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

/
/
gmi

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 = "[FHD]?[LP]U?\\d{3}|H032B|RVS8N"; final String string = "BUSS4 Business Flat Line Bundle\n" + "FSULR Ftr Simply Unl LD Bundle\n" + "CC55P Addl Line Basic 2yr Cred n/a Bundle Discount\n" + "FSCC1 Ftr Simply Unl Feat Bundle Discount\n" + "WZC21 LD Discount 24 MO Bundle Discount\n" + "RE099 Additional Line Credit Discount\n" + "RE117 Solutions Bundle Discount Discount\n" + "WZ101 Simply Unlimited Term Discount\n" + "BLSR1 Business Line - Rotary Feature\n" + "CX113 Centranet Feature Package Feature\n" + "IWMB7 Inside Wire Maint - Bus Feature\n" + "OPSN1 Oprtr Call Scrng Inbound Feature\n" + "OVOP4 Onepoint Voice Ma Feature\n" + "VDI03 Unlimited Local Toll n/a Toll\n" + "VDI04 Unlimited Regional toll c n/a Toll\n" + "B1 Business Line \n" + "B1FT3 Business Line - 3 Yr Term \n" + "B1M Business Line - Metered \n" + "CFNT1 CentraNet Stn Ln 2-25 \n" + "CXAM1 CustoPak Ln Measrd Rate \n" + "EUAPB ISDN BRI Interst Acc Port \n" + "FEA1P Addl Line Unl 2 Yr Feat \n" + "IBCD6 ISDN B Channel Voice & Da \n" + "IBRB1 ISDN Single User Access \n" + "ISA06 ISDN BRI Access \n" + "NP Non-Published Listing \n" + "SOLF2 Sol Bun Line 2yr Cpk Feat \n" + "SOLF3 Solutions Feat Pack \n" + "VLC21 Unlimited Local and ZUM c n/a \n" + "WZC70 LEC Discount Bus 24 MO \n\n" + " WZB90 HSI Discount 99 MO Discount\n" + " WZB93 FiOS Internet Bus 99 MO Discount\n" + " WZC66 HSI Discount 24 MO Discount\n" + "MSC03 FiOS Quantum Gateway Rout Equipment\n" + " DL658 High Speed Inet - 7.1/768 \n" + " DP658 High Speed Inet - 7.1/768 \n" + " FL503 FiOSInet 25M/25M 2YR Loop \n" + " FP503 FiOSInet 25M/25M 2YR Port \n" + " H032B FiOS Internet \n" + " HL384 High Speed Inet - 7.1/768 \n" + " HP384 High Speed Inet - 7.1/768 \n" + " LU040 FiOS Internet 25/25 Mb \n" + " PU040 FiOS Internet 25/25 Mb \n" + " RVS8N Online Bkup & Shrng/50GB \n\n" + "VDO03 Unlimited Long Distance n/a\n" + "TTWLD Talk to the World \n" + "VDO04 Unlimited long distance c n/a\n"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE | Pattern.CASE_INSENSITIVE); 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