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

/
/
g

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 = ".*\\d\\s(\\d+-\\d+-\\d+T\\d+:\\d+:\\d+)(\\+\\d+:\\d+)\\s.*?\\s(\\d+,\\d+\\/\\d+\\/\\d+) .*? .*? .*? (\\d+:\\d+:\\d+),\\d+,THREAT,(url),(\\d+,\\d+\\/\\d+\\/\\d+ \\d+:\\d+:\\d+),(\\d+\\.\\d+\\.\\d+\\.\\d+),.*"; final String string = "<14>1 2017-07-17T12:06:14+00:00 PA-VM 1,2017/07/17 - - - 05:11:16,007055000020053,THREAT,url,1,2017/07/17 05:11:16,10.10.201.182,13.107.4.50,10.10.6.64,13.107.4.50,Segmented_to_PVT,,,ms-update,vsys1,User Zone,PUB Zone,ethernet1/1,ethernet1/3,Log_Forwarding_Profile,2017/07/17 05:11:16,41324,1,56881,80,3969,80,0x40b000,tcp,alert,\"au.download.windowsupdate.com/c/msdownload/update/software/secu/2017/07/windows10.0-kb4025339-x64_5_630b3945c0f68f2e3de0d8779d1e1e6c036e19ca.psf\",(9999),computer-and-internet-info,informational,client-to-server,437956,0x0,10.0.0.0-10.255.255.255,United States,0,,0,,,3,,,AppThreat-0-0,0x0,,,,,,0,0,0,0,0,,PA-VM,,,,get,0,,0,,N"; final Pattern pattern = Pattern.compile(regex); 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