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

/
/
gs

Test String

Substitution

Processing...

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+\\.){0,}([^A-Za-zА-Яа-я_])h([^A-Za-zА-Яа-я_]))(?:\\sAS \\[[A-Za-zА-Яа-я_]+\\]){0,}"; final String string = "SELECT `L`, \n" + "`r_e`, \n" + "T1.[r_w], \n" + "`Soi`, \n" + "`Sor`, \n" + "`Swc`, \n" + "`i_k_2`, \n" + "`mu_w`, \n" + "`mu_o`, `Газоконденсатный_фактор` AS [Газоконденсатный_фактор], `Газосодержание_нефти` AS [Газосодержание_нефти], \n" + "`Геологические_запасы_конденсата`, \n" + "`Геологические_запасы_нефти`, \n" + "`Геологические_запасы_свободного_газа`, \n" + "`D`, \n" + "`Извлекаемые_запасы_конденсата`, \n" + "`Извлекаемые_запасы_нефти_новых_скважин`, \n" + "`Извлекаемые_запасы_нефти`, \n" + "`КИН`, \n" + "`Количество_буровых`, \n" + "`Количество_скважин`, \n" + "`FracCount`, \n" + "`Fw`, \n" + "`F`, \n" + "`Коэффициент_компенсации`, \n" + "`phi`, \n" + "`Ef`, \n" + "`Объемный_коэффициент_воды`, \n" + "`Bo`, \n" + "`Период_строительства_скважины`, \n" + "`Плотность_воды`, \n" + "`ro_o`, \n" + "`Плотность_сетки_скважин`, \n" + "`Площадь_объекта`, \n" + "`k_h`, \n" + "`k_f`, \n" + "T1.`Pwf`, \n" + "`Psat`, \n" + "`c_w`, \n" + "`c_o`, \n" + "`c_r`, \n" + "`S`, \n" + "`Соотношение__доб_нагн__0___беск`, \n" + "`Стартовая_приемистость`, \n" + "`Стартовый_дебит_жидкости`, \n" + "`Стартовый_дебит_нефти`, \n" + "`m1`, \n" + "`m2`, \n" + "`Стоимость_скв__ГС+ГРП`, \n" + "`Стоимость_скв__ГС+МГРП`, \n" + "`Стоимость_скв__ГС`, \n" + "`Стоимость_скв__ННС+ГРП`, \n" + "`Стоимость`, \n" + "`Pi`, \n" + "`t_p`, \n" + "`Тип_заканчивания_доб_скв`, \n" + "`Тип_заканчивания_нагн__скв`, \n" + "`wf`, \n" + "T1.[h] FROM [DeleteMe5$A1:DM253]\n\n\n"; final String subst = "$1 Max($2) AS [Year]"; final Pattern pattern = Pattern.compile(regex, Pattern.DOTALL); final Matcher matcher = pattern.matcher(string); // The substituted value will be contained in the result variable final String result = matcher.replaceAll(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