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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

r"
"
gm

Test String

Code Generator

Generated Code

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "(?:(?:^edit\\ \\\"(.+)\\\"$\\n)(?:^set\\ uuid\\ ([a-f0-9]{8}\\-(?:[a-f0-9]{4}\\-){3}[a-f0-9]{12})$\\n)(?:(?:^set\\ comment\\ )((?:(?!^set\\ )(?:.*$\\n))+)(?=^set\\ ))?(?:^set\\ service\\ (\\\".+\\\")$\\n)?(?:^set\\ extip\\ ((?:(?:\\d{1,3}\\.){3}(?:\\d{1,3}))(?:\\-(?:\\d{1,3}\\.){3}(?:\\d{1,3}))?)$\\n)(?:^set\\ extintf\\ \\\"(.+)\\\"$\\n)(?:^(set\\ portforward)\\ (enable)$\\n)?(?:^(set\\ color)\\ (\\d{1,2})$\\n)?(?:^set\\ mappedip\\ \\\"((?:(?:\\d{1,3}\\.){3}(?:\\d{1,3}))(?:\\-(?:\\d{1,3}\\.){3}(?:\\d{1,3}))?)\\\"$\\n)(?:^(set\\ protocol)\\ (.+)$\\n)?(?:^(set\\ extport)\\ (\\d{1,5}(?:\\-\\d{1,5})?)$\\n)?(?:^(set\\ mappedport)\\ (\\d{1,5}(?:\\-\\d{1,5})?)$\\n)?(?:^next$\\n(?:^$\\n)?))"; final String string = "edit \"VIP [DNS сервер site.com]\"\n" + "set uuid abcdef01-2345-6789-abcd-ef0123456789\n" + "set comment \"Публикация IP-адреса для проекта \n" + "\\\"TEST\\\" в ДЦ \\\"Облако\\\"\"\n" + "set service \"HTTP Webserver\"\n" + "set extip 100.200.254.20\n" + "set extintf \"DMZ [VLAN 100]\"\n" + "set portforward enable\n" + "set color 3\n" + "set mappedip \"10.100.200.5\"\n" + "set protocol udp\n" + "set extport 53\n" + "set mappedport 2000-65535\n" + "next\n\n" + "edit \"VIP [NTP сервер site.com]\"\n" + "set uuid abcdef01-2345-6789-abcd-ef0123456789\n" + "set comment \"Публикация IP-адреса для проекта \n" + "\\\"TEST\\\" в ДЦ \\\"Облако\\\"\"\n" + "set service \"NTP TCP Server\" \"NTP UDP Server\"\n" + "set extip 100.200.254.20-100.200.254.21\n" + "set extintf \"DMZ [VLAN 100]\"\n" + "set portforward enable\n" + "set color 3\n" + "set mappedip \"10.100.200.5-10.100.200.6\"\n" + "set protocol udp\n" + "set extport 123\n" + "set mappedport 1000-1999\n" + "next\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