os.name === 'iOS'));\n" + " isMobile = isMobile || (results.os && (results.os.name === 'Windows Phone'));\n" + " isMobile = isMobile || (results.os && (results.os.name === 'Windows Mobile'));\n" + " if (isMobile && attrs.showInMobile !== true) {\n" + " return;\n" + " }\n" + " }\n\n" + " /*\n" + " ngVirtualKeyboardService.attach(elements[0], scope.config, function() {\n" + " $timeout(function() {\n" + " ngModelCtrl.$setViewValue(elements[0].value);\n" + " });\n" + " });\n" + " */\n\n" + " $log.debug(attrs);\n" + " element\n" + " .bind('focus', showKeyboard)\n" + " .bind('blur', hideKeyboard);\n\n" + " function showKeyboard() {\n" + " $log.info('showKeyboard');\n" + " bottomSheet = $mdBottomSheet\n" + " .show({\n" + " template: '<md-bottom-sheet class=\"md-grid\" layout=\"column\" ng-cloak>{{keyboard}}</md-bottom-sheet>',\n" + " controller: KeyboardController,\n" + " clickOutsideToClose: attrs.clickOutsideToClose || false,\n" + " preserveScope: attrs.preserveScope || true\n" + " })\n" + " .then(function () {\n\n" + " });\n" + " }\n\n" + " function hideKeyboard() {\n" + " $log.info('hideKeyboard');\n" + " if (bottomSheet) {\n" + " $mdBottomSheet.hide();\n" + " delete bottomSheet;\n" + " }\n" + " }\n\n" + " function KeyboardController($scope, $mdBottomSheet) {\n" + " $scope.keyboard = 'TEST';\n" + " }\n\n" + " // open bottomsheet with keyboard on focus TODO: and without backdrop\n" + " scope.keyboard = 'test';\n\n" + " // When navigation force destroys an interimElement, then\n" + " // listen and $destroy() that interim instance...\n" + " scope.$on('$destroy', function () {\n" + " $mdKeyboard.destroy();\n" + " });\n" + " }\n" + " };\n" + "}\n\n" + "function MdKeyboardProvider($$interimElementProvider) {\n" + " return $$interimElementProvider('$mdKeyboard')\n" + " .setDefaults({\n" + " options: keyboardDefaults\n" + " });\n\n" + " function keyboardDefaults() {\n" + " return {\n" + " themable: true,\n" + " layout: defaultLayout\n" + " };\n\n" + " function defaultLayout() {\n" + " // get default language\n" + " return 'en-us';\n" + " }\n" + " }\n" + "}\n"; final Pattern pattern = Pattern.compile(regex, Pattern.CASE_INSENSITIVE); 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