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 = "RJ.currentMP3Url = \\'([\\w\\\\\\/-]+)'"; final String string = " </div>\n" + " </div>\n" + " </div>\n" + " </div>\n" + "</section>\n\n" + "<script>\n" + " \n" + " RJ.currentMP3Url = 'mp3/Arian-Band-To-Ke-Ba-Man-Baashi';\n" + " RJ.currentMP3 = '40008';\n" + " RJ.currentMP3Type = 'mp3';\n" + " RJ.playingIndex = '0';\n" + " RJ.currentMP3Perm = 'Arian-Band-To-Ke-Ba-Man-Baashi';\n\n" + " RJ.currentAlbum = null;\n" + " RJ.currentPlaylist = null;\n\n" + " RJ.relatedMP3 = [{\"next\":\"Arian-Band-To-Ke-Ba-Man-Baashi\",\"index\":0},{\"next\":\"Arian-Band-Bargard\",\"index\":1},{\"next\":\"Arian-Band-Bishtar\",\"index\":2},{\"next\":\"Arian-Band-Deltangiha\",\"index\":3},{\"next\":\"Arian-Band-Faseleh\",\"index\":4},{\"next\":\"Arian-Band-Delam-Barat-Tang-Shodeh\",\"index\":5},{\"next\":\"Arian-Band-To-Moondi-o-Man\",\"index\":6},{\"next\":\"Arian-Band-Nemidoonam\",\"index\":7},{\"next\":\"Arian-Band-Baade-To\",\"index\":8},{\"next\":\"Arian-Band-Too-Cheshaye-Man-Negah-Kon\",\"index\":9},{\"next\":\"Arian-Band-Ta-Abaad\",\"index\":10},{\"next\":\"Arian-Band-Gole-Man\",\"index\":11},{\"next\":\"Arian-Band-Parvaz\",\"index\":12},{\"next\":\"Arian-Band-Gole-Aftab-Gardoon\",\"index\":13},{\"next\":\"Arian-Band-Parvaz-(Club-Mix)\",\"index\":14},{\"next\":\"Arian-Band-Ghasedak\",\"index\":15},{\"next\":\"Arian-Band-Baroon\",\"index\":16},{\"next\":\"Arian-Band-Panjereh\",\"index\":17},{\"next\":\"Arian-Band-Setareh\",\"index\":18},{\"next\":\"Arian-Band-Ey-Javidan-Iran\",\"index\":19},{\"next\":\"Arian-Band-Tab\",\"index\":20},{\"next\":\"Arian-Band-Gole-Hamishe-Bahar\",\"index\":21},{\"next\":\"Arian-Band-Afsoongar\",\"index\":22},{\"next\":\"Arian-Band-Iran\",\"index\":23},{\"next\":\"Arian-Band-The-Words-I-Love-You-(Feat-Chris-de-Burgh)\",\"index\":24},{\"next\":\"Arian-Band-Bi-To-Ba-To\",\"index\":25},{\"next\":\"Arian-Band-Aroom-Aroom\",\"index\":26},{\"next\":\"Arian-Band-Lahzeh-ha\",\"index\":27},{\"next\":\"Arian-Band-Bahooneh\",\"index\":28},{\"next\":\"Arian-Band-Na-Mehraboon\",\"index\":29},{\"next\":\"Arian-Band-Farda-Male-Mast\",\"index\":30}];\n" + " RJ.nextMp3Base = '/mp3s/mp3/';\n" + " RJ.nextMp3AlbumBase = '/mp3s/album/';\n" + " RJ.playerVolume = 75;\n" + " setupMP3Ping();\n" + "</script>\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