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

Substitution

Processing...

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 = "(?<level>\\d+)\\s*(?<wood>\\d+)\\s*(?<clay>\\d+)\\s*(?<iron>\\d+)\\s*(?<crop>\\d+)\\s*(?<cropusage>\\d+)\\s*(?<time>\\d+:\\d+:\\d+)\\s*(?<pop>\\d+)\\s*(?<production>\\d+)"; final String string = "1 70 90 70 20 0 00:02:30 1 7\n" + "2 115 150 115 35 0 00:07:20 1 13\n" + "3 195 250 195 55 0 00:15:00 2 21\n" + "4 325 420 325 95 0 00:27:30 2 31\n" + "5 545 700 545 155 0 00:47:10 2 46\n" + "6 910 1170 910 260 1 01:18:50 3 70\n" + "7 1520 1950 1520 435 1 02:03:40 4 98\n" + "8 2535 3260 2535 725 1 03:30:40 4 140\n" + "9 4235 5445 4235 1210 1 05:40:30 5 203\n" + "10 7070 9095 7070 2020 1 09:08:00 6 280\n" + "11 11810 15185 11810 3375 1 14:40:10 7 392\n" + "12 19725 25360 19725 5635 1 23:31:40 9 525\n" + "13 32940 42350 32940 9410 1 37:41:50 11 693\n" + "14 55005 70720 55005 15715 1 60:22:20 13 889\n" + "15 91860 118105 91860 26245 1 96:39:10 15 1120\n" + "16 153405 197240 153405 43830 2 154:41:50 18 1400\n" + "17 256190 329385 256190 73195 2 247:34:20 22 1820\n" + "18 427835 550075 427835 122240 2 396:10:10 27 2240\n" + "19 714485 918625 714485 204140 2 633:550: 32 2800\n" + "20\n" + " 1193195 1534105 1193195 340915 2 1014:20:30 38 3430"; final String subst = "<Level val=\"${level}\"><Resources><Wood>${wood}</Wood><Clay>${clay}</Clay><Iron>${iron}</Iron><Crop>${crop}</Crop><CropUsage>${cropusage}</CropUsage></Resources><UpgradeTime>${time}</UpgradeTime><Population>${pop}</Population><Production>${production}</Production></Level>"; final Pattern pattern = Pattern.compile(regex); final Matcher matcher = pattern.matcher(string); // The substituted value will be contained in the result variable final String result = matcher.replaceAll(subst); System.out.println("Substitution result: " + result); } }

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