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 = "(?<=[^0-9][^0-9]\\s)(?P<val>[1-9]|[1-2][0-9]|3[0-3])(?=\\s[^a-z\\s]+\\s[^a-z\\s]+\\s[^a-z\\s]+$)"; final String string = "Increase)/Decrease in inventories -6,999,009 3,784,581\n" + "Increase)/Decrease in receivables -7,393,450 3,842,984\n" + "Increase/(Decrease) in payables 5,821,857 -18,006,883\n" + "Grant received 0 625,255\n" + "Interest paid -565,584 -1,495,877\n" + "Tax paid -22,168 -21,694\n" + "The annexed NOTEs form an integral part of the financial statements.\n" + "36\n" + "Annual Report 2012\n" + "Pentamaster Corporation Berhad (5723070 ) www.pentamaster.com\n" + "CONSOLIDATED STATEMENT OF CASH FLOWS\n" + "FOR THE YEAR ENDED 31 DECEMBER 2012 (CONT'D)\n" + "2012 2011\n" + "RM RM\n" + "CFI\n" + "Dividend income 80,863 81,078\n" + "Interest received 67,568 316,523\n" + "Proceeds from disposal of property, plant and equipment/non current assets held for sale 27 28,000 48,298,000\n" + "Purchase of property, plant and equipment 27 -64,624 0\n" + "CFF\n" + "Short term borrowings obtained/(repaid) 6,367,671 -4,757,230\n" + "Net term loans repaid -3,382,414 -40,376,659\n" + "Net Cash Flow -838,456 -168,122\n" + "Cash and cash equivalents brought forward 5,939,258 6,147,628\n" + "FOREIGN CURRENCY EXCHANGE\n" + "DIFFERENCES ON OPENING BALANCE 35 -40,248\n" + "Cash and cash equivalents carried forward 5,100,837 5,939,258\n" + "RM RM\n" + "CFO\n" + "Loss)/Profit before taxation -2,083,184 2,145,073\n" + "Adjustments for :0\n" + "Amortisation of intangible assets 2,689,572 4,087,413\n" + "Bad debts written off 7,594 0\n" + "Deferred income released -1,854,722 -3,786,856\n" + "Depreciation 2,855,169 2,941,851"; 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