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 = "(\\d{2})\\/(\\d{2})\\/(\\d{2})\\s+(\\d{2}):(\\d{2})\\s+([\\d]+)\\s+([\\d]+|)\\s+(<I>|)(EXT|)([\\w]+|)(\\s+|)((\\d{1})'(\\d{2})|)(\\s+|)((\\d{2}):(\\d{2})'(\\d{2})\\s+(.*) |)"; final String string = "01/02/16 09:37 1142 01 2286542PPPPPP9131874263 00:00'24 \n" + "01/02/16 09:37 1204 48 2181 00:01'33 \n" + "01/02/16 09:37 1221 33 <I>3342 0'00 00:01'25 TR \n" + "01/02/16 09:38 1232 02 2286542PPPPPP9082035024 00:00'12 \n" + "01/02/16 09:39 1711 EXT1132 \n" + "01/02/16 09:39 1232 01 2286542PPPPPP9082035024 00:00'02 \n" + "01/02/16 09:39 5910 11 <I> 0'01 00:00'37 D0 \n" + "01/02/16 09:39 1602 EXT1611 \n" + "01/02/16 09:39 1332 EXT1204 \n" + "01/02/16 09:40 1222 34 <I>3933 0'02 00:00'14 \n" + "01/02/16 09:40 1232 EXT1393 \n" + "01/02/16 09:41 1262 EXT1154 \n" + "03/02/16 16:11 2181 EXT2421 \n" + "03/02/16 16:13 2181 05 89509600795 00:00'47 \n" + "03/02/16 16:13 2314 24 1242 00:00'08 \n" + "03/02/16 15:07 2162 05 <I> 0'00 00:00'15 TR \n" + "03/02/16 15:09 2004 05 <I> 0'05 00:00'50 \n" + "03/02/16 15:11 2004 05 <I> 0'38 00:00'00 NA \n" + "03/02/16 15:12 2004 06 <I> 0'11 00:00'26 \n" + "03/02/16 15:16 2004 05 <I> 0'04 00:01'02 \n" + "03/02/16 15:18 2181 17 <I>1396 0'04 00:12'23 \n" + "03/02/16 15:20 2151 07 89020100016 00:00'17 \n" + "03/02/16 15:21 2004 24 1132 00:00'24 TR \n" + "03/02/16 15:21 2004 05 <I> 0'05 00:01'37 \n" + "03/02/16 15:21 2151 07 89509668727 00:00'22 \n" + "03/02/16 15:23 2151 05 89020116661 00:00'20 \n" + "01/02/16 09:31 5910 11 <I> 0'01 00:00'24 D0 \n" + "01/02/16 09:31 1221 33 <I>4351 0'00 00:04'55 TR \n" + "01/02/16 09:31 5910 03 <I>89831514875 0'01 00:00'14 D0 \n" + "01/02/16 09:32 1204 11 <I> 0'00 00:00'45 TR \n" + "01/02/16 09:32 1125 03 <I>89831514875 0'00 00:00'16 TR \n" + "01/02/16 09:32 5910 03 <I>89831514875 0'01 00:00'13 D0 \n" + "01/02/16 09:32 5910 09 <I> 0'01 00:00'10 D0 "; 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