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

/
/
gm

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 = "^\"(.*)\" (.*), (.*)"; final String string = "Description\n" + "\"Mulligan\" neutered male, Brindle Bullmastiff\n" + "\"Tiny\" male, tan and white Boxer mix\n" + "\"Charlie\" neutered male, black and white Labrador Retriever mix \n" + "\"Nala\" spayed female, white and brown brindle Pit Bull mix\n" + "\"Lexie\" female, white and black Pit Bull \n" + "\"Holly\" Spayed female, white Labrador/Pitbull mix\n" + "\"Lincoln\" male, fawn and white Pit Bull Terrier\n" + "\"Sparkles\" spayed female, Brindle Plott Hound mix\n" + "\"Missy\" Spayed Female, red/white Pitbull mix\n" + "\"Rita\" female, brown Australian Shepherd \n" + "\"Miles Davis\" female, gold/white Golden Retriever \n" + "\"Lacy\" spayed female, Labrador Retriever Mix\n" + "\"Clementine\" spayed female, black and white Austrailian Cattle dog\n" + "\"Coronel\" Male, Tan/Black German Shepherd mix\n" + "\"Lady Bug\" spayed female, white/black Pit bull/Jack Russell mix\n" + "\"Buddy\" male, blue brindle and white Pitbull mix\n" + "\"Boomer\" neutered brown Pit Bull Mix\n" + "\"Weezer\" female, Tan/Brown German Shepherd\n" + "\"Little Girl\" spayed female, brown brindle and white Bull Terrier\n" + "\"Diva\" intact female, tri-color Pit Bull\n" + "\"Jack\" neutered male, red/white Labrador Retriever mix \n" + "\"Salty\" male, brown and white Boxer\n" + "\"G\" male, brown Pit Bull/Boxer mix \n" + "\"Keely\" spayed female, Red Labrador Retriever mix\n" + "\"Tyson\" neutered male, German Shepherd\n" + "\"Tug\" male, brown merle and white Queensland Heeler mix\n" + "\"Shebba\" female, white Pit Bull mix \n" + "\"Blue\" male, blue Pit Bull mix\n" + "\"Pinky\" female, white Boxer mix\n" + "\"Ladybird\" Spayed female, yellow brindle and white Pit Bull mix\n" + "\"Dozer\" neutered male, white and red Rhodesian Ridgeback\n" + "\"Lahlo\" spayed female, tan Boxer mix\n" + "\"Maya\" spayed female, brown/white Pitbull mix\n" + "\"Cinnamon\" female, red and white Border Collie \n" + "\"Taz\" neutered male, brown brindle Boxer mix\n" + "\"Lily\" female, black and white Chihuahua\n" + "\"Abbo\" neutered male, white/brown Great Pyrenees mix \n" + "\"Milo\" neutered male, white/brown, German Short-haired Pointer\n" + "\"Lia\" spayed female, white/black Pit Bull/Jack Russell mix\n" + "\"Sissy\" female, tan and black German Shepherd\n" + "\"Nippy\" female, black and tan Shepherd mix\n" + "\"Ginger\" spayed female, red and white American Fox Terrier mix\n" + "\"Jonah\" female, brown and white Pit Bull mix\n" + "\"Diego\" neutered male, cream and white Great Pyrenees\n" + "\"June\" female, Brindle Pit Bull Terrier \n" + "\"Maia\" female, white/tan Pit Bull mix\n" + "\"Iko\" neutered male, Brown Brindle Catahoula mix\n" + "\"Zues\" neutered male, blue and white Great Dane\n" + "\"Tank\" neutered, black/grey German Wire-haired Pointer \n" + "\"Bumpy\" neutered male, white and black Bull Terrier\n" + "\"Negro\" neutered male, black, tan and white Chihuahua mix\n" + "\"Lucy\" spayed female, brown brindle and white Boxer mix\n" + "\"Austin\" male, red merle Australian Shepherd\n" + "\"Aries\" spayed female, blue Cane Corso\n" + "\"Bella\" spayed female, Tan and White Pit Bull mix\n" + "\"Gucio\" male, black Giant Schnauzer\n" + "\"Kilo\" neutered male, red and white Pit Bull mix\n" + "\"Chuy\" spayed female, brown brindle and white Boxer mix\n" + "\"Flint\" neutered male, blue Blue Lacy mix\n" + "\"Sydney\" spayed female, Tricolor/Black Beagle \n" + "\"Sunny\" Neutered Male, Brown/Tan Shepherd mix\n" + "\"Lucky\" male, black and tri-colored Chihuahua\n" + "\"Cleo\" female, black Labrador Retriever mix "; final String subst = "$1\\t$2\\t$3"; final Pattern pattern = Pattern.compile(regex, 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