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

/
/
msu

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 = "(?=(?:\"\"\\s+?Controle\\s*Fiscal[\\w\\W]+?)?\"\"\\s+(?<NomeUc>[\\w\\W]+?)$(?:.*?)\"\"\\s+?(?<Cnpj>\\d{14})\\s*(?:.*?)(?<MesReferencia>\\d{2}\\/\\d{4})(?:.*?)(?<DtEmissao>\\d{2}\\/\\d{2}\\/\\d{4})(?:.*?)\\d{2}\\/\\d{2}\\/\\d{4}\\s+(?<NumFatura>\\d+)\\s+(?:.*?)(?<ExternalCode>\\d+-\\d+)\\s+(?:.*?)(?<DtVencimento>\\d{2}\\/\\d{2}\\/\\d{4})\\s+(?:.*?)(?<VlrTotalFatura>[0-9\\.]+,?\\d*)(?:.*?)Consta\\snesta\\sfatura\\s*R.\\s(?<VlrPisCofins>[0-9\\.]+,?\\d*)\\sreferentes\\sa\\s(?:.*?)(?<AliqPis>[0-9\\.]+,?\\d*)%\\sde\\sPIS\\se\\s(?:.*?)(?<AliqCofins>[0-9\\.]+,?\\d*)%\\sde\\sCOFINS(?:.*?)\\)\\s+\\d+\\s+(?:\\d+)?\\s+(?<VlrBaseIcms>[0-9\\.]+,?\\d*)(?:.*?)\"\"\\s+(?<AliqIcms>\\d+)\\s+(?:.*?)^(?<DContratadaFp>[0-9\\.]+,?\\d*)\\s+(?:.*?)[0-9\\.]+,?\\d*\\s+(?<VlrIcms>[0-9\\.]+,?\\d*)\\s+(?:.*?)\"\"\\s+(?<DataLeituraAtual>\\d{2}\\/\\d{2}\\/\\d{4})\\s+(?:.*?)(?<DataLeituraAnterior>\\d{2}\\/\\d{2}\\/\\d{4})\\s+(?:.*?)\"\"\\s+(?<LeituraAtualCFp>[0-9\\.]+,?\\d*)\\s+(?:.*?)(?<LeituraAnteriorCFp>[0-9\\.]+,?\\d*)\\s+(?:.*?)(?<ConstanteConsumoFp>[0-9\\.]+,?\\d*)\\s+(?:.*?)(?<CMedidoFp>[0-9\\.]+,?\\d*)\\s+(?:.*?)(?<LeituraAtualCP>[0-9\\.]+,?\\d*)\\s+(?:.*?)(?<LeituraAnteriorCP>[0-9\\.]+,?\\d*)\\s+(?:.*?)(?<ConstanteConsumoP>[0-9\\.]+,?\\d*)\\s+(?:.*?)(?<CMedidoP>[0-9\\.]+,?\\d*)(?:.*?))"; final String string = "\"\" Controle Fiscal: 0B3EADFCEE1EECF867DEBB24AB24C691\n" + "\"\" AGUAS DE NITEROI S/A \n" + "\"\" ROD BR 101 KM 30,5, S/N DISTRITO CONSELHEIRO \n" + "\"\" 02150336000166 0704097\n" + "\"\" 86 41570091 0108-8\n" + "\"\" FAZ NOVA GAIVOT 12/2019\n" + "\"\" CAMPOS DOS GOYTACAZES 20/12/2019\n" + "\"\" 28100-000 24/12/2019\n" + "4421 Segunda Via\n" + "7889020-9 16/01/2020 2.447,37\n" + "Cons Fat Ponta 814,00 kWh2,781802.264,38\n" + "Cons Fat F Ponta 8568,00 kWh 0,541594.640,34\n" + "Dem Fat F Ponta 73,00 kW31,790002.320,67\n" + "Ajuste -4.833,30\n" + "Iluminacao Publica 126,69\n" + "ENERGIA CONSUMIDA GD BAND VERDE 6.015,70\n" + "Cred Energia Injetada G. Distribuida -6.015,70 0,00\n" + "Devolucao ICMS -2.071,41\n" + "\"\" 0,00\n" + "VR ADIC BAND AMARELA DO MES ( R$ 347,52 ) \n" + "Consta nesta fatura R$ 533,22 referentes a 1,04% de PIS e 4,74% de COFINS \n" + "(Art. 10 Res. 298/2006-ANEEL e Leis N. 10.637/02 e 10.883/03) \n" + "33375978 9.225,39 \n" + "\"\" 30 \n" + "1.000,00 0,00 2.767,61 \n" + "Tipo de Faturamento: Normal \n" + "19/12/2019 19/11/2019 19/12/2019 19/11/2019\n" + "357,00 255,00 84,000 8568,00 3555,00 2586,00 0,840 814,00\n" + "63,00 41,00 3,360 73,00 46,00 30,00 3,360 53,00\n" + "1,00 1,00 84,000 0,00 0,00 0,00 0,840 0,00\n" + "219,00 140,00 0,840 66,36 137,00 89,00 0,840 40,32\n" + "\"\" 13,80 kV IGOR MACHADO\n" + "\"\" 20/01/2020\n" + "0 0 0 0 0 THS VERDE A4 C/DES15Telefone:2716-1634\n" + "0 0 0 0 14,49 kV\n" + "0 0 E-mail:igor.santos@enel.com10/2019 Servico Publico\n" + "\"\" 12,83 kV 0,00%\n" + "0 0 \n" + "Banco Itaú SA 341-7 34191.09008 30346.832931 83707.520009 1 81360000244737 \n" + "PAGÁVEL PREFERENCIALMENTE NO ITAÚ Contra-apresentação\n" + "AMPLA Energia e Serviços S.A. 2938/37075-2\n" + "20/12/2019 4421 DP N 175/00303468-3\n" + "\"\" 175 2.447,37\n" + "Pagamentos efetuados após o dia 16/01/2020, incorrerão encargos financeiros de mora. \n" + "Os encargos financeiros citados, serão cobrados em faturas posteriores. \n" + "Regime Especial - processo no E-04/142.091/97 \n" + "AGUAS DE NITEROI S/A \n" + "ROD BR 101 KM 30,5, S/N DISTRITO CONSELHEIRO \n" + "\"\" CONTA PAGA \n"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE | Pattern.DOTALL | Pattern.UNICODE_CASE); final Matcher matcher = pattern.matcher(string); if (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