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

/
/
xgJm

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 = "(?'char'[A-F0-9]{4,7})\\;(?'replace'.*)(?:\\s{1}(?'replace'[A-F0-9]{4,7}))+(?=\\s)+(?:\\s{1}(?'replace'[A-F0-9]{4,7}))+(?=\\s)+(?:\\s{1}(?'replace'[A-F0-9]{4,7}))+\\;\\ (?'comment'.*)(?:\\n)|\n" + "(?'char'[A-F0-9]{4,7})\\;(?'replace'.*)(?:\\s{1}(?'replace'[A-F0-9]{4,7}))+(?=\\s)+(?:\\s{1}(?'replace'[A-F0-9]{4,7}))+\\;\\ (?'comment'.*)(?:\\n)|\n" + "(?'char'[A-F0-9]{4,7})\\;(?:\\s{1}(?'replace'[A-F0-9]{4,7}))+(?=\\s)+(?:\\s{1}(?'replace'[A-F0-9]{4,7}))+\\;\\ (?'comment'.*)(?:\\n)|\n" + "(?'char'[A-F0-9]{4,7})\\;(?'replace'.*)\\;\\ (?'comment'.*)(?:\\n)|\n" + "(?'range_start'[A-F0-9]{4,7})\\-(?'range_end'[A-F0-9]{4,7})(?:\\;\\ )(?'comment'.*)(?:\\n)|\n" + "(?'char'[A-F0-9]{4,7})(?:\\;\\ )(?'comment'.*)(?:\\n)|\n" + "(?'range_start'[A-F0-9]{4,7})\\-(?'range_end'[A-F0-9]{4,7})(?:\\n)|\n" + "(?:^\\ {3})(?'char'[A-F0-9]{4,7})(?:\\n)|\n" + "(?<appendix>(?'appendix_type'Start|End)\\sTable\\s(?'appendix_number'(\\w).(?'appendix_order'(\\d)))(?=\\ -----\\n))"; final String string = " F001-AB12\n" + " 0221\n" + " 0234-024F\n" + " 02AE-02AF\n" + " 03AB; 03CB; Case map\n" + " 03B0; 03C5 0308 0301; Case map\n" + " 03C2; 03C3; Case map\n" + " 03B0; 03C5 0308 0301 0A1B; Case map\n" + " ----- Start Table A.1 -----\n" + " 03D0; 03B2; Case map\n" + " 03D1; 03B8; Case map\n" + " ----- End Table A.1 -----\n" + " 03D2; 03C5; Additional folding\n" + " 03D3; 03CD; Additional folding\n" + " 00DF; 0073 0073; Case map\n" + " 037B-037D\n" + " 037F-0383\n" + " 038B\n" + "Hoffman & Blanchet Standards Track [Page 89]\n" + " \n" + "RFC 3454 Preparation of Internationalized Strings December 2002\n" + " 1806; ; Map to nothing\n" + " 1806; ; Map to nothing\n" + " 1806; ; Map to nothing\n" + " 1806; ; Map to nothing\n" + " F0000-FFFFD\n" + " 100000-10FFFD\n" + " F0000\n" + " 013B; 013C; Case map\n" + " 013D; 013E; Case map\n" + " 0080-009F; [CONTROL CHARACTERS]\n" + " 06DD; ARABIC END OF AYAH\n" + " 070F; SYRIAC ABBREVIATION MARK\n" + " 180E; MONGOLIAN VOWEL SEPARATOR\n" + " 200C; ZERO WIDTH NON-JOINER\n" + " 200D; ZERO WIDTH JOINER\n" + " 2028; LINE SEPARATOR\n" + " 2029; PARAGRAPH SEPARATOR\n" + " 2060; WORD JOINER\n" + " 2061; FUNCTION APPLICATION\n" + " 2062; INVISIBLE TIMES\n" + " 013F; 0140; Case map\n" + " 0141; 0142; Case map\n" + " 0143; 0144; Case map\n" + " 0145; 0146; Case map\n" + " 0147; 0148; Case map\n" + " 0149; 02BC 006E; Case map\n" + " 014A; 014B; Case map\n" + " 014C; 014D; Case map\n"; final Pattern pattern = Pattern.compile(regex, Pattern.COMMENTS | 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