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 = "(?xim)\n" + "^\\s*\n" + "(?<Num1>\\d+)\n" + "\\s+\n" + "(?<Dots>.*?)\n" + "\\s+\n" + "(?<X>.*?)\n" + "\\s+\n" + "(?<ExtList>.*?)\n" + "\\s{2,}\n" + "(?<Rest>.*)\n" + "$\n\n" + "# //\n" + "# (?<ExtList>.*)\n" + "# \\s{2,}\n" + "# (?<BytesOr>(\\|.{2}))*?\n" + "#$"; final String string = "7z -i\n" + "7-Zip 22.00 (x64) : Copyright (c) 1999-2022 Igor Pavlov : 2022-06-15\n" + "Libs:\n" + " 0 c:\\program files\\7-zip\\7z.dll\n\n" + "Formats:\n" + " 0 C...F..........c.a.m+.. w...0 7z 7z 7 z BC AF ' 1C\n" + " 0 ...................... APFS apfs img offset=32 N X S B 00\n" + " 0 ...................... APM apm E R\n" + " 0 ...................... Ar ar a deb udeb lib ! < a r c h > 0A\n" + " 0 ...................... Arj arj ` EA\n" + " 0 K.....O.....X......... Base64 b64 \n" + " 0 ......O............... COFF obj \n" + " 0 ...F.................. Cab cab M S C F 00 00 00 00\n" + " 0 ...................... Chm chm chi chq chw I T S F 03 00 00 00 ` 00 00 00\n" + " 0 ...................... Compound msi msp doc xls ppt D0 CF 11 E0 A1 B1 1A E1\n" + " 0 ....M................. Cpio cpio 0 7 0 7 0 || C7 q || q C7\n" + " 0 ...................... CramFS cramfs offset=16 C o m p r e s s e d 20 R O M F S\n" + " 0 .....G..B............. Dmg dmg k o l y 00 00 00 04 00 00 02 00\n" + " 0 .........E............ ELF elf  E L F\n" + " 0 ...................... Ext ext ext2 ext3 ext4 img offset=1080 S EF\n" + " 0 ...................... FAT fat img offset=510 U AA\n" + " 0 ...................... FLV flv F L V 01\n" + " 0 ...................... GPT gpt mbr offset=512 E F I 20 P A R T 00 00 01 00\n" + " 0 ....M................. HFS hfs hfsx offset=1024 B D || H + 00 04 || H X 00 05\n" + " 0 ...F.................. Hxs hxs hxi hxr hxq hxw lit I T O L I T L S 01 00 00 00 ( 00 00 00\n" + " 0 ......O............... IHex ihex \n" + " 0 ...................... Iso iso img offset=32769 C D 0 0 1\n" + " 0 ...................... LP lpimg img offset=4096 g D l a 4 00 00 00\n" + " 0 ...................... Lzh lzh lha offset=2 - l h\n" + " 0 .......P.............. MBR mbr \n" + " 0 ....M....E............ MachO macho CE FA ED FE || CF FA ED FE || FE ED FA CE || FE ED FA CF\n" + " 0 ...................... MsLZ mslz S Z D D 88 F0 ' 3 A\n" + " 0 ....M................. Mub mub CA FE BA BE 00 00 00 || B9 FA F1 0E\n" + " 0 ...................... NTFS ntfs img offset=3 N T F S 20 20 20 20 00\n" + " 0 ...F.G................ Nsis nsis offset=4 EF BE AD DE N u l l s o f t I n s t\n" + " 0 .........E............ PE exe dll sys M Z\n" + " 0 ...................... Ppmd pmd 8F AF AC 84\n" + " 0 ...................... QCOW qcow qcow2 qcow2c Q F I FB 00 00 00\n" + " 0 ...F.................. Rar rar r00 R a r ! 