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

r"
"

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 = "(?P<device>\\w+-\\w+)\\s+(?P<ObjectDetected>\\w+.\\w+.\\w+.\\w+.)(?P<date>\\w+,\\s+\\w+\\s+\\d+,\\s+\\d+)\\s+(?P<time>\\d+:\\d+:\\d+\\s+\\w{1,2})\\s+(?P<Path>[A-Z]:\\\\.+)\\s+(?P<Type>Trojan|Virus|Worm)\\s+((?P<Action>).+)((?P<Account>)((DOTIN\\\\)).+)\\s+(?P<AVApplication>(Kaspersky).+)(?P<version>\\d+.\\d+.\\d+.\\d+)\\s+((?P<Visibledate>(Monday,|Saturday,|Sunday,|Tuesday,|Wednesday,|Thursday,|Friday,))\\s+(January|February|March|April|May|June|July|August|September|October|November|December)\\s+(\\d+,\\s+\\d+\\s+\\d+:\\d+:\\d+\\s+\\w+))\\s((?P<lastConnection>(Monday,|Saturday,|Sunday,|Tuesday,|Wednesday,|Thursday,|Friday,))\\s+(January|February|March|April|May|June|July|August|September|October|November|December)\\s+\\d+,\\s+\\d+\\s+\\d+:\\d+:\\d+\\s+(PM|pm|AM|am))\\s+(?P<IP>\\d+.\\d+.\\d+.\\d+)\\s+(?P<ClientName>\\w+-\\w+)\\s+(?P<Domain>\\w+)"; final String string = "10.20.10.0 AMIRI-PC Trojan.Win32.Waldek.ajd Wednesday, January 27, 2016 8:05:18 AM E:\\​ \\​{0732260D-4643-427C-A22B-F0DFA8EDE30D}.{EE225B7C-E421-47D2-A65B-AE9AB046A5F2} Trojan Result: Untreated: Trojan.Win32.Waldek.ajd User: DOTIN\\​t.amiri (Active user) Object: e:\\​ \\​{0732260d-4643-427c-a22b-f0dfa8ede30d}.{ee225b7c-e421-47d2-a65b-ae9ab046a5f2} DOTIN\\​T.AMIRI Kaspersky Endpoint Security 10 Service Pack 1 for Windows 10.2.2.10535 Monday, February 15, 2016 3:11:38 PM Monday, February 15, 2016 3:11:38 PM 10.20.10.28 AMIRI-PC DOTIN \n\n" + "------------------------------------------------------------\n\n" + "(^Trojan)\n" + "((DOTIN\\\\)(w+.\\w+))\\s+(kaspersky)\n" + "(Monday,|Saturday,|Sunday,|Tuesday,|Wednesday,|Thursday,|Fridy,)\n\n" + "&&(\\s+(February)|)\\s+\\d+\\s+\\d+,\\s+\\d+\\s+(\\d+:\\d+:\\d+\\s+\\w+\\s+\\w+\n" + "(?P<Type>Trojan|Virus|Worm)\n" + "+(?P<Account>)\n" + "(?P<AVApplication>\n" + "?P<Visible>(Monday,|Saturday,|Sunday,|Tuesday,|Wednesday,|Thursday,|Friday,)\\s+(January|February|March|April|May|June|July|August|September|October|November|December)\n" + "?P<version>\n" + "?P<lastConnection>\\"; 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