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

Generated Code

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "\\/\\*[\\s\\S]*?\\*\\/"; final String string = "var ExecutionScript = (function () {\n" + " function ExecutionScript() {\n" + " }\n" + " ExecutionScript.prototype.RemoveSchemes = function (e) {\n" + " var _this = this;\n" + " debugger;\n" + " return new Promise(function (resolve, reject) { return __awaiter(_this, void 0, void 0, function () {\n" + " var selectedRole, currentSchemes, schemesToRemove, tempSchemes, filteredSchemes, _loop_1, newSchemes, _i, schemesToRemove_1, selectedScheme, _a, _b, scheme_1, newSchemes, _c, newSchemes_1, s;\n" + " return __generator(this, function (_d) {\n" + " switch (_d.label) {\n" + " case 0://test\n" + " selectedRole = e.data.Role_Variable.currentItem.Role.currentItem;\n" + " currentSchemes = selectedRole.Scheme.value;\n" + " schemesToRemove = e.plugins.Schemes_From_Data_Grid.SelectedItems;\n" + " tempSchemes = e.data.Temp_Role_Variable.currentItem.Scheme;\n" + " _loop_1 = function (selectedScheme) {\n" + " var _i, filteredSchemes_1, scheme, _a, newSchemes_2, s;\n" + " return __generator(this, function (_b) {\n" + " switch (_b.label) {\n" + " case 0:\n" + " filteredSchemes = currentSchemes.filter(function (scheme) { return scheme.ID !== selectedScheme.ID; });\n" + " _i = 0, filteredSchemes_1 = filteredSchemes;\n" + " _b.label = 1;/*\n" + " * testing multline comment\n" + " \n" + " */case 1:\n" + " if (!(_i < filteredSchemes_1.length)) return [3 /*break*/, 4];\n" + " scheme = filteredSchemes_1[_i];/*\n" + " * testing multline comment\n" + " */\n" + " return [4 /*yield*/, tempSchemes.create(1, false, e.data.Temp_Role_Variable.currentItem)];\n" + " case 2:\n\n" + " /*\n\n" + " * testing multline comment\n" + " */\n" + " newSchemes = _b.sent();\n" + " for (_a = 0, newSchemes_2 = newSchemes; _a < newSchemes_2.length; _a++) {\n" + " s = newSchemes_2[_a];\n" + " s.Active = scheme.Active;\n" + " s.Description = scheme.Description;\n" + " s.DisplayName = scheme.DisplayName;\n" + " s.Name = scheme.Name;\n" + " s.Role = scheme.Role;\n" + " s.SchemeId = scheme.SchemeId;\n" + " }\n" + " debugger;\n" + " tempSchemes.addItems(newSchemes);\n" + " _b.label = 3;\n" + " case 3://\n" + " _i++;\n" + " return [3 /*break*/, 1];\n" + " case 4: return [2 /*return*/];\n" + " }\n" + " });\n" + " };//\n" + " _i = 0, schemesToRemove_1 = schemesToRemove;\n" + " _d.label = 1;\n" + " case 1:\n" + " if (!(_i < schemesToRemove_1.length)) return [3 /*break*/, 4];\n" + " selectedScheme = schemesToRemove_1[_i];\n" + " return [5 /*yield**/, _loop_1(selectedScheme)];\n" + " case 2:\n" + " _d.sent();\n" + " _d.label = 3;\n" + " case 3:\n" + " _i++;\n" + " return [3 /*break*/, 1];\n" + " case 4:\n" + " // }\n" + " selectedRole.Scheme.clear();\n" + " _a = 0, _b = tempSchemes.value;\n" + " _d.label = 5;\n" + " case 5:\n" + " if (!(_a < _b.length)) return [3 /*break*/, 8];\n" + " scheme_1 = _b[_a];\n" + " return [4 /*yield*/, selectedRole.Scheme.create(1, false, e.data.Role_Variable.currentItem)];\n" + " case 6:\n" + " newSchemes = _d.sent();\n" + " for (_c = 0, newSchemes_1 = newSchemes; _c < newSchemes_1.length; _c++) {\n" + " s = newSchemes_1[_c];\n" + " s.Active = scheme_1.Active;\n" + " s.Description = scheme_1.Description;\n" + " s.DisplayName = scheme_1.DisplayName;\n" + " s.Name = scheme_1.Name;\n" + " s.Role = scheme_1.Role;\n" + " s.SchemeId = scheme_1.SchemeId;\n" + " }\n" + " selectedRole.Scheme.addItems(newSchemes);\n" + " _d.label = 7;\n" + " case 7:\n" + " _a++;\n" + " return [3 /*break*/, 5];\n" + " case 8:\n" + " e.data.Role_Variable.currentItem;\n" + " selectedRole.ConfiguredStatus = 'Complete';\n" + " resolve();\n" + " return [2 /*return*/];\n" + " }\n" + " });\n" + " }); });\n" + " };\n" + " ExecutionScript.prototype.S_On_Previous = function (e) {\n" + " e.data.currentUser.currentItem.Role.clear();\n" + " };\n" + " return ExecutionScript;\n" + "}());"; 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