1A 07 00\n" + " 0 ...F.................. Rar5 rar r00 R a r ! 1A 07 01 00\n" + " 0 ...................... Rpm rpm ED AB EE DB\n" + " 0 K..................... SWF swf F W S\n" + " 0 ....M................. SWFc swf (~.swf) C W S || Z W S\n" + " 0 ...................... Sparse simg img : FF & ED 01 00\n" + " 0 ...................... Split 001 \n" + " 0 ....M................. SquashFS squashfs h s q s || s q s h || s h s q || q s h s\n" + " 0 .........E............ TE te V Z\n" + " 0 ...FM................. UEFIc scap BD 86 f ; v 0D 0 @ B7 0E B5 Q 9E / C5 A0 || 8B A6 < J # w FB H 80 = W 8C C1 FE C4 M || B9 82 91 S B5 AB 91 C B6 9A E3 A9 C F7 / CC\n" + " 0 ...FM................. UEFIf uefif offset=16 D9 T 93 z h 04 J D 81 CE 0B F6 17 D8 90 DF || x E5 8C 8C = 8A 1C O 99 5 89 a 85 C3 - D3\n" + " 0 ......O............... Udf udf iso img offset=32768 01 C D 0 0 1\n" + " 0 ...................... VDI vdi offset=64  10 DA BE\n" + " 0 .....G................ VHD vhd c o n e c t i x 00 00\n" + " 0 ...................... VHDX vhdx avhdx v h d x f i l e\n" + " 0 ...................... VMDK vmdk K D M V\n" + " 0 ...................... Xar xar pkg xip x a r ! 00 1C\n" + " 0 ...................... Z z taz (.tar) 1F 9D\n" + " 0 CK..................... bzip2 bz2 bzip2 tbz2 (.tar) tbz (.tar) B Z h\n" + " 0 CK.................m+.. .u..1 gzip gz gzip tgz (.tar) tpz (.tar) apk (.tar) 1F 8B 08\n" + " 0 K.....O............... lzma lzma \n" + " 0 K..................... lzma86 lzma86 \n" + " 0 C......O...LH......m+.. wu.n1 tar tar ova offset=257 u s t a r\n" + " 0 C.SN.......LH..c.a.m+.. w...0 wim wim swm esd ppkg M S W I M 00 00 00\n" + " 0 CK..................... xz xz txz (.tar) FD 7 z X Z 00\n" + " 0 C...FMG........c.a.m+.. wud.0 zip zip z01 zipx jar xpi odt ods docx xlsx epub ipa apk appx P K 03 04 || P K 05 06 || P K 06 06 || P K 07 08 P K || P K 0 0 P K\n" + " CK.....O.....XC........ Hash sha256 sha512 sha224 sha384 sha1 sha md5 crc32 crc64 asc cksum \n\n" + "Codecs:\n" + " 0 4ED 303011B BCJ2\n" + " 0 EDF 3030103 BCJ\n" + " 0 EDF 3030205 PPC\n" + " 0 EDF 3030401 IA64\n" + " 0 EDF 3030501 ARM\n" + " 0 EDF 3030701 ARMT\n" + " 0 EDF 3030805 SPARC\n" + " 0 EDF 20302 Swap2\n" + " 0 EDF 20304 Swap4\n" + " 0 ED 40202 BZip2\n" + " 0 ED 0 Copy\n" + " 0 ED 40109 Deflate64\n" + " 0 ED 40108 Deflate\n" + " 0 EDF 3 Delta\n" + " 0 ED 21 LZMA2\n" + " 0 ED 30101 LZMA\n" + " 0 ED 30401 PPMD\n" + " 0 D 40301 Rar1\n" + " 0 D 40302 Rar2\n" + " 0 D 40303 Rar3\n" + " 0 D 40305 Rar5\n" + " 0 EDF 6F10701 7zAES\n" + " 0 EDF 6F00181 AES256CBC\n\n" + "Hashers:\n" + " 0 4 1 CRC32\n" + " 0 20 201 SHA1\n" + " 0 32 A SHA256\n" + " 0 8 4 CRC64\n" + " 0 32 202 BLAKE2sp"; 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