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

r"
"
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 = "(^[A-Z]).*\\n[A-Za-z 1-9]*\\s(\\d)*\\s"; final String string = "Frontken Corporation Berhad (651020-T) 85 \n" + "ANNUAL REPORT 2018 \n" + " \n" + "Notes To The Financial Statements \n" + "(cont’d) \n" + " \n" + " \n" + "9. EARNINGS PER SHARE \n" + " \n" + "Basic earnings per share is calculated by dividing profit after taxation attributable to owners of the Company by the weighted \n" + "average number of ordinary shares in issue during the financial year. \n" + " \n" + " The Group \n" + "2018 2017 \n" + "Profit after taxation attributable to owners of the Company (RM) 52,256,898 29,857,681 \n" + "Number of shares in issue as of 1 January 1,053,435,130 1,053,435,130 \n" + "Effects of: \n" + "Treasury shares acquired (5,466,600) (5,466,600 ) \n" + "Weighted average number of ordinary shares for basic earnings \n" + "per share computation as of 31 December 1,047,968,530 1,047,968,530 \n" + " \n" + " \n" + "Basic earnings per ordinary share attributable \n" + "to equity holders of the Company (sen) 4.99 2.85 \n" + "The Group has not issued any dilutive potential ordinary shares and hence, the diluted earnings per share is equal to the basic \n" + "earnings per share. \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