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 = "^(?:.*[\\/\\\\])?(?<FileNameWithoutExtension>.*)\\.(.*)$"; final String string = "Taylor Swift - New Romantics.m4a\n" + "YT/Subto2mp3/Taylor Swift - New Terribly Romantics.m4a\n" + "Grow - Conan Blue (Official Video) has already been recorded in archive.m4a\n" + "PowerOptim Iol/Techno/(Official Video) Blue Burrow was already been recorded in archive - Bak.wm4\n" + "/Great Bun/Output Files/çè/Grow - Conan DARK (Official AUDIO) has already been recorded in archive.m4b\n" + "Matter Oil_9999.zip\n" + "Qpl$-pol.hrlp/perm.ui.pol/i op/doesn't matter.mp4\n" + "Small Laser4.m4a\n" + "manicur pliu/love is in the a°°_II+?§@R.txt\n" + "^Level09\\\\Power Pol\\energy.m4a\n" + "lollller_blllade 1987 (c)/super €/music_piece_.mp3\n" + "\\.\\.$./../../loli( u1990) _98.lop.pl/fil l/fill2asm.aile.asm.gz.zip\n" + "/Taylor Swift - New Romantics._m4a\n" + "\\$/Subto2/mp3/Taylor Swift -&- New Romantics.m4a\n" + "/Grow - Conan Gray (Official Video) has already been recorded in archive.m4a\n" + "C:\\PowerOptim Iol/Grow - The New Gray (Official Video) has been recorded [<1999>.wm4\n" + "/Great Bun/Output Files/çè/Grow - WiLlL(O)W Gray \"unofficial\" video has not been recorded in archive.m4b\n" + "/Matter Oil_9999.zip\n" + "file:///Qpl$-pol.hrlp/perm.ui.pol/i op/matter.mp4\n" + "/£¥«^6<4>à_»Laser4 ``[12{2%}32]deg`‘.webm\n" + "manicur pliu/great.power.great.responsibility?.gz.tar.zip\n" + "./poi kiol/greater.power.greater.responsibility!.gz.tar.zip\n" + "^Level09\\Power Pol\\energy.m4a\n" + "lollller_blllade 1987 (c)/super €/music_piece_.mp3\n" + "/The 'great' solitude of zorro #12/the 退ellent urge_for.mo.tar.gz\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