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 = "((ltm virtual) ([a-zA-Z0-9_-]*) \\{(.|\\n)*?\\})"; final String string = "Some Garbage text\n" + "ltm virtual The_Name_51244_sdfasfdasd {\n" + " address-status yes\n" + " enabled\n" + " fallback-persistence none\n" + " profiles {\n" + " /Common/GLOBAL_PROFILE {\n" + " context all\n" + " }\n" + " /Common/http {\n" + " context all\n" + " }\n" + " }\n" + " rate-class none\n" + " rules {\n" + " /Common/X-F-F\n" + " }\n" + " log-profiles none\n" + " source-address-translation {\n" + " pool SOME-SNAT-POOL\n" + " type snat\n" + " }\n" + " source-port preserve\n" + " vlans {\n" + " Vlan1111\n" + " }\n" + " service-down-immediate-action none\n" + " service-policy none\n" + " source 0.0.0.0/0\n" + "}\n" + "barbage text\n" + "ltm virtual The_Object_51244 {\n" + " address-status yes\n" + " enabled\n" + " fallback-persistence none\n" + " profiles {\n" + " /Common/GLOBAL_PROFILE {\n" + " context all\n" + " }\n" + " /Common/http {\n" + " context all\n" + " }\n" + " }\n" + " rate-class none\n" + " rules {\n" + " /Common/X-F-F\n" + " }\n" + " log-profiles none\n" + " source-address-translation {\n" + " pool SOME-SNAT-POOL\n" + " type snat\n" + " }\n" + " source-port preserve\n" + " vlans {\n" + " Vlan2222\n" + " }\n" + " service-down-immediate-action none\n" + " service-policy none\n" + " source 0.0.0.0/0\n" + "}\n" + "Trailing garbage text"; 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