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 = "^\\s+\\\"#\\{prefix\\}\\.(.+)\\\":"; final String string = "\"use strict\"\n\n" + "define ->\n\n" + " launchOptions = (prefix) ->\n" + " options =\n" + " \"#{prefix}.businessCredits.businessBudgetFacility\": functionDetails: functionId : \"be.kbc.businessCredits.businessBudgetFacility\", mode: \"create\"\n" + " \"#{prefix}.businessCredits.taxPrepaymentPlan\": functionDetails: functionId : \"be.kbc.businessCredits.taxPrepaymentPlan\", mode: \"create\"\n" + " \"#{prefix}.credits.privateCreditCardRequest.update\": functionDetails: functionId : \"be.kbc.credits.privateCreditCardRequest\", mode: \"update\"\n" + " \"#{prefix}.credits.homeAtOnce\": functionDetails: functionId : \"be.kbc.credits.homeAtOnce\", mode: \"createRequest\"\n" + " \"#{prefix}.credits.homeAtOnce.detailRequest\": functionDetails: functionId : \"be.kbc.credits.homeAtOnce\", mode: \"detailRequest\"\n" + " \"#{prefix}.credits.homeAtOnce.editRequest\": functionDetails: functionId : \"be.kbc.credits.homeAtOnce\", mode: \"editRequest\"\n" + " \"#{prefix}.credits.homeAtOnce.updateRequest\": functionDetails: functionId : \"be.kbc.credits.homeAtOnce\", mode: \"updateRequest\"\n" + " \"#{prefix}.credits.budgetfacilitylight\": functionDetails: functionId : \"be.kbc.credits.budgetFacilityLight\", mode: \"create\"\n" + " \"#{prefix}.credits.loaRequest\": functionDetails: functionId : \"be.kbc.credits.loaRequest\", mode: \"create\"\n" + " \"#{prefix}.credits.loaRequest.update\": functionDetails: functionId : \"be.kbc.credits.loaRequest\", mode: \"update\"\n" + " \"#{prefix}.doccle.doccleAccount\": functionDetails: functionId : \"be.kbc.doccle.doccleAccount\", mode: \"create\"\n" + " \"#{prefix}.esigning.esigning\": functionDetails: functionId : \"be.kbc.esigning.esigning\", mode: \"create\"\n" + " \"#{prefix}.esigning.esigning.createBundle\": functionDetails: functionId : \"be.kbc.esigning.esigning\", mode: \"createBundle\"\n" + " \"#{prefix}.home.dinoHomeInsurance\": functionDetails: functionId : \"be.kbc.home.dinoHomeInsurance\", mode: \"create\"\n" + " \"#{prefix}.home.energyRenovationAdvice\": functionDetails: functionId : \"be.kbc.home.era\", mode: \"create\"\n" + " \"#{prefix}.insurances.smallProducts\": functionDetails: functionId : \"be.kbc.insurances.smallProducts\", mode: \"create\"\n" + " \"#{prefix}.insurances.smallproducts.external\": functionDetails: functionId : \"be.kbc.insurances.smallProducts\", mode: \"create\"\n" + " \"#{prefix}.insurances.insurancesUpsell\": functionDetails: functionId : \"be.kbc.insurances.insurancesUpsell\", mode: \"create\"\n" + " \"#{prefix}.investments.buycooperativeshares\": functionDetails: functionId : \"be.kbc.investments.buyCooperativeShares\", mode: \"create\"\n" + " \"#{prefix}.savings.acceptSavingsAccount\": functionDetails: functionId : \"be.kbc.savings.acceptSavingsAccount\", mode: \"create\"\n" + " \"#{prefix}.savings.manageAccountInsurance\": functionDetails: functionId : \"be.kbc.savings.manageAccountInsurance\", mode: \"create\"\n" + " \"#{prefix}.savings.manageAccountInsurance.delete\": functionDetails: functionId : \"be.kbc.savings.manageAccountInsurance\", mode: \"delete\"\n" + " \"#{prefix}.savings.openSavingsAccount\": functionDetails: functionId : \"be.kbc.savings.openSavingsAccount\", mode: \"create\"\n" + " \"#{prefix}.savings.settleSavingsAccount\": functionDetails: functionId : \"be.kbc.savings.settleSavingsAccount\", mode: \"create\"\n" + " \"#{prefix}.payments.businessAccountRequest\": functionDetails: functionId : \"be.kbc.payments.businessAccountRequest\", mode: \"create\"\n" + " \"#{prefix}.payments.cardPhoto\": functionDetails: functionId : \"be.kbc.payments.cardPhoto\", mode: \"create\"\n" + " \"#{prefix}.payments.preaccountrequest\": functionDetails: functionId : \"be.kbc.payments.preAccountRequest\", mode: \"create\"\n" + " \"#{prefix}.payments.privateAccountRequest\": functionDetails: functionId : \"be.kbc.payments.privateAccountRequest\", mode: \"create\"\n" + " \"#{prefix}.payments.businessCreditCardRequest\": functionDetails: functionId : \"be.kbc.payments.businessCreditCardRequest\", mode: \"create\"\n" + " \"#{prefix}.payments.preCardRequest\": functionDetails: functionId : \"be.kbc.payments.preCardRequest\", mode: \"create\"\n" + " \"#{prefix}.payments.preCardRequest.createReplacement\": functionDetails: functionId : \"be.kbc.payments.preCardRequest\", mode: \"createReplacement\"\n" + " \"#{prefix}.vehicle.dinoCarInsurance\": functionDetails: functionId : \"be.kbc.vehicle.dinoCarInsurance\", mode: \"create\"\n" + " \"#{prefix}.vehicle.privateLease\": functionDetails: functionId : \"be.kbc.vehicle.privateLease\", mode: \"create\"\n" + " \"#{prefix}.vehicle.privateLease.update\": functionDetails: functionId : \"be.kbc.vehicle.privateLease\", mode: \"update\"\n\n" + " # Note: the deeplinks below are for local development testing only, the won't be available in the pillars\n" + " # coffeelint: disable=no_backticks\n" + " `//>>includeStart(\"local\", pragmas.local)`\n" + " options[\"#{prefix}.credits.genericRequest\"] = functionDetails: functionId : \"be.kbc.credits.genericRequest\", mode: \"create\"\n" + " options[\"#{prefix}.credits.genericRequest.continue\"] = functionDetails: functionId : \"be.kbc.credits.genericRequest\", mode: \"continue\"\n" + " `//>>includeEnd(\"local\")`\n\n" + " return options\n\n" + " return launchOptions\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