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 = "^(?<artist>[\\w ]+)\\/(?<album>[\\w ]+)\\/(( - )|(\\d+)|\\k<artist>|\\k<album>|[_])*(?<name>.+)(?<ext>\\.(flac|mp3))$"; final String string = "Infected Mushroom/\n" + "Infected Mushroom/Vicious Delicious\n" + "Infected Mushroom/Vicious Delicious/01 - Infected Mushroom - Becoming Insane.flac\n" + "Infected Mushroom/Vicious Delicious/02 - Infected Mushroom - Artillery.flac\n" + "Infected Mushroom/Vicious Delicious/03 - Infected Mushroom - Vicious Delicious.flac\n" + "Infected Mushroom/Vicious Delicious/04 - Infected Mushroom - Heavyweight.flac\n" + "Infected Mushroom/Vicious Delicious/05 - Infected Mushroom - Suliman.flac\n" + "Infected Mushroom/Vicious Delicious/06 - Infected Mushroom - Forgive Me.flac\n" + "Infected Mushroom/Vicious Delicious/07 - Infected Mushroom - Special Place.flac\n" + "Infected Mushroom/Vicious Delicious/08 - Infected Mushroom - In Front Of Me.flac\n" + "Infected Mushroom/Vicious Delicious/09 - Infected Mushroom - Eat It Raw.flach Mushroom - Before.flac\n" + "Infected Mushroom/Army of Mushrooms\n" + "Infected Mushroom/Army of Mushrooms/01 - Never Mind.flac\n" + "Infected Mushroom/Army of Mushrooms/02 - Nothing to Say.flac\n" + "Infected Mushroom/Army of Mushrooms/03 - Send Me an Angel.flac\n" + "Infected Mushroom/Army of Mushrooms/04 - U R So Fucked.flac\n" + "Infected Mushroom/Army of Mushrooms/05 - The Rat.flac\n" + "Infected Mushroom/Army of Mushrooms/06 - Nation of Wusses.flac\n" + "Infected Mushroom/Army of Mushrooms/07 - Wanted To.flac\n" + "Infected Mushroom/Army of Mushrooms/08 - Serve My Thirst.flac\n" + "Infected Mushroom/Army of Mushrooms/09 - I Shine.flac\n" + "Infected Mushroom/Army of Mushrooms/10 - Drum n' Bassa.flac\n" + "Infected Mushroom/Army of Mushrooms/11 - The Pretender.flac\n" + "Infected Mushroom/Army of Mushrooms/12 - The Messenger 2012.flac\n" + "Infected Mushroom/Converting Vegetarians II\n" + "Infected Mushroom/Converting Vegetarians II/01 - She Zoremet.flac\n" + "Infected Mushroom/Converting Vegetarians II/02 - Yamakas in Space.flac\n" + "Infected Mushroom/Converting Vegetarians II/03 - Sense of Direction.flac\n" + "Infected Mushroom/Converting Vegetarians II/04 - Animatronica.flac\n" + "Infected Mushroom/Converting Vegetarians II/05 - Feelings.flac\n" + "Infected Mushroom/Converting Vegetarians II/06 - Pink Froid.flac\n" + "Infected Mushroom/Converting Vegetarians II/07 - Demons of Pain.flac\n" + "Infected Mushroom/Converting Vegetarians II/08 - Zoan Zound.flac\n" + "Infected Mushroom/Converting Vegetarians II/09 - Blue Swan 5.flac\n" + "Infected Mushroom/Converting Vegetarians II/10 - Fields of Grey (feat. Sasha Grey).flac\n" + "Infected Mushroom/Converting Vegetarians II/11 - Leopold.flac\n" + "Infected Mushroom/Converting Vegetarians II/12 - On the Road Again.flac\n" + "Infected Mushroom/Converting Vegetarians II/13 - Stuck in a Loop.flac\n" + "Infected Mushroom/Converting Vegetarians II/14 - Mexicali.flac\n" + "Infected Mushroom/Converting Vegetarians II/15 - The Surgeon.flac\n" + "Infected Mushroom/Legend of the Black Shawarma\n" + "Infected Mushroom/Legend of the Black Shawarma/Infected Mushroom - Legend of the Black Shawarma - 01 - Poquito Mas.flac\n" + "Infected Mushroom/Legend of the Black Shawarma/Infected Mushroom - Legend of the Black Shawarma - 02 - Sa'eed.flac\n" + "Infected Mushroom/Legend of the Black Shawarma/Infected Mushroom - Legend of the Black Shawarma - 03 - End of the Road.flac\n" + "Infected Mushroom/Legend of the Black Shawarma/Infected Mushroom - Legend of the Black Shawarma - 04 - Smashing the Opponent (feat. Jonathan Davis).flac\n" + "Infected Mushroom/Legend of the Black Shawarma/Infected Mushroom - Legend of the Black Shawarma - 05 - Can't Stop.flac\n" + "Infected Mushroom/Legend of the Black Shawarma/Infected Mushroom - Legend of the Black Shawarma - 06 - Herbert the Pervert.flac\n" + "Infected Mushroom/Legend of the Black Shawarma/Infected Mushroom - Legend of the Black Shawarma - 07 - Killing Time (feat. Perry Ferrell).flac\n" + "Infected Mushroom/Legend of the Black Shawarma/Infected Mushroom - Legend of the Black Shawarma - 08 - Project 100.flac\n" + "Infected Mushroom/Legend of the Black Shawarma/Infected Mushroom - Legend of the Black Shawarma - 09 - Franks.flac\n" + "Infected Mushroom/Legend of the Black Shawarma/Infected Mushroom - Legend of the Black Shawarma - 10 - Slowly.flac\n" + "Infected Mushroom/Legend of the Black Shawarma/Infected Mushroom - Legend of the Black Shawarma - 11 - The Legend of the Black Shawarma.flac\n" + "Infected Mushroom/Legend of the Black Shawarma/Infected Mushroom - Legend of the Black Shawarma - 12 - Riders on the Storm (Infected Mushroom Remix).flac\n" + "Infected Mushroom/Pink Nightmares\n" + "Infected Mushroom/Pink Nightmares/01_Pink_Nightmares_Album_Mix.flac\n"; final String subst = "\\g<name>\\g<ext>"; 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