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

/
/
g

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 = "^(((([A-Z]+-)?((\\d{2})([A-Z]{3})(\\d{2}))?([A-Z]{3})?( )?((.[0-9A-Z]{3})|([0-9A-Z]{2}))( )([X][\\/])?((E\\/)|(B\\/)|(T\\/)|(L\\/))*(([A-Z][\\/-])?[A-Z]{3})?(?!\\d{1,3}[A-Z\\s])( )?(((E\\/XXX)?|([Q]{1}(( )?([A-Z]{3})([A-Z]{3}))?(\\d+M)?(\\d{1,6}(\\.\\d{1,4})?))?|(M( )?([A-Z]{6})?( )?(\\d{1,6}(\\.\\d{1,4})?)?)?|([R]{1}(\\d+M)?(\\d{1,6}(\\.\\d{1,4})?))?|(([0-9])*S(\\d+M)?(\\d{1,6}(\\.\\d{1,4})?))?|(M?\\/(IT))|(M?\\/(BT))|(\\/\\/([A-Z]{3})))( )?)*(\\d+M( )?)?((?![0-9][A-Z])\\d{1,6}(\\.\\d{1,4})?( )?)?((?<=[0-9])((?![A-Z][A-Z0-9]( )([A-Z]\\/)?[A-Z]{3}|NUC|END|[A-Z]{3}( )[0-9])|(?=[A-Z][A-Z0-9]( )NUC))[A-Z][A-Z0-9\\/]{0,8})?(( )?(([Q]{1}(\\d+M)?(\\d{1,6}(\\.\\d{1,4})?))|(P R\\/([A-Z]{3})(\\/)?([A-Z]{3})?( )?(\\d+M)?(\\d{1,6}(\\.\\d{1,4})?))|(P( )([A-Z]{6})( )?([A-Z]{6})?( )?(\\d+M)?(\\d{1,6}(\\.\\d{1,4})?))|(M( )?([A-Z]{6})?( )?(\\d{1,6}(\\.\\d{1,4})?)?)|(H( )([A-Z]{6})( )?(\\d{1,6}(\\.\\d{1,4})?))|(U( )(( )?([A-Z]{6}))+( )?(\\d{1,6}(\\.\\d{1,4})?))|(C\\/([A-Z]{3})(( )?[A-Z]{6})*( )?(\\d{1,6}(\\.\\d{1,4})?))|(D( )((([A-Z])+\\/)?([A-Z]{6})( )?((M)|(\\d+M)|( )|(\\d{1,6}(\\.\\d{1,4})?))( )?)+)|(\\/-([A-Z]{3}))|(\\/\\/([A-Z]{3})))?( )?)*)+)+)( )?((( )?([A-Z]{3})( )?(\\d{1,6}(\\.\\d{1,4})?))( )?(END)|(END))( )?(ROE( )?\\d+(\\.\\d+)?)?(.*)?$"; final String string = "SIN UB X/RGN101.29ESGR UB NYT110.00YOW UB RGN110.00YOW RGN UB SIN 101"; final Pattern pattern = Pattern.compile(regex); 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