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

/
/
g

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 = "(?ms)<PNR>([\\w]+)<\\/PNR>\n"; final String string = "<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"yes\"?>\n" + "<EGE_Booking>\n" + " <TripID>1004-3637-360</TripID>\n" + " <RecordLocator>1004-3637-360</RecordLocator>\n" + " <Travelers>\n" + " <Traveler>\n" + " <PerCode>13593199</PerCode>\n" + " <FirstName>Claude</FirstName>\n" + " <LastName>Christensson</LastName>\n" + " <ContactDetails>\n" + " <Email>claude.christensson@wirelesscar.com</Email>\n" + " <MobilePhone>46765537005</MobilePhone>\n" + " </ContactDetails>\n" + " <TravellerCostCenter>\n" + " <CostCenter Code=\"CC3\">\n" + " <Label>Employee ID</Label>\n" + " <Value>56524</Value>\n" + " </CostCenter>\n" + " <CostCenter Code=\"CC4\">\n" + " <Label>Global Department code</Label>\n" + " <Value>DI43400</Value>\n" + " </CostCenter>\n" + " </TravellerCostCenter>\n" + " </Traveler>\n" + " </Travelers>\n" + " <Segments>\n" + " <HotelSegment>\n" + " <HOTEL>\n" + " <TripItemID>5a7dc8f971ac0163f7563e7e</TripItemID>\n" + " <PNR>ABC1DS</PNR>\n" + " <Status>V</Status>\n" + " <CheckInDate>2018-02-13</CheckInDate>\n" + " <CheckOutDate>2018-02-14</CheckOutDate>\n" + " <Vendor SupplierType=\"11281422\">Genting Hotel</Vendor>\n" + " <PropertyName>Genting Hotel</PropertyName>\n" + " <Location>\n" + " <Name>Pendigo Way, England, B40 1PU</Name>\n" + " <City>Birmingham</City>\n" + " <Country Code=\"GBR\">Storbritannien</Country>\n" + " </Location>\n" + " <ConfirmationCode>982674693</ConfirmationCode>\n" + " <Cost>\n" + " <Amount>751.08</Amount>\n" + " <Currency Code=\"SEK\">Swedish Krona</Currency>\n" + " </Cost>\n" + " <OutOfPolicyReasons/>\n" + " </HOTEL>\n" + " <HOTEL>\n" + " <TripItemID>5a7dc8f971ac0163f7563e7e</TripItemID>\n" + " <PNR>55545261643</PNR>\n" + " <Status>V</Status>\n" + " <CheckInDate>2018-02-13</CheckInDate>\n" + " <CheckOutDate>2018-02-14</CheckOutDate>\n" + " <Vendor SupplierType=\"11281422\">Genting Hotel</Vendor>\n" + " <PropertyName>Genting Hotel</PropertyName>\n" + " <Location>\n" + " <Name>Pendigo Way, England, B40 1PU</Name>\n" + " <City>Birmingham</City>\n" + " <Country Code=\"GBR\">Storbritannien</Country>\n" + " </Location>\n" + " <ConfirmationCode>982674693</ConfirmationCode>\n" + " <Cost>\n" + " <Amount>751.08</Amount>\n" + " <Currency Code=\"SEK\">Swedish Krona</Currency>\n" + " </Cost>\n" + " <OutOfPolicyReasons/>\n" + " </HOTEL>\n" + " </HotelSegment>\n" + " </Segments>\n" + " <Invoicing>\n" + " <CompanyCode>28781</CompanyCode>\n" + " <ClientNumber>28781</ClientNumber>\n" + " <ClientRequisition>claude.christensson@wirelesscar.com</ClientRequisition>\n" + " <ClientReference>689100277</ClientReference>\n" + " <ClientCostCenter>\n" + " <CostCenter Code=\"CC1\">\n" + " <Label>Legal Entity</Label>\n" + " <Value>WirelessCar Sweden AB</Value>\n" + " </CostCenter>\n" + " <CostCenter Code=\"CC2\">\n" + " <Label>Cost Center</Label>\n" + " <Value>989502</Value>\n" + " </CostCenter>\n" + " </ClientCostCenter>\n" + " </Invoicing>\n" + "</EGE_Booking>\n"; final Pattern pattern = Pattern.compile(regex); 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