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

/
/
s

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 = "Subject:.+?Security ID:\\t{1,}(?<mswin_security_id>.+?)\\n"; final String string = "{ [-]\n" + " @timestamp: 2021-01-13T14:30:13.835Z\n" + " @version: 1\n" + " cloud_service_name: MOS-WIN\n" + " id: fd5c4ce8-b5cb-4cb4-a1e5-82c7e531673d\n" + " log_entry: An account was successfully logged on.\n\n" + "Subject:\n" + " Security ID: S-1-5-18\n" + " Account Name: PT1-X-CHRDB-1$\n" + " Account Domain: DRACO910\n" + " Logon ID: 0x3E7\n\n" + "Logon Information:\n" + " Logon Type: 44\n" + " Restricted Admin Mode: -\n" + " Virtual Account: No\n" + " Elevated Token: Yes\n\n" + "Impersonation Level: Impersonation\n\n" + "New Logon:\n" + " Security ID: S-1-5-21-3515936613-886961063-2664560780-6781\n" + " Account Name: ABB-ESC-9e8ec\n" + " Account Domain: DRACO910\n" + " Logon ID: 0xF0D94929\n" + " Linked Logon ID: 0x0\n" + " Network Account Name: -\n" + " Network Account Domain: -\n" + " Logon GUID: {6D3F87DE-7E78-7F6F-EF45-BFC1FC1C1BFE}\n\n" + "Process Information:\n" + " Process ID: 0x1b0\n" + " Process Name: C:\\Program Files\\EMC NetWorker\\nsr\\bin\\nsrexecd.exe\n\n" + "Network Information:\n" + " Workstation Name: PT1-X-CHRDB-1\n" + " Source Network Address: -\n" + " Source Port: -\n\n" + "Detailed Authentication Information:\n" + " Logon Process: Advapi \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 session is created. It is generated on the computer that was accessed.\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 occurred. The most common types are 2 (interactive) and 3 (network).\n\n" + "The New Logon fields indicate the account for whom the new logon was created, i.e. the account that was logged on.\n\n" + "The network 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 impersonation level field indicates the extent to which a process in the logon session can impersonate.\n\n" + "The authentication information fields provide detailed information about this specific logon request.\n" + " - Logon GUID is a unique identifier that can be used to correlate this event with a KDC event.\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.\n" + " log_type: SECURITY\n" + " tenant_name: draco-910\n" + " timestamp: 2021-01-13T14:30:08.442Z\n" + " version: 1.0\n" + "}"; final Pattern pattern = Pattern.compile(regex, Pattern.DOTALL); 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