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
Processing...

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 = "(.*?(cardNumber|card.number|number|cvc|cvv|cardVerificationCode|card_Verification_Code|cardVerificationValue|card_Verification_Value|expireMonth|expireYear|x-api-key|apiKey)[\\\\\\\\\\\"]*:[ \\\\[\\n\\\\\\\\\\\"\\\\]]*)[a-zA-Z0-9$&+,:;=?@#|\\'<>.^*()%!-]+(.*?)"; final String string = "{\"cardNumber\": \"34be18a5-f710-45ba-9b4d-0c13c9b07c7e\", \"http_method\": \"POST\", \"url\": \"https://api.qabakuun.cloud/ratedockAPI/RDK259/booking\", \"headers\": {\"User-Agent\": \"python-requests/2.28.1\", \"Accept-Encoding\": \"gzip, deflate\", \"Accept\": \"application/json\", \"Connection\": \"keep-alive\", \"Content-Type\": \"application/json\", \"Content-Length\": \"1791\"}, \"body\": {\"username\": \"rhcp@secretescapes.com\", \"password\": \"BbiqzYuP\", \"partnerId\": \"RDK259\", \"partnerName\": \"SecretEscapes\", \"action\": \"getBooking\", \"hotelReservation\": [{\"hotelCode\": \"TESTRATEDOCKHOTEL\", \"hotelName\": \"Test Ratedock Hotel\", \"resStatus\": \"New\", \"checkIn\": \"2022-10-10\", \"checkOut\": \"2022-10-12\", \"paymentMethod\": \"BANK\", \"rateType\": \"BAR\", \"currencyCode\": \"GBP\", \"totalAdult\": \"1\", \"totalChild\": \"0\", \"child_ages\": [], \"totalBaby\": \"0\", \"baby_ages\": [], \"roomStays\": [{\"roomTypeId\": \"TESTRATEDOCKROOMTYPE\", \"roomName\": \"Test Ratedock Room Type\", \"roomType\": \"Daily Room\", \"numberOfUnits\": \"1\", \"adultCount\": \"1\", \"childCount\": \"0\", \"child_ages\": [], \"babyCount\": \"0\", \"commission\": \"0.00\", \"roomIndex\": \"1\", \"ResGuestRPH\": \"1\", \"bookingPerDayPrices\": [{\"dateYmd\": \"2022-10-10\", \"price\": \"184.90\", \"ratePlanId\": \"TESTRATEDOCKRATEPLAN\", \"cancelPolicy\": \"\"}, {\"dateYmd\": \"2022-10-11\", \"price\": \"159.60\", \"ratePlanId\": \"TESTRATEDOCKRATEPLAN\", \"cancelPolicy\": \"\"}], \"total\": {\"amountAfterTaxes\": \"344.50\", \"amountBeforeTaxes\": \"344.50\"}, \"roomIncServices\": []}], \"guestDetails\": [{\"ResGuestRPH\": \"1\", \"firstName\": \"(redacted)\", \"lastName\": \"(redacted)\", \"middleName\": \"\", \"email\": \"test+uk@secretescapes.com\", \"phone\": \"123123123\", \"address\": \"\", \"country\": \"\"}], \"Comment\": {\"Text\": \"\"}, \"paymentCard\": {\"cardHolderName\": \"\", \"cardType\": \"\", \"cardCategory\": \"\", \"cardNumber\": \"\", \"ExpiryMonth\": \"\", \"ExpiryYear\": \"\", \"StartDayMonth\": \"\", \"StartDayYear\": \"\", \"IssueNum\": \"\", \"seriesCode\": \"\", \"vccCurrencyCode\": \"\", \"vccBalance\": \"\", \"vccDeactivationDate\": \"\", \"vccActivationDate\": \"\"}, \"totalCharge\": [{\"taxDetails\": {\"typeTax\": \"\", \"includes\": \"\", \"taxPrice\": \"\", \"taxDetails\": \"\"}, \"priceDetails\": [{\"rateType\": \"BAR\", \"amountAfterTaxes\": \"344.50\", \"amountBeforeTaxes\": \"344.50\"}]}]}]}}"; final String subst = "$1***$2"; final Pattern pattern = Pattern.compile(regex); final Matcher matcher = pattern.matcher(string); // The substituted value will be contained in the result variable final String result = matcher.replaceFirst(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