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

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 = "(?:[0-2])?[0-9]:[0-5][0-9](?::[0-5][0-9])?(?:(?:\\\\s)?[AP]M)?"; final String string = "Nos dois sistemas.\n\n" + "Em 22 de maio de 2018 10:23, Sistema Delta <sistemaerp@deltasi.com.br>\n" + "escreveu:\n\n" + "> ##- Não escreva abaixo desta linha -##\n" + ">\n" + "> *Comentário adicionado por FERNANDO TEIXEIRA BARROS em 22/05/2018 10:23*\n" + "> *Usuário:* FERNANDO TEIXEIRA BARROS* Data:* 22/05/2018 10:23:25\n" + ">\n" + "> *COMENTÁRIO:*\n" + "> Bom dia Mayla,\n" + "> Apenas sistema Montafarma?\n" + "> ------------------------------\n" + ">\n" + "> *ID Reporte: * #1468\n" + "> *Situação: * *ABERTO*\n" + "> *Módulo:* Produção\n" + "> *Tela:* ordem de pedido\n" + "> *Nome: * mayla.capana - MAYLA CAPANA\n" + "> *Emissão: * 22/05/2018 12:00:00\n" + "> *Fechamento: * -\n" + "> *Responsável: * DELTA SI\n" + "> *Prioridade: * Urgente\n" + "> *Tipo: * Ajuda\n" + ">\n" + "> *MENSAGEM: *\n" + "> Bom dia,\n" + ">\n" + "> Por favor liberar o meu acesso, Izac e Priscila, para a tela de Produção -\n" + "> Ordem de Pedido. (igual a tela que a Iza tem acesso).\n" + ">\n" + "> Aguardo retorno.\n" + ">\n" + "> Até,\n" + ">\n" + ">"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE); 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