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 = "^(.+)$"; final String string = "03/01/2022,7−ELEVEN − TTSH LEV SINGAPORE SG,,SGD 1.10\n" + "03/01/2022,7−ELEVEN − TTSH LEV SINGAPORE SG,,SGD 2.00\n" + "03/01/2022,HEAVENLYWANG@HWMW SINGAPORE SG,,SGD 10.60\n" + "03/01/2022,DON DON DONKI SINGAPORE SG,,SGD 11.60\n" + "03/01/2022,LIFELINE CORPORATIO SINGAPORE SG,,SGD 106.00\n" + "04/01/2022,ESSO−CHEERS BY FP SINGAPORE SG,,SGD 2.50\n" + "04/01/2022,MCDONALD'S (QSC) SINGAPORE SG,,SGD 7.10\n" + "04/01/2022,SHELL PAYA LEBAR MA SINGAPORE SG,,SGD 17.35\n" + "03/01/2022,PAYMENT − THANK YOU 8,978.47CR\n" + "04/01/2022,SINGPOST − SAM KIOS SINGAPORE SG,,SGD 2.40\n" + "04/01/2022,Artisan Boulangerie Singapore SG,,SGD 9.94\n" + "05/01/2022,W S GO & ASSOCIATES SINGAPORE SG,,SGD 374.50\n" + "06/01/2022,ECCELLENTE MARINA SINGAPORE SG,,SGD 1.90\n" + "06/01/2022,COLD STORAGE−GREAT SINGAPORE SG,,SGD 16.10\n" + "06/01/2022,STARBUCKS@GREAT WLD SINGAPORE SG,,SGD 18.00\n" + "06/01/2022,STARBUCKS@GREAT WLD SINGAPORE SG,,SGD 18.00\n" + "06/01/2022,HIRAKI SINGAPORE SG,,SGD 30.48\n" + "06/01/2022,SINGAPORE NATIONAL SINGAPORE SG,,SGD 154.08\n" + "07/01/2022,KRAFTWICH @ PLSQ SINGAPORE SG,,SGD 20.30\n" + "07/01/2022,KIM CHOO HOLDINGS P SINGAPORE SG,,SGD 33.00\n" + "08/01/2022,STARBUCKS@WIKIE EDG SINGAPORE SG,,SGD 18.00\n" + "10/01/2022,ECCELLENTE MARINA SINGAPORE SG,,SGD 1.90\n" + "10/01/2022,MCDONALD'S (PSA) SINGAPORE SG,,SGD 17.80\n" + "11/01/2022,BRAWN AND BRAINS SINGAPORE SG,,SGD 31.90\n" + "11/01/2022,12 Jan A POKE THEORY−TRIPL SINGAPORE SG,,SGD 16.50"; final String subst = "$1 DR"; 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