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

/
/
gim

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 = "^\\/ignition-interlock-device\\/([a-z]*?)\\/(locations)?\\/smart-start-of-([a-z0-9-]*?)(\\/)?$"; final String string = "/ignition-interlock-device/colorado/locations/smart-start-of-alamosa/\n" + "/ignition-interlock-device/colorado/locations/smart-start-of-auburn-2/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-beverly/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-boca-raton-2/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-brownsville/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-camrose/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-carbondale/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-carson-city/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-centereach/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-charleston-2/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-charleston/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-danielson/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-defuniak-springs/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-deland-2/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-durango/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-farmington/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-framingham/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-gallatin/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-gresham/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-gypsum/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-hialeah/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-holly-hill-2/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-honolulu-3/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-huntington/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-huntsville/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-kennesaw/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-kennewick/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-kissimmee-2/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-la-crosse/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-laramie/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-lawton/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-longwood/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-malden/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-mckinney/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-medford/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-middletown-2/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-middletown/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-mildura/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-new-port-richey/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-norco/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-ocala-2/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-palm-bay-2/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-palm-bay/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-panama-city-2/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-port-charlotte-2/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-richmond-3/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-saint-paul-2/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-san-marcos/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-santa-ana/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-show-low/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-staunton/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-tallahassee-2/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-titusville/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-uppsala-2/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-van-wert/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-west-monroe/\n" + "/ignition-interlock-device/florida/locations/smart-start-of-west-palm-beach-2/"; final String subst = "/locations/?location_redirect=$3&state=$1"; final Pattern pattern = Pattern.compile(regex, Pattern.CASE_INSENSITIVE | Pattern.MULTILINE); final Matcher matcher = pattern.matcher(string); // The substituted value will be contained in the result variable final String result = matcher.replaceAll(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