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

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 = "^(Depense|Recette)_Aller_\\d*_*(FEDER|RR974|POCT)_\\d{2}_\\d{4}_\\d{1,2}_\\d+C\\w*.xml$"; final String string = "Depense_Aller_4689.xml : flux PJ seul, bordereau déjà envoyé, à ne pas signer\n\n" + "Depense_Aller_4659_661C.xml : flux complet, à signer DAF\n\n" + "Depense_Aller_FEDER_01_2017_1_19C.xml\n\n" + "Depense_Aller_FEDER_01_2017_1_19C_Auto.xml\n" + "Depense_Aller_7864_FEDER_01_2017_2_19C_Auto.xml\n\n" + "Depense_Aller_4344_SMPRR_01_2017_2_34C_Auto.xml\n\n" + "Depense_Aller_4344_RR974_01_2017_6_566C_Auto.xml\n" + "Depense_Aller_4038_RR974_01_2017_473C_Auto.xml\n\n" + "Depense_Aller_3469_RR974_01_2017_271C_Auto.xml : flux complet paye, à signer RH\n\n" + "Depense_Aller_4271_FEDER_01_2016_5A_Auto.xml : flux en annulation, à ne pas signer\n\n" + "Depense_Aller_2649_RR974_01_2017_5C_Auto.xml : flux indemnités élus Région, à signer par ?\n\n" + "Depense_Aller_3222_RR974_01_2017_216C_Auto.xml : flux indemnités élus CESER, à signer par ?\n\n" + "Depense_Aller_3222_RR974_01_2017_219C_Auto.xml : flux indemnités élus CCEE, à signer par ?\n\n\n" + "Appgfi\\wwwGFTEST\\astre\\astromate\\pes\\recette :\n\n" + "Recette_Aller_4271_RR974_01_2017_6C_Auto.xml : flux recette, à signer DAF\n\n" + "Recette_Aller_4271_RR974_01_2016_21A_Auto.xml : flux recette en annulation, à ne pas signer\n"; 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.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