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 = "(?<Servername>[\\w. ()]+)=#(?<Type>\\d+)#0%(?<IP>[\\w.]+)%(?<port>\\d+)%%%([\\w.-]+)%([\\d-]+)%%%([\\w.-]+)%%\\d%([\\w.-]+)%([\\w.-]+)%%%([\\w.-]+)%([\\w.-]+)%([\\w.-]+)%([\\w.-]+)%%\\d+%%\\d%\\d%\\d#"; final String string = "1.2.3.47=#109#0%1.2.3.47%22%%%-1%-1%%%22%%0%-1%0%%%-1%0%0%0%%1080%%0%0%1#MobaFont%10%0%0%0%15%236,236,236%0,0,0%180,180,192%0%-1%0%%xterm%-1%0%0,0,0%54,54,54%255,96,96%255,128,128%96,255,96%128,255,128%255,255,54%255,255,128%96,96,255%128,128,255%255,54,255%255,128,255%54,255,255%128,255,255%236,236,236%255,255,255%80%24%0%1%-1%<none>%%0#0# #-1\n" + " \"10.11.12.13=#109#0%10.11.12.13%6379%%%-1%-1%%%22%%0%-1%0%%%-1%0%0%0%%1080%%0%0%1#MobaFont%10%0%0%0%15%236,236,236%0,0,0%180,180,192%0%-1%0%%xterm%-1%0%0,0,0%54,54,54%255,96,96%255,128,128%96,255,96%128,255,128%255,255,54%255,255,128%96,96,255%128,128,255%255,54,255%255,128,255%54,255,255%128,255,255%236,236,236%255,255,255%80%24%0%1%-1%<none>%%0#0# #-1\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