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 = "(?smi)^\\|[^\\n]+\\|\\n?\\n"; final String string = "|Runtime version|Shipped with |Internal version|\n" + "|---------------|-----------------------------------|----------------| \n" + "|`1.0` |Business Central April 2018 Release|12.0|\n" + "|`2.0` |Business Central Fall '18 Release |13.0|\n" + "|`3.0` |Business Central Spring '19 Release|14.0|\n" + "|`4.0` |Business Central 2019 release wave 2|15.0|\n" + "|`5.0` |Business Central 2020 release wave 1|16.0|\n" + "|`6.0` |Business Central 2020 release wave 2|17.0|\n" + "|`6.1` |Business Central 2020 release wave 2 update 1|17.1|\n" + "|`6.2` |Business Central 2020 release wave 2 update 2|17.2|\n" + "|`6.3` |Business Central 2020 release wave 2 update 3|17.3|\n" + "|`6.4` |Business Central 2020 release wave 2 update 4|17.4|\n" + "|`7.0` |Business Central 2021 release wave 1|18.0|\n" + "|`7.1` |Business Central 2021 release wave 1 update 1|18.1|\n" + "|`7.2` |Business Central 2021 release wave 1 update 2|18.2|\n" + "|`8.0` |Business Central 2021 release wave 2|19.0|\n" + "|`9.0` |Business Central 2022 release wave 1|20.0|\n" + "|`9.1` |Business Central 2022 release wave 1 update 1|20.1|\n" + "|`9.2` |Business Central 2022 release wave 1 update 2|20.2|\n" + "|`10.0` |Business Central 2022 release wave 2|21.0|\n" + "|`11.0` |Business Central 2023 release wave 1|22.0|\n" + "|`12.0` |Business Central 2023 release wave 2|23.0|\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