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

r"
"
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 = "^((?P<a>[0-9]{1,3})-)?((?P<b>[0-9]{1,3}):)?(?P<cde>(?P<c>[0-9A-F]{1,3}).(?P<d>[0-9A-F]{1,3})(.(?P<e>[0-9A-F]{1,3}))?)([\\*\\&](?P<f>[0-9A-F]{1,3}))?\\((?P<value>[^*^\\)]*)(([\\*])(?P<unit>\\w*))?\\)$"; final String string = "0-1:F.F.0*255(000000000000000)\n" + "0-1:F.F.2*255(000000000111100)\n" + "0-1:0.0.0*255(1ZPA0020280814)\n" + "1-0:C.1.0*255(0020280814)\n" + "1-0:0.0.2*255(4U110017012)\n" + "1-0:0.0.3*255(00000000)\n" + "1-0:0.9.1*255(22:38:32)\n" + "1-0:0.9.2*255(23-12-28)\n" + "1-0:0.2.0*255(05 r01)\n" + "1-0:0.1.2*01(231201000000)\n" + "1-0:0.1.2*02(231101000000)\n" + "1-0:0.1.2*03(231001000000)\n" + "1-0:0.1.2&04(230927075308)\n" + "1-0:1.8.0*255(000003.6382*kWh)\n" + "1-0:1.8.0*254(000003.6382*kWh)\n" + "1-0:1.8.0*01(000003.6382*kWh)\n" + "1-0:1.8.0*02(000003.6382*kWh)\n" + "1-0:1.8.0*03(000003.6382*kWh)\n" + "1-0:1.8.0&04(000000.0000*kWh)\n" + "1-0:1.8.1*255(000003.6382*kWh)\n" + "1-0:1.8.1*254(000003.6382*kWh)\n" + "1-0:1.8.1*01(000003.6382*kWh)\n" + "1-0:1.8.1*02(000003.6382*kWh)\n" + "1-0:1.8.1*03(000003.6382*kWh)\n" + "1-0:1.8.1&04(000000.0000*kWh)\n" + "1-0:1.8.2*255(000000.0000*kWh)\n" + "1-0:1.8.2*254(000000.0000*kWh)\n" + "1-0:1.8.2*01(000000.0000*kWh)\n" + "1-0:1.8.2*02(000000.0000*kWh)\n" + "1-0:1.8.2*03(000000.0000*kWh)\n" + "1-0:1.8.2&04(000000.0000*kWh)\n" + "1-0:2.8.0*255(000000.6248*kWh)\n" + "1-0:2.8.0*254(000000.6248*kWh)\n" + "1-0:2.8.0*01(000000.6248*kWh)\n" + "1-0:2.8.0*02(000000.6248*kWh)\n" + "1-0:2.8.0*03(000000.6248*kWh)\n" + "1-0:2.8.0&04(000000.0000*kWh)\n" + "1-0:2.8.1*255(000000.6248*kWh)\n" + "1-0:2.8.1*254(000000.6248*kWh)\n" + "1-0:2.8.1*01(000000.6248*kWh)\n" + "1-0:2.8.1*02(000000.6248*kWh)\n" + "1-0:2.8.1*03(000000.6248*kWh)\n" + "1-0:2.8.1&04(000000.0000*kWh)\n" + "1-0:2.8.2*255(000000.0000*kWh)\n" + "1-0:2.8.2*254(000000.0000*kWh)\n" + "1-0:2.8.2*01(000000.0000*kWh)\n" + "1-0:2.8.2*02(000000.0000*kWh)\n" + "1-0:2.8.2*03(000000.0000*kWh)\n" + "1-0:2.8.2&04(000000.0000*kWh)\n" + "1-0:0.2.2*255(00750101)\n" + "1-0:C.15.0*255(23-04-07)\n" + "1-0:0.2.6*255(intErn)\n" + "1-0:C.6.0*255(00 00:07:33)\n" + "1-0:C.14.0*255(T2)\n" + "1-0:C.9.0*255(+27.0*C)\n" + "1-0:C.6.3*255(3.66*V)\n" + "1-0:C.1.6*255(98FC51FF)"; 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