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

/
/
gm

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 = "(^[a-zA-Z._-]+)\\(([0-9]+)\\) : (error.*)"; final String string = ".\\include\\intentionally_initally_empty.txt\n" + "1 File(s) copied\n\n" + "// Compiling galileo.sma ... Current time is: 15:26:16,93 - 11/09/2016\n\n" + "Welcome to the AMX Mod X 1.8.1-300 Compiler.\n" + "Copyright (c) 1997-2013 ITB CompuPhase, AMX Mod X Team\n\n" + "galileo.sma(1026) : error 017: undefined symbol \"nextmap_plugin_init\"\n" + "galileo.sma(1032) : error 017: undefined symbol \"register_dictionary_colored\"\n" + "galileo.sma(1208) : error 017: undefined symbol \"nomination_clearAll\"\n" + "gali_leo.sma(1288) : error 017: undefined symbol \"get_realplayersnum\"\n" + "galileo.sma(1455) : error 017: undefined symbol \"serverChangeLevel\"\n" + "galileo.sma(1524) : error 017: undefined symbol \"saveEndGameLimits\"\n" + "gali-leo.sma(1558) : error 017: undefined symbol \"map_getNext\"\n" + "galileo.sma(1572) : error 017: undefined symbol \"map_getNext\"\n" + "galileo.sma(1620) : error 017: undefined symbol \"saveCurrentMapCycleSetting\"\n" + "galileo.sma(2294) : error 017: undefined symbol \"cancelVoting\"\n" + "galileo.sma(2312) : error 017: undefined symbol \"cancelVoting\"\n" + "galileo.sma(2389) : error 017: undefined symbol \"map_getMinutesElapsedInteger\"\n" + "galileo.sma(2389) : error 017: undefined symbol \"saveEndGameLimits\"\n" + "galileo.sma(2390) : error 017: undefined symbol \"saveEndGameLimits\"\n" + "galileo.sma(2391) : error 017: undefined symbol \"saveEndGameLimits\"\n" + "galileo.sma(2392) : error 017: undefined symbol \"saveEndGameLimits\"\n" + "galileo.sma(2942) : error 017: undefined symbol \"get_realplayersnum\"\n" + "galileo.sma(2954) : error 017: undefined symbol \"get_realplayersnum\"\n" + "galileo.sma(3062) : error 017: undefined symbol \"get_realplayersnum\"\n" + "galileo.sma(3169) : error 017: undefined symbol \"map_isInMenu\"\n" + "galileo.sma(3352) : error 017: undefined symbol \"get_realplayersnum\"\n" + "galileo.sma(3425) : error 017: undefined symbol \"getPlayerNominationMapIndex\"\n" + "galileo.sma(3471) : error 017: undefined symbol \"get_realplayersnum\"\n" + "galileo.sma(3545) : error 017: undefined symbol \"color_print\"\n" + "galileo.sma(3551) : error 017: undefined symbol \"color_print\"\n" + "galileo.sma(3627) : error 017: undefined symbol \"color_print\"\n\n" + "Compilation aborted.\n" + "26 Errors.\n" + "Could not locate output file compiled/galileo.amx (compile failed).\n\n" + "Took 0:00:01,54 seconds to run this script.\n\n" + "[Finished in 2.3s]"; 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