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

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 = "Abstract title:(?:.|\\r?\\n\\w)*"; final String string = "Prof. Imperdiet montes, metus elementum eleifend eget eget adipiscing augue.\n" + "Abstract title: Lorem ipsum dolor sit amet, consectetuer adipiscing\n\n" + "A, nec, quam eleifend quis, magnis sit pretium. leo augue. amet, elit. vel\n\n" + "Vel, dis eget nascetur justo. imperdiet consequat et sit Nam Aenean a, Quisque\n" + "Enim. a, dui. Aenean lorem Phasellus commodo quis, pretium ultricies nascetur\n" + "tincidunt. sem. vitae,\n" + "montes, tellus. amet, venenatis natoque enim. fringilla\n" + "quis, vitae, Aenean Etiam viverra ipsum dapibus ut elementum Aenean Lorem eget,\n" + "nisi mollis Curabitur Quisque Aenean rhoncus sociis justo, sem. justo, vel\n" + "Aenean ultricies nec, eu laoreet.\n\n" + "Dr. Enim. vitae, feugiat in, Aenean\n" + "Abstract title: Massa. sociis dis dapibus dolor semper ipsum\n" + "jalor\n\n" + "Semper tincidunt. ullamcorper commodo magnis viverra pede elit. eget aliquet\n" + "eleifend vel, eleifend feugiat pede Vivamus ridiculus vitae, a, ligula, et Nulla\n" + "ligula vulputate ac, nisi. enim dapibus. Donec metus In sit dolor Nam ultricies\n" + "imperdiet. pellentesque Cras eu, massa quis porttitor parturient varius ut,\n" + "Phasellus arcu. pretium. quam augue. eu, adipiscing felis, enim. ante,\n" + "vulputate Integer dui. ultricies a, dictum rutrum. Nullam nec, quis,\n" + "consequat Cum tellus. dis felis dolor. nulla Aliquam Donec massa. justo. in,\n" + "nascetur\n" + "Semper tincidunt. ullamcorper commodo magnis viverra pede elit. eget aliquet\n" + "eleifend vel, eleifend feugiat pede Vivamus ridiculus vitae, a, ligula, et Nulla\n\n\n" + "Dr. Justo. nisi elementum ante, Donec Aenean Nulla\n" + "Abstract title:\n\n" + "Aenean consectetuer leo penatibus eget imperdiet nisi. consequat\n" + "lorem pretium mus. \n\n" + "Prof. Dr. Aliquam metus semper\n" + "Abstract title: Aliquet augue. amet, enim ut justo, nec, eleifend lorem enim. nisi. ipsum\n" + "eleifend\n" + "More information will be available soon."; final Pattern pattern = Pattern.compile(regex, 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