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
Processing...

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 = "(?m)^\\#[^\\S\\r\\n]*(\\S+).*\\s+^(?!\\#)[^\\S\\r\\n]*(\\S+)"; final String string = "# Arista \n" + "# aristaBgp4V2EstablishedNotification aristaBgp4V2PeerState\n" + "1.3.6.1.4.1.30065.4.1.0.1 0x06710000 1.3.6.1.4.1.30065.4.1.1.2.1.13(1,2)\\\n" + " # aristaBgp4V2PeerLocalPort\n" + " 1.3.6.1.4.1.30065.4.1.1.2.1.6(3,0)\\\n" + " # aristaBgp4V2PeerRemotePort\n" + " 1.3.6.1.4.1.30065.4.1.1.2.1.9(4,0)\n" + "# aristaBgp4V2BackwardTransitionNotificationaristaBgp4V2PeerState\n\n\n" + "1.3.6.1.4.1.30065.4.1.0.2 0x06710001 1.3.6.1.4.1.30065.4.1.1.2.1.13(1,2)\\\n" + " # aristaBgp4V2PeerLocalPort\n" + " 1.3.6.1.4.1.30065.4.1.1.2.1.6(3,0)\\\n" + " # aristaBgp4V2PeerRemotePort\n" + " 1.3.6.1.4.1.30065.4.1.1.2.1.9(4,0)\\\n" + " # aristaBgp4V2PeerLastErrorCodeReceived\n" + " 1.3.6.1.4.1.30065.4.1.1.3.1.1(5,0)\\\n" + " # aristaBgp4V2PeerLastErrorSubCodeReceived\n" + " 1.3.6.1.4.1.30065.4.1.1.3.1.2(6,0)\\\n" + " # aristaBgp4V2PeerLastErrorReceivedText\n" + " 1.3.6.1.4.1.30065.4.1.1.3.1.4(7,0)\n" + "#portTestResultNotification\n\n" + "1.3.6.1.4.1.4998.1.1.10.1.0.14 0x048a000d 1.3.6.1.4.1.4998.1.1.10.1.1.2(1,0)\\\n" + " 1.3.6.1.4.1.4998.1.1.10.1.1.3(2,0)\\\n" + " 1.3.6.1.4.1.4998.1.1.10.1.2.1(3,0)\\\n" + " 1.3.6.1.4.1.4998.1.1.10.1.1.98(4,0)\\\n" + " 1.3.6.1.4.1.4998.1.1.10.1.1.99(5,0)\\\n" + " 1.3.6.1.4.1.4998.1.1.10.1.5.4.1.5(6,7)\\\n" + " 1.3.6.1.4.1.4998.1.1.10.1.5.4.1.12(8,0)\\\n" + " 1.3.6.1.4.1.4998.1.1.10.1.5.4.1.13(9,0)\\\n" + " 1.3.6.1.4.1.4998.1.1.10.1.5.4.1.14(10,0)\n\n" + "# BigIp \n" + "#diskVolumeUsageNotification\n\n" + "1.3.6.1.4.1.4998.1.1.10.1.0.17 0x048a000e 1.3.6.1.4.1.4998.1.1.10.1.1.2(1,0)\\\n" + " 1.3.6.1.4.1.4998.1.1.10.1.1.3(2,0)\\\n" + " 1.3.6.1.4.1.4998.1.1.10.1.2.1(3,0)\\\n" + " 1.3.6.1.4.1.4998.1.1.10.1.1.98(4,0)\\\n" + " 1.3.6.1.4.1.4998.1.1.10.1.1.100(5,0)\\\n" + " 1.3.6.1.4.1.4998.1.1.10.1.1.101(6,0)\\\n" + " 1.3.6.1.4.1.4998.1.1.10.1.4.4.1.7(7,8)\\\n" + " 1.3.6.1.4.1.4998.1.1.10.1.4.4.1.5(9,0)\n\n" + "1.3.6.1.4.1.30065.3.8.1.0.1 0x06710004 1.3.6.1.4.1.30065.3.8.0.0.3.1.3(1,2)\\\n" + " # aristaRedundancyLastSwOverReason\n" + " 1.3.6.1.4.1.30065.3.8.0.0.4(3,0)\n\n" + "# wlsrStaImpersonation wlsrNodeMac\n" + "1.3.6.1.4.1.14823.2.3.1.1.100.6.1002 0x05f7000f 1.3.6.1.4.1.14823.2.3.1.1.100.100.5(1,0)\\\n" + " # wlsrLocation\n" + " 1.3.6.1.4.1.14823.2.3.1.1.1.1.1.20(2,3)\n\n\n"; final Pattern pattern = Pattern.compile(regex); 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