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 = "(Descrição:.{8})"; final String string = "\n" + " Pagamento Eletrônico de Tributos/Contas de Consumo Bradesco \n" + " Comprovante de Pagamento \n\n" + " GUIA NACIONAL DE RECOLHIMENTO ESTADUAL - GNRE \n\n" + " Código de Barras: 85840011134 1 62370278120 4 16110902000 4 02006081262 6 \n\n" + " Empresa / Órgão: SEFAZ RIO DE JANEIRO - GNRE/RJ \n\n" + " NOSSO NUMERO 02000020060812 \n\n" + " Descrição: GNRE Data de Vencimento: 09/11/2016 \n\n" + " Data do Pagamento: 09/11/2016 \n\n" + " Valor Principal: R$ 1.113.462,37 \n\n" + " Valor de Juros: R$ 0,00 \n\n" + " Valor de Multa: R$ 0,00 Valor do Pagamento: R$ 1.113.462,37 \n\n" + " Autenticação Bancária: 095465354 \n\n" + " Núm . de Controle: 60100608868888950348801055 \n\n" + " ICMS-ST INTEREST DE SP PARA RJ 102016 \n\n" + " A GNRE - Guia Nacional de Recolhimento de Tributos Estaduais acima foi efetuada através do PTRB - Pagamento Eletrônico de \n" + " Tributos, dentro das condições especificadas. O lançamento consta no extrato da conta junto à agência 313-1, data de pagamento \n" + " 09/11/2016. \n" + " N° do Documento: 04370837900012016110900158 \n" + " Alô Bradesco – SAC – 0800 704 8383 Deficiente Auditivo – 0800 722 0099, atendimento 24 horas, 7 dias por semana. Ouvidoria – 0800 \n" + " 727 9933, atendimento de 2ª a 6ª feira das 8h às 18h, exceto feriados \n\n" + " Banco Bradesco S/A \n\n\n"; final String subst = "$1"; 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