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

/
/
gm

Test String

Code Generator

Generated Code

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "<Data Name=\"(.*?)\">(.*?)<\\/Data>"; final String string = "<Event><System><Provider Name=\"Linux-Sysmon\" Guid=\"{ff032593-a8d3-4f13-b0d6-01fc615a0f97}\"/><EventID>3</EventID><Version>5</Version><Level>4</Level><Task>3</Task><Opcode>0</Opcode><Keywords>0x8000000000000000</Keywords><TimeCreated SystemTime=\"2023-11-13T13:34:45.693615000Z\"/><EventRecordID>140108</EventRecordID><Correlation/><Execution ProcessID=\"24493\" ThreadID=\"24493\"/><Channel>Linux-Sysmon/Operational</Channel><Computer>computername</Computer><Security UserId=\"0\"/></System><EventData><Data Name=\"RuleName\">-</Data><Data Name=\"UtcTime\">2023-11-13 13:34:45.697</Data><Data Name=\"ProcessGuid\">{ba131d2e-2a52-6550-285f-207366550000}</Data><Data Name=\"ProcessId\">64284</Data><Data Name=\"Image\">/opt/splunkforwarder/bin/splunkd</Data><Data Name=\"User\">root</Data><Data Name=\"Protocol\">tcp</Data><Data Name=\"Initiated\">true</Data><Data Name=\"SourceIsIpv6\">false</Data><Data Name=\"SourceIp\">x.x.x.x</Data><Data Name=\"SourceHostname\">-</Data><Data Name=\"SourcePort\">60164</Data><Data Name=\"SourcePortName\">-</Data><Data Name=\"DestinationIsIpv6\">false</Data><Data Name=\"DestinationIp\">x.x.x.x</Data><Data Name=\"DestinationHostname\">-</Data><Data Name=\"DestinationPort\">8089</Data><Data Name=\"DestinationPortName\">-</Data></EventData></Event>"; 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