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

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 = "\\b(10\\.[0-9]{4,}(?:\\.[0-9]+)*\\/(?:(?![\\\"&\\'])\\S)+)\\b"; final String string = "Herbst, D. M., Griffith, N. R., & Slama, K. M. (2014). Rodeo cowboys: Conforming to masculine norms and help-seeking behaviors for depression. Journal of Rural Mental Health, 38, 20–35. http://dx.doi.org/10.1037/rmh0000008\n\n" + "Herbst, D. M., Griffith, N. R., & Slama, K. M. (2014). Rodeo cowboys: Conforming to masculine norms and help- seeking behaviors for depression. Journal of Rural Mental Health, 38, 20–35. doi:10.1037/rmh0000008\n\n" + "Example: https://doi.org/10.5468/ogs.2016.59.1.1\n\n" + "\"Quantum tomography: Measured measurement\", Markus Aspelmeyer, nature physics January 2009, Volume 5, No 1, pp11-12; [doi:10.10.1038/nphys1170]\n\n" + "Held, Gilbert. Internetworking LANs and WANs (Second Edition), John Wiley & Sons, 1998, Published Online 05 Oct 2001. Chapter 1, Network Concepts (p 1-30) [doi:10.1002/0470841559.ch1]\n\n" + "Irino, T; Tada, R (2009): Chemical and mineral compositions of sediments from ODP Site 127-797. Geological Institute, University of Tokyo. [doi:10.1594/PANGAEA.726855]\n" + "Earthquake Event, Authored by Automated System:\n\n" + "Geofon operator (2009): GEOFON event gfz2009kciu (NW Balkan Region) GeoForschungsZentrum Potsdam(GFZ). [doi:10.1594/GFZ.GEOFON.gfz2009kciu]\n\n" + "Kraus, Stefan; del Valle, Rodolfo (2008): Geological map of Potter Peninsula (King George Island, South Shetland Islands, Antarctic Peninsula). Instituto Antártico Chileno, Punta Arenas, Chile & Instituto Antártico Argentino, Buenos Aires, Argentina. [doi:10.1594/PANGAEA.667386]\n\n" + "B. Kirchhof (2009) Silicone oil bubbles entrapped in the vitreous base during silicone oil removal, Video Journal of Vitreoretinal Surgery. [doi: 10.3207/2959859860]"; final Pattern pattern = Pattern.compile(regex, Pattern.CASE_INSENSITIVE | Pattern.MULTILINE); 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