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 = "(?<=\\bdestination\\s\\/\\S+\\/\\d{1,3}\\.\\d{1,3}\\.\\d{1,3}\\.\\d{1,3}:)(?:2[89][0-9]{3}|3[01][0-9]{3}|32[0-6][0-9]{2}|327[0-5][0-9]|6[5-9][0-9]{3}|65[0-4][0-9]{2}|6553[0-5]|(?:22|53|68|323|500|1067|2379|2380|4500|5355|6443|8005|8007|8087|8443|8444|8505|8507|9007|9090|9153|9999|10249|10250|10251|10252|10256|10257|10259|18091|18092|18093|18095|22222|23790|23791|23801|23802))"; final String string = "\n" + "ltm virtual /Common/byoadc-VIP {\n" + " description mylistener.byoadc.com\n" + " destination /Common/157.109.110.76:28010\n" + " ip-protocol tcp\n" + " last-modified-time 2023-04-15:13:23:53\n" + " mask 255.255.255.255\n" + " pool /Common/SSLSUPPORT-POOL\n" + " profiles {\n" + " /Common/byoadc_2024 {\n" + " context clientside\n" + " }\n" + " /Common/http { }\n" + " /Common/tcp { }\n" + " }\n\n" + "ltm virtual /Microsoft-Exchange/pool-int-dns-tcp-53 {\n" + " destination /Microsoft-Exchange/10.175.99.145:53\n" + " ip-protocol tcp\n" + " mask 255.255.255.255\n" + " pool /Microsoft-Exchange/pool-int-dns-53\n" + " profiles {\n" + " /Common/tcp { }\n" + " }\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