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

/
/
gs

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 = "Track number:(?:.(?!Track number:))*subtitles"; final String string = "+ EBML head\n" + "|+ EBML version: 1\n" + "|+ EBML read version: 1\n" + "|+ EBML maximum ID length: 4\n" + "|+ EBML maximum size length: 8\n" + "|+ Doc type: matroska\n" + "|+ Doc type version: 2\n" + "|+ Doc type read version: 2\n" + "+ Segment, size 467658217\n" + "|+ Seek head (subentries will be skipped)\n" + "|+ EbmlVoid (size: 4029)\n" + "|+ Segment information\n" + "| + Timecode scale: 1000000\n" + "| + Muxing application: libebml v1.0.0 + libmatroska v1.0.0\n" + "| + Writing application: mkvmerge v4.0.0 ('The Stars were mine') built on Jun 6 2010 16:18:42\n" + "| + Duration: 5819.819s (01:36:59.819)\n" + "| + Date: Sat Jul 3 16:19:00 2010 UTC\n" + "| + Segment UID: 0xae 0x0c 0xfb 0x11 0x90 0x39 0x93 0x1b 0x89 0xa4 0xb1 0xaa 0xa0 0x79 0x3d 0x42\n" + "|+ Segment tracks\n" + "| + A track\n" + "| + Track number: 1 (track ID for mkvmerge & mkvextract: 0)\n" + "| + Track UID: 863185562\n" + "| + Track type: video\n" + "| + Default flag: 0\n" + "| + Lacing flag: 0\n" + "| + MinCache: 1\n" + "| + Codec ID: V_MPEG4/ISO/AVC\n" + "| + CodecPrivate, length 41 (h.264 profile: High @L3.1)\n" + "| + Default duration: 41.708ms (23.976 frames/fields per second for a video track)\n" + "| + Language: und\n" + "| + Video track\n" + "| + Pixel width: 1280\n" + "| + Pixel height: 534\n" + "| + Display width: 1280\n" + "| + Display height: 534\n" + "| + A track\n" + "| + Track number: 2 (track ID for mkvmerge & mkvextract: 1)\n" + "| + Track UID: 3319793313\n" + "| + Track type: audio\n" + "| + Default flag: 0\n" + "| + Codec ID: A_AAC\n" + "| + CodecPrivate, length 7\n" + "| + Default duration: 42.667ms (23.438 frames/fields per second for a video track)\n" + "| + Audio track\n" + "| + Sampling frequency: 24000\n" + "| + Channels: 2\n" + "| + Output sampling frequency: 48000\n" + "| + A track\n" + "| + Track number: 3 (track ID for mkvmerge & mkvextract: 2)\n" + "| + Track UID: 1382186431\n" + "| + Track type: subtitles\n" + "| + Lacing flag: 0\n" + "| + Codec ID: S_TEXT/UTF8\n" + "|+ EbmlVoid (size: 1122)\n" + "|+ Chapters\n" + "| + EditionEntry\n" + "| + EditionFlagHidden: 0\n" + "| + EditionFlagDefault: 0\n" + "| + EditionUID: 2614993839\n" + "| + ChapterAtom\n" + "| + ChapterUID: 2912241034\n" + "| + ChapterTimeStart: 00:00:00.097000000\n" + "| + ChapterFlagHidden: 0\n" + "| + ChapterFlagEnabled: 1\n" + "| + ChapterDisplay\n" + "| + ChapterString: 00:00:00.097\n" + "| + ChapterLanguage: eng\n" + "|+ EbmlVoid (size: 101)\n" + "|+ Cluster\n" + "|+ \n" + "| + A track\n" + "| + Track number: 2 (track ID for mkvmerge & mkvextract: 1)\n" + "| + Track UID: 3319793313\n" + "| + Track type: audio\n" + "| + Default flag: 0\n" + "| + Codec ID: A_AAC\n" + "| + CodecPrivate, length 7\n" + "| + Default duration: 42.667ms (23.438 frames/fields per second for a video track)\n" + "| + Audio track\n" + "| + Sampling frequency: 24000\n" + "| + Channels: 2\n" + "| + Output