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 = "^([^\\s]+)(\\s\\d?)(.*)$"; final String string = "CH4 ENGLAND\n" + "CH4 GB\n" + "CH4 LONDON\n" + "CH4 LONDON/SOUTH\n" + "CH4 LONDON/SOUTH/MIDLANDS\n" + "CH4 MIDLANDS\n" + "CH4 NETWORK\n" + "CH4 NORTH\n" + "CH4 SCOTLAND\n" + "CH4 SOUTH\n" + "CH4 ULSTER\n" + "CH4+1 ENGLAND\n" + "CH4+1 GB\n" + "CH4+1 LONDON\n" + "CH4+1 LONDON/SOUTH\n" + "CH4+1 LONDON/SOUTH/MIDLANDS\n" + "CH4+1 MIDLANDS\n" + "CH4+1 NETWORK\n" + "CH4+1 NORTH\n" + "CH4+1 SCOTLAND\n" + "CH4+1 SOUTH\n" + "CH4+1 ULSTER\n" + "CHANNEL 5 NETWORK\n" + "CHANNEL 5+1 NETWORK\n" + "ITV ANGLIA\n" + "ITV BORDER\n" + "ITV BREAKFAST\n" + "ITV BREAKFAST CENTRAL\n" + "ITV BREAKFAST ENG & WALES\n" + "ITV BREAKFAST GREAT BRITAIN\n" + "ITV BREAKFAST HD - ULSTER\n" + "ITV BREAKFAST HD CENTRAL\n" + "ITV BREAKFAST HD ENG & WALES\n" + "ITV BREAKFAST HD GB\n" + "ITV BREAKFAST HD LITTLEBRITAIN\n" + "ITV BREAKFAST HD LONDON\n" + "ITV BREAKFAST HD NETWORK\n" + "ITV BREAKFAST HD NORTH\n" + "ITV BREAKFAST HD SCOTLAND\n" + "ITV BREAKFAST HD SOUTH\n" + "ITV BREAKFAST LITTLEBRITAIN\n" + "ITV BREAKFAST LONDON\n" + "ITV BREAKFAST NORTH\n" + "ITV BREAKFAST SCOTLAND\n" + "ITV BREAKFAST SOUTH\n" + "ITV BREAKFAST ULSTER\n" + "ITV BREAKFAST+1 - ENG & WAL\n" + "ITV BREAKFAST+1 - GB\n" + "ITV BREAKFAST+1 - LONDON\n" + "ITV BREAKFAST+1 - MIDLANDS\n" + "ITV BREAKFAST+1 - NETWORK\n" + "ITV BREAKFAST+1 - NORTH\n" + "ITV BREAKFAST+1 - NTH/STH/MID\n" + "ITV BREAKFAST+1 - SCOTLAND\n" + "ITV BREAKFAST+1 - SOUTH\n" + "ITV BREAKFAST+1 - ULSTER\n" + "ITV CENTRAL\n" + "ITV GRANADA\n" + "ITV GRANADA BORDER MACRO\n" + "ITV HD ANGLIA\n" + "ITV HD BORDER\n" + "ITV HD CENTRAL\n" + "ITV HD GRANADA\n" + "ITV HD GRANADA BORDER MACRO\n" + "ITV HD LONDON CARLTON\n" + "ITV HD LONDON LWT\n" + "ITV HD MERIDIAN\n" + "ITV HD MIDWEST MACRO\n" + "ITV HD NORTH MACRO\n" + "ITV HD SOUTH EAST MACRO\n" + "ITV HD STV MACRO\n" + "ITV HD TYNE TEES\n" + "ITV HD UTV\n" + "ITV HD WALES\n" + "ITV HD WEST\n" + "ITV HD WESTCOUNTRY\n" + "ITV HD YORKSHIRE\n" + "ITV HD YORKSHIRE/TT MACRO\n" + "ITV LONDON CARLTON\n" + "ITV LONDON LWT\n" + "ITV MERIDIAN\n" + "ITV MIDWEST MACRO\n" + "ITV NORTH MACRO\n" + "ITV SOUTH EAST MACRO\n" + "ITV STV MACRO\n" + "ITV TYNE TEES\n" + "ITV UTV\n" + "ITV WALES\n" + "ITV WALES & WEST\n" + "ITV WEST\n" + "ITV WEST MACRO\n" + "ITV WESTCOUNTRY\n" + "ITV YORKSHIRE\n" + "ITV YORKSHIRE TYNE TEES MACRO\n" + "ITV+1- ANGLIA\n" + "ITV+1 - CARLTON\n" + "ITV+1 - CENTRAL\n" + "ITV+1 - GRANADA/BORDER MACRO\n" + "ITV+1 - LWT\n" + "ITV+1 - MERIDIAN\n" + "ITV+1 - MIDWEST MACRO\n" + "ITV+1 - NORTH MACRO\n" + "ITV+1 - SCOTLAND MACRO\n" + "ITV+1 - SOUTH EAST MACRO\n" + "ITV+1 - TYNE TEES\n" + "ITV+1 - ULSTER\n" + "ITV+1 - WALES\n" + "ITV+1 - WALES + WEST MACRO\n" + "ITV+1 - WEST\n" + "ITV+1 - WEST MACRO\n" + "ITV+1 - WESTCOUNTRY\n" + "ITV+1 - YORKSHIRE\n" + "ITV+1 - YORKSHIRE/TT MACRO\n" + "S4C UK\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