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

/
/
g

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 = "(?m)EventCode\\s*=\\s*4625|Caller Process Name.*svchost.exe"; final String string = "02/11/2020 11:51:38 AM\n" + "LogName=Security\n" + "SourceName=Microsoft Windows security auditing.\n" + "EventCode=4625\n" + "EventType=0\n" + "Type=Information\n" + "ComputerName=MelissaNBT3RG22\n" + "TaskCategory=Logon\n" + "OpCode=Info\n" + "RecordNumber=40702\n" + "Keywords=Audit Failure\n" + "Message=An account failed to log on.\n\n" + "Subject:\n" + " Security ID: S-1-5-18\n" + " Account Name: MELISSANBT3RG22$\n" + " Account Domain: WORKGROUP\n" + " Logon ID: 0x3E7\n\n" + "Logon Type: 2\n\n" + "Account For Which Logon Failed:\n" + " Security ID: S-1-0-0\n" + " Account Name: MNesavich\n" + " Account Domain: MELISSANBT3RG22\n\n" + "Failure Information:\n" + " Failure Reason: Unknown user name or bad password.\n" + " Status: 0xC000006D\n" + " Sub Status: 0xC000006A\n\n" + "Process Information:\n" + " Caller Process ID: 0x848\n" + " Caller Process Name: C:\\Windows\\System32\\svchost.exe\n\n" + "Network Information:\n" + " Workstation Name: MELISSANBT3RG22\n" + " Source Network Address: 127.0.0.1\n" + " Source Port: 0\n\n" + "Detailed Authentication Information:\n" + " Logon Process: User32 \n" + " Authentication Package: Negotiate\n" + " Transited Services: -\n" + " Package Name (NTLM only): -\n" + " Key Length: 0\n\n" + "This event is generated when a logon request fails. It is generated on the computer where access was attempted.\n\n" + "The Subject fields indicate the account on the local system which requested the logon. This is most commonly a service such as the Server service, or a local process such as Winlogon.exe or Services.exe.\n\n" + "The Logon Type field indicates the kind of logon that was requested. The most common types are 2 (interactive) and 3 (network).\n\n" + "The Process Information fields indicate which account and process on the system requested the logon.\n\n" + "The Network Information fields indicate where a remote logon request originated. Workstation name is not always available and may be left blank in some cases.\n\n" + "The authentication information fields provide detailed information about this specific logon request.\n" + " - Transited services indicate which intermediate services have participated in this logon request.\n" + " - Package name indicates which sub-protocol was used among the NTLM protocols.\n" + " - Key length indicates the length of the generated session key. This will be 0 if no session key was requested."; 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