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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

/
/
gm

Test String

Code Generator

Generated Code

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "\\bpayments\\W+(?:\\w+\\W+){1,9}?(?<highlight>\\d{1,3})\\s+?days\\b"; final String string = "Lorem ipsum dolor sit amet, consectetur adipiscing elit. Maecenas at neque eu felis rutrum efficitur. Pellentesque lacinia mauris metus, at dapibus ante varius non. Maecenas non pulvinar velit. Class aptent taciti sociosqu ad litora torquent per conubia nostra, per inceptos himenaeos. Fusce ut risus sollicitudin, interdum dolor condimentum, hendrerit nibh. Donec efficitur sem nisl, ut tristique mauris pulvinar eget. payments must be made within 60 days. Duis eu odio vitae turpis pulvinar placerat vulputate a diam. Maecenas eget risus mauris. Nulla ac convallis erat, a commodo velit. Fusce convallis ultrices neque. Etiam id urna lacus. Mauris fermentum tortor lacus, id congue dui suscipit vitae. Donec mi odio, laoreet a enim et, suscipit varius mauris. Nulla facilisi.--"; 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