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 = "\\b([a-zA-Z]*)(ne|eb|ar|(?<!nom)br|il|ay|yo|un|nio|ul|lio|go|sto|ep|mbr|ct|ubr|ov|ic|en|ero|fe(?!cha)|ma|ab|ju|jo|ja|jn|ag|se|oc|nov|dic)([a-zA-Z]*)[- \\/.,\\n|i]{1,3}(0[1-9]|[12][0-9]|3[01]|[1-9]|i|o[1-9zi]|i[1-9zo])[- \\/.,\\n|i]{1,3}[2z][0o]\\d{0,2}\\b"; final String string = "Feb zi /\n" + "zozo\n" + "10\n" + "12030\n" + "nombre\n" + "fecha\n" + "01 / 2020\n" + "yl-20-2.020\n" + "FECHA: 2020-06-04 08:57:29\n" + "FECHA: 12 106 120\n" + "GARAG\n" + "marzo\n" + "15/2000\n" + "mayo 15/20\n" + "jul 1/20\n" + "Junio 17/20\n" + "S:\n" + "BUN\n" + "Centro Médico\n" + "FECHA:\n" + "05 06 - 2020\n" + "Warta carolina onerrez\n" + "Nombre:\n" + "1/6/200\n" + "ONDY Soklo\n" + "Fecha:\n" + "nFECHA: 2020-06-04 08:57:29\n" + "FECHA: 2020-06-04 08:57:2\n" + "Bogotá, 08/jun./2020\n" + "FECHA 11/06/2020\n" + "nBOGOTAOC - 10/06/2020\n" + "1/6/200\n" + "ONDY Soklo\n" + "Fecha:\n" + "echa 24-unio 12020\n" + "Fecha:\n" + "17.06.2020\n" + "FECHA:\n" + "2020\n" + "24 Junio\n" + "Fecha: 12 - vw\n" + "FECHA\n" + "VUNIO 18\n" + "18/2010\n" + "Jula 2020\n" + "FECHA:\n" + "05 06 - 2020\n" + "10 /m/ 200\n" + "2020\n\n" + "FECHA\\nTo\\nol06\n" + "\\n18106 12020\\n\n" + "204\\nFecha:\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