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
Processing...

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 = "(?<entropy>\\d+)\\s*bit\\s*(?<algo>\\S+)\\s*key\\s*(?<pubkeyid>[^,]+)"; final String string = "gpg: data source: http://162.213.33.9:11371\n" + "(1) Ferry Huberts <hubferry@amazon.com>\n" + " 2048 bit RSA key 6E2B662831D0CC10, created: 2018-02-07\n" + "(2) 2048 bit RSA key 0BC0283EFDAEF030, created: 2018-03-10\n" + "(3) Josh Glover (Unix Systems Administrator) <jglover@amazon.com>\n" + " Josh Glover (Unix Systems Administrator) <jglover@amazon.co.jp>\n" + " 1024 bit DSA key E17F5B227E900E40, created: 2005-12-06\n" + "(4) 4096 bit RSA key 24B92E0779F635B0, created: 2015-12-23\n" + "(5) 1024 bit DSA key D7BA5D43FBF27CC0, created: 2011-01-27\n" + "(6) 4096 bit RSA key FB2FA8D887FC1DC0, created: 2017-10-04\n" + "(7) 2048 bit RSA key 190232BEA3460DD0, created: 2012-11-28\n" + "(8) Mark Caudill <markca@amazon.com>\n" + " 1024 bit DSA key 20640006F66A12E0, created: 2009-02-17\n" + "(9) Xenia Kleopatra (Xenia Kleopatra) <xllojova@amazon.com>\n" + " 2048 bit RSA key 8160348321F61431, created: 2016-03-03\n" + "(10) 4096 bit RSA key 51979A726FE02431, created: 2016-03-24\n" + "(11) MitchellCutler (This is my Public Key Certificate) <cutlermc@amazon.co\n" + " 2048 bit RSA key FE7B4D2A2CAF8A31, created: 2015-04-23\n" + "(12) Amazon Elasticache (Signing key for Elasticache maven artifacts) <aws-\n" + " 2048 bit RSA key 8E929B5B774E3E31, created: 2016-10-19\n" + "(13) 2048 bit RSA key 0A4F0C8F5B5DE981, created: 2012-05-11\n" + "(14) 1024 bit RSA key AD960C3C09043347, created: 1998-09-04\n" + "(15) Eric Brandwine <ericbran@amazon.com>\n" + " 2048 bit RSA key 605E1724D413B9D1, created: 2010-03-24\n" + "Keys 1-15 of 100 for \"amazon.com\". gpg: Sorry, we are in batchmode - can't get input"; 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