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

/
/
mig

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 = "^rate\\((?:1\\s(?:hour|minute|day)|(?:[2-9]|[1-9][0-9]+)\\s(?:hours|minutes|days))\\)|cron\\(\\s*(?:\\*|(?<minutes>0|[1-5]{0,1}[0-9]?)(?:(?:,(?P>minutes))*|(?:-(?P>minutes)){0,1}(?:\\/[[:digit:]]){0,1}))\\s\\s*(?:\\*|(?<hours>0|[1]{0,1}[0-9]?|2[0-3])(?:(?:,(?P>hours))*|(?:-(?P>hours)){0,1}(?:\\/[[:digit:]]){0,1}))\\s\\s*(?:(?<qDays>\\?)|\\*(?<days>[1-2]{0,1}[1-9]?|31|10|20|30)(?:(?:,(?P>days))*|(?:-(?P>days)){0,1}(?:\\/[[:digit:]]){0,1}|L|W))\\s\\s*(?:\\*|(?<month>[1-9]|1[0-2])(?:(?:,(?P>month))*|(?:-(?P>month)){0,1}(?:\\/[[:digit:]]){0,1})|(?<alphamonth>JAN|FEB|MAR|APR|MAY|JUN|JUL|AUG|SEP|OCT|NOV|DEC)(?:(?:,(?P>alphamonth))*|(?:-(?P>alphamonth)){0,1}(?:\\/[[:digit:]]){0,1}))\\s\\s*(?(<qDays>)(?:\\*|(?<week>[1-7])(?:(?:,(?P>week))*|(?:-(?P>week)){0,1}(?:\\/[[:digit:]]){0,1}|L|#[1-5])|(?<alphaweek>MON|TUE|WED|THU|FRI|SAT|SUN)(?:(?:,(?P>alphaweek))*|(?:-(?P>alphaweek)){0,1}(?:\\/[[:digit:]]){0,1}))|\\?)\\s\\s*(?:\\*|(?<year>19[7-9][0-9]|2[0-1][0-9][0-9])(?:(?:,(?P>year))*|(?:-(?P>year)){0,1}(?:\\/[[:digit:]]){0,1}))\\s*\\)$"; final String string = "cron(0 10 * * ? *)\n" + "cron(* * * * ? *)\n" + "cron(0 18 ? * MON-FRI *)\n" + "cron(15 10 ? * 6L 2002-2005)\n" + "cron(5,35 14 * * ? *)\n" + "cron(0 8 ? * 1#4 *)\n" + "cron(0 10 * * ? *)\n" + "rate(1 minute)\n" + "rate(5 minutes)\n" + "rate(298 minutes)\n" + "rate(2 minute)\n" + "cron(0 10 * * * *)"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE | Pattern.CASE_INSENSITIVE); 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