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 = "(\\d{2}\\/\\d{2}\\/\\d{4}),\\s(\\d(?:\\d)?:\\d{2})\\s-\\s([^:]*):\\s(.*?)(?=\\s*\\d{2}\\/|$)"; final String string = " 09/05/2016, 13:11 - Joe Bloggs: Hey Jane how're you doing? ? what dates are you in London again? I realise that June isn't actually that far away so might book my trains down sooner than later!\n" + "09/05/2016, 13:47 - Jane Doe: Hey! I'm in london from the 12th-16th of june! Hope you can make it down :) sorry it's a bit annoying i couldn't make it there til a sunday!\n" + "09/05/2016, 14:03 - Joe Bloggs: Right I'll speak to my boss! I've just requested 5 weeks off in November/December to visit Aus so I'll see if I can negotiate some other days!\n\n" + "When does your uni term end in November? I'm thinking of visiting perth first then going to the east coast!\n" + "09/05/2016, 22:32 - Jane Doe: Oh that'll be awesome if you come to aus! Totally understand if it's too hard for you to request more days off in june. \n\n" + "I finish uni early November! So should definitely be done by then if you came here\n" + "09/05/2016, 23:20 - Joe Bloggs: I could maybe get a couple of days ? when do you fly into London on the Sunday?\n\n" + "Perfect! I need to speak to everyone else to make sure they're about. I can't wait to visit but it's so far away!\n" + "09/05/2016, 23:30 - Jane Doe: I fly in at like 7.30am so I'll have that whole day!\n\n" + "I'm sure the year will fly since it's may already haha\n" + "09/05/2016, 23:34 - Joe Bloggs: Aw nice one! Even if I can get just Monday off I can get an early train on Sunday ?\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