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

/
/
gm

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 = "(PA - REAL PARQUE(?s)(.*)mon\\n999(?#Limpa o cabeçalho do Slip))"; final String string = "PA - REAL PARQUE CIA BRASILEIRA DE DISTRIBUICAO AV. MAJOR SYLVIO DE M PADILHA, 13000 REAL PARQUE, SAO PAULO - SP\n" + "209 GIA) 29 78093 - ETTUATO Me 02:16\n" + "anom\n" + "CNPJ 47.508.411/0617-08|\n" + "IE 116.804.053.119 IM 0000.000.000.000\n" + "Extrato No. 105102 CUPOM FISCAL ELETRÔNICO - SAT\n" + "CPF/CNPJ do Consumidor: Razão Social/Hone:\n" + "# I COD DESC ! QTD I UN I VL UN R$ 1 (ULTR R$)* 1 VL ITEM R$\n" + "wa Sasadas\n" + "mon\n" + "999\n" + "001 00000004550280 ARROZ AG PRATO F IKG 1 UN X 3,69 (0,15) 3,69 002 00000000029995 PEITO SEARA kg 0,908 KG X 11,99 (1,77) 10,89 003 00000000029995 PEITO SEARA kg 0,866 KG X 8,99 (1,26) 7,79 004 00000001182380 QA GRA LGH BA QUI800 1 UN X 14.90 (0,83) desconto sobre item 005 00000001182380 QA GRA LGH BA QUI800 1 UN X 14,90 (1,67) 006 00000001184166 FILE CX SOB ATN NAT 1 UN X 15,99 (2,59) 15,99 007 00000001005372 TQ IOG DES AMO C/ALE 1 UN X 9,59 (1,07) 9,59 008 00000001005372 TQ IOG DES ANO C/ALE 1 UN X 9,59 (1.07) 9.59 009 00000000219631 MAMAO FORMOSA KG 2 KG X 6,99 (2,48) desconto sobre iten 010 00000001090888 CHUCHU 500G 1 UN X 3,69 (0.82) 011 00000001090208 ABOBRINHA ITALIA 400 1 UN X 4,49 (0,89) desconto sobre iten 012 00000000102056 QJ PARMESAO LA SEREN 0,228 KG X 49,90 (2,94) 013 00000000102056 QJ PARMESAO LA SEREN 0,230 KG X 49,90 (2,96) 014 00000006277901 ALFACE M R 150G 1 UN X 4,99 (1,11) 015 00000006277901 ALFACE M R 150G 1 UN X 4,99 (1,11) 4,99 016 00000000250399 BANANA NANICA GNEL K 1,245 KG X 4,99 (0,96)\n" + "6,21 desconto sobre iten\n" + "-1,87 | 017 00000000357593 TOMATE ITALIANO kg 1,590 KG X 6,59 (2,33)\n" + "10,48 018 00000001166247 QA NOZES S CASCA 140 1 UN X 19,99 (4,87)\n" + "19,99 019 00000004911166 QA LARANJA PERA 3KG 1 UN X 13,99 (2.33) 13,99 desconto sobre item\n" + "-3,50 Total bruto de itens\n" + "193,01 Total de descontos/acréscimos sobre item\n" + "-16,12 TOTAL R$\n" + "176,89 CARTAOON\n" + "176,89\n" + "4,99\n" + "Comete crime quen sonega\n" + "OBSERVACOES DO CONTRIBUINTE DataMov: 20190821 Loja: 1299 Terminal: 057 NCupom: 000149191 Valor aproximado dos tributos deste cupom R$\n" + "33.21 (conforme Lei Fed 12.741/2012)\n" + "3519 0847 5084 1106 1708 5900 0291 4731 0510 2996 1014\n"; final String subst = ""; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE); 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