sampling frequency: 48000\n\n\n" + "+ EBML head\n" + "|+ EBML version: 1\n" + "|+ EBML read version: 1\n" + "|+ EBML maximum ID length: 4\n" + "|+ EBML maximum size length: 8\n" + "|+ Doc type: matroska\n" + "|+ Doc type version: 2\n" + "|+ Doc type read version: 2\n" + "+ Segment, size 467658217\n" + "|+ Seek head (subentries will be skipped)\n" + "|+ EbmlVoid (size: 4029)\n" + "|+ Segment information\n" + "| + Timecode scale: 1000000\n" + "| + Muxing application: libebml v1.0.0 + libmatroska v1.0.0\n" + "| + Writing application: mkvmerge v4.0.0 ('The Stars were mine') built on Jun 6 2010 16:18:42\n" + "| + Duration: 5819.819s (01:36:59.819)\n" + "| + Date: Sat Jul 3 16:19:00 2010 UTC\n" + "| + Segment UID: 0xae 0x0c 0xfb 0x11 0x90 0x39 0x93 0x1b 0x89 0xa4 0xb1 0xaa 0xa0 0x79 0x3d 0x42\n" + "|+ Segment tracks\n" + "| + A track\n" + "| + Track number: 1 (track ID for mkvmerge & mkvextract: 0)\n" + "| + Track UID: 863185562\n" + "| + Track type: video\n" + "| + Default flag: 0\n" + "| + Lacing flag: 0\n" + "| + MinCache: 1\n" + "| + Codec ID: V_MPEG4/ISO/AVC\n" + "| + CodecPrivate, length 41 (h.264 profile: High @L3.1)\n" + "| + Default duration: 41.708ms (23.976 frames/fields per second for a video track)\n" + "| + Language: und\n" + "| + Video track\n" + "| + Pixel width: 1280\n" + "| + Pixel height: 534\n" + "| + Display width: 1280\n" + "| + Display height: 534\n" + "| + A track\n" + "| + Track number: 2 (track ID for mkvmerge & mkvextract: 1)\n" + "| + Track UID: 3319793313\n" + "| + Track type: audio\n" + "| + Default flag: 0\n" + "| + Codec ID: A_AAC\n" + "| + CodecPrivate, length 7\n" + "| + Default duration: 42.667ms (23.438 frames/fields per second for a video track)\n" + "| + Audio track\n" + "| + Sampling frequency: 24000\n" + "| + Channels: 2\n" + "| + Output sampling frequency: 48000\n" + "| + A track\n" + "| + Track number: 3 (track ID for mkvmerge & mkvextract: 2)\n" + "| + Track UID: 1382186431\n" + "| + Track type: subtitles\n" + "| + Lacing flag: 0\n" + "| + Codec ID: S_TEXT/UTF8\n" + "|+ EbmlVoid (size: 1122)\n" + "|+ Chapters\n" + "| + EditionEntry\n" + "| + EditionFlagHidden: 0\n" + "| + EditionFlagDefault: 0\n" + "| + EditionUID: 2614993839\n" + "| + ChapterAtom\n" + "| + ChapterUID: 2912241034\n" + "| + ChapterTimeStart: 00:00:00.097000000\n" + "| + ChapterFlagHidden: 0\n" + "| + ChapterFlagEnabled: 1\n" + "| + ChapterDisplay\n" + "| + ChapterString: 00:00:00.097\n" + "| + ChapterLanguage: eng\n" + "|+ EbmlVoid (size: 101)\n" + "|+ Cluster\n" + "|+ \n" + "| + A track\n" + "| + Track number: 2 (track ID for mkvmerge & mkvextract: 1)\n" + "| + Track UID: 3319793313\n" + "| + Track type: audio\n" + "| + Default flag: 0\n" + "| + Codec ID: A_AAC\n" + "| + CodecPrivate, length 7\n" + "| + Default duration: 42.667ms (23.438 frames/fields per second for a video track)\n" + "| + Audio track\n" + "| + Sampling frequency: 24000\n" + "| + Channels: 2\n" + "| + Output sampling frequency: 48000\n\n\n"; final Pattern pattern = Pattern.compile(regex, Pattern.DOTALL); 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