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"
"
gmi

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 = "(cash\\sflows.*activities$|net.*cash.*and cash equivalents?)"; final String string = "CASH FLOWS FROM/(FOR) OPERATING ACTIVITIES\n" + "Profit before tax 75,615,413 46,147,364 17,519,528 13,008,793\n" + "Depreciation of property, plant and equipment 17,300,505 18,471,479 17,331 21,667\n" + "Interest expense 568,006 931,264 56,109 194,461\n" + "Allowance for impairment loss on property, plant and equipment 0 49,749 0 0\n" + "Unrealised (gain)/loss on foreign exchange -616,303 4,613,657 190,487 95,813\n" + "Allowance for impairment losses on amount owing by a subsidiary 0 0 1,242,999 270,000\n" + "Allowance for impairment losses on receivables 932,838 71,151 0 0\n" + "Bad debt written off 153,130 0 0 0\n" + "Inventories written off 0 137,087 0 0\n" + "Gain on disposal of an associate -672,207 0 0 0\n" + "Property, plant and equipment written off 10,678 506,875 0 0\n" + "Share of results in an associate -78,115 51,126 0 0\n" + "Interest income -917,220 -844,780 -549,987 -514,753\n" + "Gain on disposal of property, plant and equipment -164,099 -11,181 0 0\n" + "Writeback of allowance for impairment losses on trade receivables Dividend -10,000 -60,137 0 0\n" + "income from subsidiaries 0 0 -23,527,968 -17,028,204\n" + "Inventories -379,713 -2,955,410 0 0\n" + "Trade receivables -16,590,199 2,180,666 0 0\n" + "Other receivables and prepaid expenses -1,492,450 -424,370 -27,867 13,997\n" + "Amount owing by an associate 1,330,780 1,698 0 0\n" + "Trade payables -826,277 -1,354,959 0 0\n" + "Other payables and accrued expenses 3,376,361 9,419,139 1,190,933 956,353\n" + "Cash Generated From/(For) Operations 77,541,128 76,930,418 -3,888,435 -2,981,873\n" + "Taxes paid -14,218,858 -7,901,643 0 0\n" + "CASH FLOWS (FOR)/FROM INVESTING ACTIVITIES\n" + "Repayment from subsidiaries 0 0 1,514,464 9,000,836\n" + "Purchase of property, plant and equipment -7,492,297 -20,152,154 -3,689 -830\n" + "Dividend received from subsidiaries 0 0 21,039,335 14,800,304\n" + "Additional investment/acquisition of subsidiaries (Note 11) -7,133,082 -13,273,927 -7,133,082 -13,273,927\n" + "Proceeds from disposal of an associate 2,496,557 0 0 0\n" + "Proceeds from disposal of property, plant and equipment 1,077,256 138,530 0 0\n" + "Withdrawal of short-term investments 0 2,197,876 0 0\n" + "Net withdrawal/(placement) of fixed deposits with licensed banks 2,992,578 -1,833,200 1,104,683 -31,986\n" + "Interest received 917,220 844,780 549,987 514,753\n" + "CASH FLOWS FOR FINANCING ACTIVITIES\n" + "Decrease in amount owing to subsidiaries (Note 29(a)) 0 0 591,745 -5,754,789\n" + "Repayment of term loans (Note 29(a)) -16,712,117 -7,883,738 -2,037,933 -2,090,577\n" + "Interest paid -568,006 -931,264 -56,109 -194,461\n" + "Dividend paid by the Company (Note 26) -7,335,779 -5,239,843 -7,335,779 -5,239,843\n" + "Dividend paid by a subsidiary to non- controlling interests -2,626,027 -1,984,852 0 0\n" + "Drawdown of term loans (Note 29(a)) 0 7,901,920 0 0\n" + "Payment of hire purchase payables (Note 29(a)) -544,511 -251,063 0 0\n" + "NET INCREASE/(DECREASE) IN CASH AND CASH EQUIVALENTS 28,394,062 28,561,840 4,345,187 -5,252,393\n" + "Effect of exchange rate changes 293,086 -6,376,820 8,004 -374,697\n" + "CASH AND CASH EQUIVALENTS AT BEGINNING OF YEAR 120,252,919 98,067,899 9,757,017 15,384,107\n" + "CASH AND CASH EQUIVALENTS AT END OF YEAR (Note 29(b)) 148,940,067 120,252,919 14,110,208 9,757,017"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE | Pattern.CASE_INSENSITIVE); 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