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

/
/
g

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 = "(NAME)((\\s)?:(\\s)?)([ |,| (|)|\\\\|\\.|\\\"|\\w|\\-|\\+]*)((\\s)*?,(\\s)*?)(DESCR)((\\s)?:(\\s)?)([ |,| (|)|\\\\|\\.|\\\"|\\w|\\-|\\+]*)(\\s)(PID)((\\s)?:(\\s)?)([\\w|\\-|\\+|=]+)((\\s)+,(\\s)+)(VID)((\\s)?:(\\s)?)([\\w| ]*)((\\s)+,(\\s)+)(SN)((\\s)?:(\\s)?)([\\w| ]*)"; final String string = "WDL3-4N-C4510-1A#show inventory\n" + "NAME: \"Switch System\", DESCR: \"Cisco Systems, Inc. WS-C4510R+E 10 slot switch \"\n" + "PID: WS-C4510R+E , VID: V03 , SN: FOX1616GNS8\n\n" + "NAME: \"Clock Module\", DESCR: \"Clock Module\"\n" + "PID: WS-X4K-CLOCK-E , VID: V01 , SN: NWG161794PT\n\n" + "NAME: \"Mux Buffer 1 \", DESCR: \"Mux Buffers for Redundancy Logic\"\n" + "PID: WS-X4590-EX= , VID: , SN: NWG16179CP9\n\n" + "NAME: \"Mux Buffer 2 \", DESCR: \"Mux Buffers for Redundancy Logic\"\n" + "PID: WS-X4590-EX= , VID: , SN: NWG16179C3T\n\n" + "NAME: \"Mux Buffer 3 \", DESCR: \"Mux Buffers for Redundancy Logic\"\n" + "PID: WS-X4590-EX= , VID: , SN: NWG16179CUN\n\n" + "NAME: \"Mux Buffer 4 \", DESCR: \"Mux Buffers for Redundancy Logic\"\n" + "PID: WS-X4590-EX= , VID: , SN: NWG16179AXZ\n\n" + "NAME: \"Mux Buffer 7 \", DESCR: \"Mux Buffers for Redundancy Logic\"\n" + "PID: WS-X4590-EX= , VID: , SN: NWG16179CTE\n\n" + "NAME: \"Mux Buffer 8 \", DESCR: \"Mux Buffers for Redundancy Logic\"\n" + "PID: WS-X4590-EX= , VID: , SN: NWG16179C3V\n\n" + "NAME: \"Mux Buffer 9 \", DESCR: \"Mux Buffers for Redundancy Logic\"\n" + "PID: WS-X4590-EX= , VID: , SN: NWG16179CLW\n\n" + "NAME: \"Mux Buffer 10 \", DESCR: \"Mux Buffers for Redundancy Logic\"\n" + "PID: WS-X4590-EX= , VID: , SN: NWG16179CVU\n\n" + "NAME: \"Linecard(slot 1)\", DESCR: \"10/100/1000BaseT (RJ45)+V E Series with 48 10/100/1000 baseT Premium PoE ports (Cisco/IEEE)\"\n" + "PID: WS-X4748-RJ45V+E , VID: V03 , SN: CAT1624L2J7\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