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 = "(\\w+\\s+\\d{1,2}\\s+\\d\\d:\\d\\d:\\d\\d)\\s+([a-zA-Z0-9\\-]+)\\s+[SFIMS:]{1,6}\\s+\\[([a-zA-Z0-9_\\s]+)\\s+\\(([0-9a-z\\-]+)\\)\\]\\[(.+)\\]\\[(([0-9]+)\\:([0-9]+)\\:[0-9]+)\\]\\s+\\\"(.+)\\\"\\s+\\[Classification\\:\\s+(.+)\\]\\s+User\\:\\s+(.+)\\,\\s+Application\\:\\s+(.+)\\,\\s+Client:\\s+(.+)\\,\\s+App Protocol\\:\\s+(.+)\\,\\s+Interface Ingress\\:\\s+([a-zA-Z\\-\\_0-9]+)\\,\\s+Interface Egress\\:\\s+([a-zA-Z\\-\\_0-9]+)\\,\\s+Security Zone Ingress\\:\\s+([a-zA-Z\\-\\_0-9]+)\\,\\s+Security Zone Egress\\:\\s+([a-zA-Z\\-\\_0-9]+)\\,\\s+Context\\:\\s+([a-zA-Z\\-\\_0-9]+)\\,\\s+\\[Priority\\:\\s+([0-9]+)\\]\\s+\\{([A-Z]+)\\}\\s+([0-9.]+):([0-9]+)\\s->\\s([0-9.]+):([0-9]+)"; final String string = "Aug 7 17:47:38 Sourcefire3D SFIMS: [Primary Detection Engine (b363fd8a-2ec5-11de-91d7-e63c5c5fcc50)][ZurichConnect _ Osservazione][1:402:15] \"PROTOCOL-ICMP Destination Unreachable Port Unreachable\" [Classification: Misc Activity] User: Unknown, Application: Unknown, Client: Unknown, App Protocol: Unknown, Interface Ingress: s1p3, Interface Egress: s1p4, Security Zone Ingress: Internal, Security Zone Egress: External, Context: Unknown, SSL Flow Status: N/A, SSL Actual Action: N/A, SSL Certificate: 0000000000000000000000000000000000000000, SSL Subject CN: N/A, SSL Subject Country: N/A, SSL Subject OU: N/A, SSL Subject Org: N/A, SSL Issuer CN: N/A, SSL Issuer Country: N/A, SSL Issuer OU: N/A, SSL Issuer Org: N/A, SSL Valid Start Date: N/A, SSL Valid End Date: N/A, [Priority: 3] {ICMP} 172.23.33.201 -> 172.23.34.74, type: Destination Unreachable, code: Port unreachable"; final Pattern pattern = Pattern.compile(regex); final Matcher matcher = pattern.matcher(string); if (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