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

Substitution

Processing...

Code Generator

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(?:C(?:WS|[DS])?T|DT|E[DS]?T|FT|K[DS]T|LMT|M[S]?T|NAS?T|QTT|RT|ST|W[DS]T|Z(?:OS|[OS])?T|oE|T)|B(?:RS|[NORST])T|C(?:AS|ES|H(?:A[DS]|OS|[OU])|ID?S|LS|hS|[ACDEKLOSVX])?T|D(?:AV|DU)T|E(?:ASS?|ES|GS|[ACDEGS])?T|F(?:JS|KS|[EJKN])T|G(?:A[LM]|IL|[EFMSY])T|H(?:OVS?|[DKS])T|I(?:R(?:KS|[DKS])|[CDOS])T|JST|K(?:OS|RAS?|UY|[GS])T|L(?:H[DS]|IN)T|M(?:A(?:GS|[GRW])T|DT|HT|MT|S[DKT]|UT|VT|YT|T)|N(?:FD|OVS?|Z[DS]|[CDFPRSU])T|O(?:MSS?|RA)T|P(?:ETS?|HO|M[DS]|ON|YS|[DEGHKSWY])?T|QYZT|R(?:OT|E)T|S(?:A[KMS]|RE|YO|[BCGRS])T|T(?:AH|OS|[FJKLMORV])T|U(?:LAS?T|TC|YS?T|ZT)|V(?:LAS?|OS|[EU])T|W(?:A(?:RS|[KS])?T|ES?T|FT|GS?T|I(?:TA|[BT])|ST|T)|Y(?:A(?:KS|[KP])|EKS?)T|[ABCDEFGHIKLMNOPQRSTUVWXYZ])$"; final String string = "A\n" + "ACDT\n" + "ACST\n" + "ACT\n" + "ACT\n" + "ACWST\n" + "ADT\n" + "ADT\n" + "AEDT\n" + "AEST\n" + "AET\n" + "AFT\n" + "AKDT\n" + "AKST\n" + "ALMT\n" + "AMST\n" + "AMST\n" + "AMT\n" + "AMT\n" + "ANAST\n" + "ANAT\n" + "AQTT\n" + "ART\n" + "AST\n" + "AST\n" + "AT\n" + "AWDT\n" + "AWST\n" + "AZOST\n" + "AZOT\n" + "AZST\n" + "AZT\n" + "AoE\n" + "B\n" + "BNT\n" + "BOT\n" + "BRST\n" + "BRT\n" + "BST\n" + "BST\n" + "BST\n" + "BTT\n" + "C\n" + "CAST\n" + "CAT\n" + "CCT\n" + "CDT\n" + "CDT\n" + "CEST\n" + "CET\n" + "CHADT\n" + "CHAST\n" + "CHOST\n" + "CHOT\n" + "CHUT\n" + "CIDST\n" + "CIST\n" + "CKT\n" + "CLST\n" + "CLT\n" + "COT\n" + "CST\n" + "CST\n" + "CST\n" + "CT\n" + "CVT\n" + "CXT\n" + "ChST\n" + "D\n" + "DAVT\n" + "DDUT\n" + "E\n" + "EASST\n" + "EAST\n" + "EAT\n" + "ECT\n" + "EDT\n" + "EEST\n" + "EET\n" + "EGST\n" + "EGT\n" + "EST\n" + "ET\n" + "F\n" + "FET\n" + "FJST\n" + "FJT\n" + "FKST\n" + "FKT\n" + "FNT\n" + "G\n" + "GALT\n" + "GAMT\n" + "GET\n" + "GFT\n" + "GILT\n" + "GMT\n" + "GST\n" + "GST\n" + "GYT\n" + "H\n" + "HDT\n" + "HKT\n" + "HOVST\n" + "HOVT\n" + "HST\n" + "I\n" + "ICT\n" + "IDT\n" + "IOT\n" + "IRDT\n" + "IRKST\n" + "IRKT\n" + "IRST\n" + "IST\n" + "IST\n" + "IST\n" + "JST\n" + "K\n" + "KGT\n" + "KOST\n" + "KRAST\n" + "KRAT\n" + "KST\n" + "KUYT\n" + "L\n" + "LHDT\n" + "LHST\n" + "LINT\n" + "M\n" + "MAGST\n" + "MAGT\n" + "MART\n" + "MAWT\n" + "MDT\n" + "MHT\n" + "MMT\n" + "MSD\n" + "MSK\n" + "MST\n" + "MT\n" + "MUT\n" + "MVT\n" + "MYT\n" + "N\n" + "NCT\n" + "NDT\n" + "NFDT\n" + "NFT\n" + "NOVST\n" + "NOVT\n" + "NPT\n" + "NRT\n" + "NST\n" + "NUT\n" + "NZDT\n" + "NZST\n" + "O\n" + "OMSST\n" + "OMST\n" + "ORAT\n" + "P\n" + "PDT\n" + "PET\n" + "PETST\n" + "PETT\n" + "PGT\n" + "PHOT\n" + "PHT\n" + "PKT\n" + "PMDT\n" + "PMST\n" + "PONT\n" + "PST\n" + "PST\n" + "PT\n" + "PWT\n" + "PYST\n" + "PYT\n" + "PYT\n" + "Q\n" + "QYZT\n" + "R\n" + "RET\n" + "ROTT\n" + "S\n" + "SAKT\n" + "SAMT\n" + "SAST\n" + "SBT\n" + "SCT\n" + "SGT\n" + "SRET\n" + "SRT\n" + "SST\n" + "SYOT\n" + "T\n" + "TAHT\n" + "TFT\n" + "TJT\n" + "TKT\n" + "TLT\n" + "TMT\n" + "TOST\n" + "TOT\n" + "TRT\n" + "TVT\n" + "U\n" + "ULAST\n" + "ULAT\n" + "UTC\n" + "UYST\n" + "UYT\n" + "UZT\n" + "V\n" + "VET\n" + "VLAST\n" + "VLAT\n" + "VOST\n" + "VUT\n" + "W\n" + "WAKT\n" + "WARST\n" + "WAST\n" + "WAT\n" + "WEST\n" + "WET\n" + "WFT\n" + "WGST\n" + "WGT\n" + "WIB\n" + "WIT\n" + "WITA\n" + "WST\n" + "WST\n" + "WT\n" + "X\n" + "Y\n" + "YAKST\n" + "YAKT\n" + "YAPT\n" + "YEKST\n" + "YEKT\n" + "Z"; final String subst = "$1"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE); final Matcher matcher = pattern.matcher(string); // The substituted value will be contained in the result variable final String result = matcher.replaceAll(subst); System.out.println("Substitution result: " + result); } }

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