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

/
/
ig

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+TRN\\s+[a-z\\d]+\\s+\\d+\\s+(\\s+\\d+\\s+)\\w+(\\s+\\d{2}\\w{3}\\s+)\\d\\s([a-z]{5})\\s+([a-z]{5})\\s[a-z\\d]+\\s+[\\D]+(\\d{4}|\\d{0})\\s+(\\d{4}|\\d{0})"; final String string = "4 TRN 2C 87 6628 AF 26NOV 4 FRLPD FRPLY HK1 1800 2007 \n" + "3 TRN 2C 87 5266 BI 16NOV 1 FRBOJ FRMLV HK PAST 3333 3333*\n" + "4 TRN 2C 87 5454 BI 19NOV 4 FRMLV FRBOJ HK PAST *\n" + "3 TRN 2C 87 5266 BI 16NOV 1 FRBOJ FRMLV HK PAST *\n" + "4 TRN 2C 87 5454 BI 19NOV 4 FRMLV FRBOJ HK PAST *\n" + "3 TRN 2C 87 6609 AF 23NOV 1 FRPLY FRLPD HK PAST *\n" + "4 TRN 2C 87 6628 AF 26NOV 4 FRLPD FRPLY HK1 1800 2007\n" + "3 TRN 2C 87 6817 AF 25NOV 3 FRLPD FRBZR HK1 1810 2047\n" + " FRLPD/LYON PART DIEU//FRBZR/BEZIERS /TGD *\n" + "4 TRN 2C 87 6860 AF 27NOV 5 FRBZR FRLPD HK1 1618 1850\n" + " FRBZR/BEZIERS//FRLPD/LYON PART DIEU /TGD *\n" + "3 TRN 2C 87 6201 BF 23NOV 1 FRPLY FRVLA HK PAST *\n" + "4 TRN 2C 87 6194 BF 24NOV 2 FRVAF FRPLY HK1 0843 1110\n" + " FRVAF/VALENCE VILLE//FRPLY/PARIS GARE LYON /TGD *\n" + "3 TRN 2C 87 3101 B 24NOV 2 FRPSL FRAEZ HK1 0653 0903\n" + " FRPSL/PARIS ST LAZARE//FRAEZ/LE HAVRE /TIB *\n" + "4 TRN 2C 87 3130 A 25NOV 3 FRAEZ FRPSL HK1 1757 2010\n" + " FRAEZ/LE HAVRE//FRPSL/PARIS ST LAZARE /TIB *\n" + "3 TRN 2C 87 6700 BF 26NOV 4 FRAEK FRPLY HK1 0542 0837\n" + " FRAEK/MULHOUSE VILLE//FRPLY/PARIS GARE LYON /TGD *\n" + "4 TRN 2C 87 9223 BF 27NOV 5 FRPLY FRAEK HK1 1823 2103\n" + " FRPLY/PARIS GARE LYON//FRAEK/MULHOUSE VILLE /TGL *\n" + "3 TRN 2C 87 5352 BF 26NOV 4 FRLPD FRDJU HK1 0629 0835\n" + " FRLPD/LYON PART DIEU//FRDJU/MASSY TGV /TGD *\n" + "4 TRN 2C 87 5233 BF 26NOV 4 FRDJU FRRNS HK1 1538 1747\n" + " FRDJU/MASSY TGV//FRRNS/RENNES /TGA *\n" + "5 TRN 2C 87 5346 BF 27NOV 5 FRRNS FRLPD HK1 1609 2030\n" + " FRRNS/RENNES//FRLPD/LYON PART DIEU /TGD *\n" + "3 TRN 2C 87 6602 BF 30NOV 1 FRLPD FRPLY HK1 0602 0813\n" + " FRLPD/LYON PART DIEU//FRPLY/PARIS GARE LYON /TGD *\n" + "4 TRN 2C 87 6629 BF 04DEC 5 FRPLY FRLPD HK1 1857 2057\n" + " FRPLY/PARIS GARE LYON//FRLPD/LYON PART DIEU /TGD"; final Pattern pattern = Pattern.compile(regex, 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