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

/
/
gmx

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 = "(?:\n" + " ^\n" + " \\s*\n" + " (?<host>[\\w-\\.]*)\n" + " \\s*\n" + " (?<rectype>\\w*)\n" + " \\s*\n" + " (?<value>[\\w\\.-].*)\n" + " \\s*$\n" + ")"; final String string = "> ls -d midlandls.pncint.net \n" + "[pasum60ad02.pncint.net]\n" + " midlandls.pncint.net. SOA vasan60ad03.pncint.net ip.address.request.pncbank.com. (562550790 10800 3600 1209600 60)\n" + " midlandls.pncint.net. NS vaash60ad04.pncint.net \n" + " midlandls.pncint.net. NS pasum60ad11.pncint.net \n" + " midlandls.pncint.net. NS pasum60ad01.pncint.net \n" + " midlandls.pncint.net. NS pasum60ad02.pncint.net \n" + " arcs-msmq CNAME weka357w.prod.pncint.net\n" + " bar-rpt CNAME wbar303a.prod.pncint.net\n" + " Bin CNAME services-gf2.midlandls.pncint.net\n" + " cigna-msmq CNAME welm350w.prod.pncint.net\n" + " citigroup-msmq CNAME welm352w.prod.pncint.net\n" + " Cwm CNAME services-gf2.midlandls.pncint.net\n" + " Cwm-app CNAME services-gf2.midlandls.pncint.net\n" + " cwm-rpt CNAME wcwm316a.prod.pncint.net\n" + " dbank-msmq CNAME welm344w.prod.pncint.net\n" + " egs CNAME egs-gf0.midlandls.pncint.net\n" + " egs-gf0 A 10.15.5.238\n" + " egs-gf1 A 10.38.5.238\n" + " egs-snat-gf0 A 10.15.7.238\n" + " egs-snat-gf1 A 10.38.7.238\n" + " eka CNAME services-gf2.midlandls.pncint.net\n" + " elm CNAME services-gf2.midlandls.pncint.net\n" + " fdic-msmq CNAME welm358w.prod.pncint.net\n" + " genworth-msmq CNAME welm365w.prod.pncint.net\n" + " icsg-msmq CNAME welm375w.prod.pncint.net\n" + " iru CNAME services-gf2.midlandls.pncint.net\n" + " iru-rpt CNAME wiru307a.prod.pncint.net\n" + " mat CNAME services-gf2.midlandls.pncint.net\n" + " mat-app CNAME services-gf2.midlandls.pncint.net\n" + " mat-rpt CNAME wmat302a.prod.pncint.net\n" + " mde CNAME services-gf2.midlandls.pncint.net\n" + " mde-internet CNAME services-gf2.midlandls.pncint.net\n" + " mfn CNAME services-gf2.midlandls.pncint.net\n" + " mfn-app CNAME services-gf2.midlandls.pncint.net\n" + " mfn-rpt CNAME wmfn318a.prod.pncint.net\n" + " mis CNAME services-gf2.midlandls.pncint.net\n" + " mis-app CNAME services-gf2.midlandls.pncint.net\n" + " mis-rpt CNAME wmis308a.prod.pncint.net\n" + " mls-msmq CNAME weka353w.prod.pncint.net\n" + " mvm CNAME services-gf1.midlandls.pncint.net\n" + " mvm-rpt CNAME wmvm302a.prod.pncint.net\n" + " pii CNAME services-gf2.midlandls.pncint.net\n" + " pnc-msmq CNAME weka373w.prod.pncint.net\n" + " pnclms-msmq CNAME weka349w.prod.pncint.net\n" + " rdt CNAME services-gf1.midlandls.pncint.net\n" + " services-gf1 A 10.26.64.229\n" + " services-gf2 A 10.28.8.229\n" + " services-snat-gf1 A 10.26.68.249\n" + " services-snat-gf2 A 10.28.12.227\n" + " wdunlop-msmq CNAME welm31bw.prod.pncint.net\n" + " wlm CNAME services-gf2.midlandls.pncint.net\n" + " wlm-app CNAME wwlm305w.prod.pncint.net\n" + " wlm-rpt CNAME wwlm306a.prod.pncint.net\n" + " midlandls.pncint.net. SOA vasan60ad03.pncint.net ip.address.request.pncbank.com. (562550790 10800 3600 1209600 60)\n"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE | Pattern.COMMENTS); 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