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 = "https:(.*?)\\/track\\/(.*?)\\?(.*)"; final String string = "https://open.spotify.com/track/7cy1bEJV6FCtDaYpsk8aG6?si=4NrCtBYRRt6QIEggvr5-UQ\n" + "https://open.spotify.com/track/2mKS9ECgxNSRQgmQO7CY8x?si=70ua2XGPTvy5tg3tAfSIHQ\n" + "https://open.spotify.com/track/1rqqCSm0Qe4I9rUvWncaom?si=j8IHrLXASjmgSOc77seefQ\n" + "https://open.spotify.com/track/7MRY4VpCuZvBmFda6ZCk2G?si=BIlDAq22RkSb559U3Ymdgw\n" + "https://open.spotify.com/track/1yG1OpMiV8WtDeOYEBvNW8?si=VSOSzYHCQGW7-DZoDTq15A\n" + "https://open.spotify.com/track/0zYkf4pCiGAhEp5Z3iUkml?si=DQ0o-GGRQfmqABxDcqeywQ\n" + "https://open.spotify.com/track/4HCcvFdHfwR2u3WPPPVRv6?si=N_l1p_fMTXSYdEA2V4uKKg\n" + "https://open.spotify.com/track/6A3ff44rkAsNUPq5ZpG0Lw?si=X6E_z8ClSm-gqOh_PNJ8aA\n" + "https://open.spotify.com/track/1owidcBLuyqbtlJRWyRubJ?si=AfuGmcQ4RL6znQrBnHNsUQ\n" + "https://open.spotify.com/track/72OeMxh65OcA6riQ7fRH6c?si=jXksouMoTTy9gHiusgAN3Q\n" + "https://open.spotify.com/track/1PqZRvgKb2OepsA7aeb64y?si=n7RCpDM_TOeAsSSgJqecCQ\n" + "https://open.spotify.com/track/4K8pmNLIAhetFRpEBGV0dJ?si=O_Vwez-xQ-ufDqeSjJmYjw\n" + "https://open.spotify.com/track/3DVNUiBeYKbp7JvvcrfqZB?si=vRTYM_lXRP--LwoFg44M8Q\n" + "https://open.spotify.com/track/4w2iAP3X4FkpPb5kjRdIDx?si=w0PH7da9RgeWspRVYrFeFw\n" + "https://open.spotify.com/track/0Y2QWrhPh6ATyaWYT0QLIR?si=hwnF_-1aTcioBOSJLHNE1w\n" + "https://open.spotify.com/track/4pkZNPC6yeMnQABwkTmsR6?si=JC6rPKnBQRCGF6NP9I6QKg\n" + "https://open.spotify.com/track/5rR1C059TESZuNiiYEzZBa?si=-ncveFyxS3KDa7Yf54opZg\n" + "https://open.spotify.com/track/6aFc0W6xVS9kN9E9NGekAl?si=9Jiu-bANSuaPPjJOE_b5GQ\n" + "https://open.spotify.com/track/6ZF6PsmadIgyuxp0wqD9qO?si=HardRQQzSXGMxiscNsuuIQ\n" + "https://open.spotify.com/track/7HhawuOJ17618C4VJfJn2K?si=Ve0FWw02SDuhA3FO9ZRfVA\n" + "https://open.spotify.com/track/2ZFAzZ5uluMR8TeO6YEy52?si=QYw76ZYDTAqmigwp-4K0_w\n" + "https://open.spotify.com/track/7IO8jHHbV9P4VtcfeGvEZy?si=xp4fWYXVQP-NBhjF6M6LkQ\n" + "https://open.spotify.com/track/0CLYfCWlqR1zB6Wqi6VTwy?si=_yiWBH82SUmNfKrcoUFSXw\n" + "https://open.spotify.com/track/4PAT0WuPzHOn94bP0BYZUz?si=oPcZRxB0TYGbjzvz54ZkPw\n" + "https://open.spotify.com/track/5XKDliIGPTUnNRwRZsd0oN?si=okAtielaT2ChEL2vK3DV8Q\n" + "https://open.spotify.com/track/5fpj84RsT9cOTfWUCxBTXu?si=5He0nt3oQzSipKrtwaKJ-A"; final String subst = "spotify:track:$2"; 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