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 = "address\\s*\\d+\\s*range\\s(?<srcIp1>\\S+)\\s*(?<srcIp2>\\S+)"; final String string = "[USG6300E]display current-configuration\n" + "#\n" + "ip service-set TCP-TSGZ type object 514\n" + " service 0 protocol tcp source-port 8801 to 8804 destination-port 0 to 65535\n" + " service 1 protocol tcp source-port 12404 destination-port 0 to 65535\n" + "#\n" + "ip service-set GWDK type object 515\n" + " service 0 protocol tcp source-port 0 to 65535 destination-port 135\n" + " service 1 protocol tcp source-port 0 to 65535 destination-port 137 to 139\n" + " service 2 protocol tcp source-port 0 to 65535 destination-port 445\n" + " service 3 protocol tcp source-port 0 to 65535 destination-port 3389\n" + " service 4 protocol udp source-port 0 to 65535 destination-port 135\n" + " service 5 protocol udp source-port 0 to 65535 destination-port 137 to 139\n" + " service 6 protocol udp source-port 0 to 65535 destination-port 445\n" + " service 7 protocol udp source-port 0 to 65535 destination-port 3389\n" + "#\n" + "ip service-set FXTCP2403 type object 516\n" + " service 0 protocol tcp source-port 0 to 65535 destination-port 2403\n" + "#\n" + "ip service-set FXTCP2404 type object 517\n" + " service 0 protocol tcp source-port 0 to 65535 destination-port 2404\n" + "#\n" + "ip service-set FXTCPTSGZ type object 518\n" + " service 0 protocol tcp source-port 0 to 65535 destination-port 8801 to 8804\n" + " service 1 protocol tcp source-port 0 to 65535 destination-port 12404\n" + "#\n" + "ip service-set TCP5149 type object 519\n" + " service 0 protocol tcp source-port 0 to 65535 destination-port 5149 to 5150\n" + "#\n" + "ip service-set FXTCP5149 type object 520\n" + " service 0 protocol tcp source-port 5149 to 5150 destination-port 0 to 65535\n" + "#\n" + "ip service-set syslo type object 521\n" + " service 0 protocol udp source-port 0 to 65535 destination-port 162\n" + " service 1 protocol udp source-port 0 to 65535 destination-port 514\n" + "#\n" + "ip service-set UDPCJ type object 522\n" + " service 0 protocol udp source-port 0 to 65535 destination-port 161\n" + "#\n" + "ip service-set TCP102 type object 523\n" + " service 0 protocol tcp source-port 0 to 65535 destination-port 102\n" + " service 1 protocol tcp source-port 102 destination-port 0 to 65535\n" + "#\n" + "ip service-set serviceg1 type group 0\n" + " service 0 service-set ntp\n" + "#\n" + "ip service-set serviceg2 type group 1\n" + " service 0 service-set serviceg1\n" + " service 1 service-set FXTCPTSGZ\n" + "#\n\n" + "#\n" + "ip address-set TSGZZhu type object\n" + " address 0 range 10.78.48.112 10.78.48.118\n" + "#\n" + "ip address-set TSGZzi type object\n" + " address 0 10.82.186.11 mask 32\n" + "#\n" + "ip address-set JLzhu type object\n" + " address 0 range 10.78.44.1 10.78.44.15\n" + "#\n" + "ip address-set JLzi type object\n" + " address 0 range 10.82.186.5 10.82.186.6\n" + "#\n" + "ip address-set BXzhu type object\n" + " address 0 range 10.78.48.197 10.78.48.200\n" + "#\n" + "ip address-set BXzi type object\n" + " address 0 range 10.82.186.9 10.82.186.10\n" + "#\n" + "ip address-set DICPzhu type object\n" + " address 0 range 10.78.48.39 10.78.48.40\n" + "#\n" + "ip address-set DICPzi type object\n" + " address 0 10.82.186.4 mask 32\n" + "#\n" + "ip address-set erqu type object\n" + " address 0 10.85.186.0 mask 27\n" + "#\n" + "ip address-set addressg1 type group\n" + " address 0 address-set erqu\n" + "#\n" + "ip address-set addressg2 type group\n" + " address 0 address-set addressg1\n" + " address 1 address-set DICPzi\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