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 = "(?:(?<!\\d|\\-|\\+|\\.)(?P<ch_a>[\\u4e00-\\u9fff]{2})?(?P<Hours>[0-2]?\\d)(?:[:\\.时時]| ?h ?)(?P<Minutes>[0-5]\\d(?!\\d))\\:?(?:(?:[:\\.分]| ?m ?)(?P<Seconds>[0-5]\\d(?!\\d)))?秒?(?:[,\\.](?P<SecodsFraction>\\d{9}|\\d{6}|\\d{3}(?!\\d)))?(?:\\ \\w\\W)?(?:[\\.\\s]?(?:(?P<Z>(?:[a-zA-Z]{3,5}|Z|\\[\\w+\\/\\w+\\])|(?:[+-]\\d\\d?\\:?[0,3,4]?[0,5]?))|(?P<a>[dapmDAPM]{2})))*(?!\\S))"; final String string = "19990322+0100\n" + "19990322\n" + "1999-03-22 AD\n" + "1999-03-22+01:00\n" + "1999-03-22T05:06:07.000[Europe/Paris]\n" + "1999-03-22T05:06:07.000\n" + "1999-03-22T05:06:07\n" + "1999-03-22T05:06:07.000Z\n" + "1999-03-22T05:06:07.000+01:00\n" + "1999-03-22T05:06:07+01:00\n" + "1999-081+01:00\n" + "1999W132\n" + "1999-W13-2\n" + "1999-03-22T05:06:07.000+01:00[Europe/Paris]\n" + "1999-03-22T05:06:07+01:00[Europe/Paris]\n" + "22.3.99\n" + "22.3.99 5.06\n" + "22.3.1999 5.06.07\n" + "22.3.1999 5:06:07\n" + "22-03-99\n" + "22-03-99 05:06\n" + "22-03-1999 05:06:07\n" + "22.03.99\n" + "22. März 1999\n" + "Montag, 22. März 1999\n" + "22.03.1999\n" + "22.03.99 05:06\n" + "22. März 1999 05:06:07 MEZ\n" + "22.03.1999 05:06:07\n" + "22.03.99 05:06:07\n" + "22.03.1999 05:06\n" + "Montag, 22. März 1999 05:06 Uhr MEZ\n" + "22-Mar-1999\n" + "22/03/99 5:06 AM\n" + "Monday, March 22, 1999 5:06:07 o'clock AM CET\n" + "22-Mar-1999 5:06:07 AM\n" + "22 March 1999\n" + "Monday, 22 March 1999\n" + "22-Mar-1999\n" + "22 March 1999 05:06:07 CET\n" + "Monday, 22 March 1999 05:06:07 o'clock CET\n" + "22-Mar-1999 05:06:07\n" + "22-Mar-99 05.06.07.000000888 AM\n" + "3/22/99\n" + "03/11/22\n" + "03-22-99\n" + "3-22-99\n" + "Mar 22, 1999\n" + "March 22, 1999\n" + "Monday, March 22, 1999\n" + "Mar 22 1999\n" + "March 22 1999\n" + "03-22-1999\n" + "3-22-1999\n" + "1999-03-22+01:00\n" + "22/03/1999\n" + "22/3/1999\n" + "03/22/1999\n" + "3/22/1999\n" + "1999/3/22\n" + "3/22/99 5:06 AM\n" + "03/22/99 5:06 AM\n" + "03-22-99 5:06 AM\n" + "3-22-99 5:06 AM\n" + "Mar 22, 1999 5:06:07 AM\n" + "Monday, March 22, 1999 5:06:07 AM CET\n" + "Mon Mar 22 05:06:07 CET 1999\n" + "Mon, 22 Mar 1999 05:06:07 +0100\n" + "22 Mar 1999 05:06:07 +0100\n" + "03-22-1999 5:06:07 AM\n" + "3-22-1999 5:06:07 AM\n" + "1999-03-22 5:06:07 AM\n" + "1999-3-22 5:06:07 AM\n" + "1999-03-22 05:06:07.0\n" + "22/03/1999 5:06:07 AM\n" + "22/3/1999 5:06:07 AM\n" + "03/22/1999 5:06:07 AM\n" + "3/22/1999 5:06:07 AM\n" + "03/22/99 5:06:07 AM\n" + "03/22/99 5:06:07\n" + "3/22/99 5:06:07\n" + "22/03/1999 5:06 AM\n" + "22/3/1999 5:06 AM\n" + "03/22/1999 5:06 AM\n" + "3/22/1999 5:06 AM\n" + "03-22-99 5:06:07 AM\n" + "3-22-99 5:06:07 AM\n" + "03-22-1999 5:06 AM\n" + "3-22-1999 5:06 AM\n" + "1999-03-22 5:06 AM\n" + "1999-3-22 5:06 AM\n" + "Mar.22.1999\n" + "22/Mar/1999 5:06:07 +0100\n" + "22/Mar/99 5:06 AM\n" + "22/03/99\n" + "22/03/99 5:06\n" + "22.3.99 5:06\n" + "22.03.99\n" + "22.03.1999\n" + "22.03.99 5:06\n" + "22.03.1999 5:06:07\n" + "22.3.1999\n" + "22.3.1999 5:06\n" + "99-03-22\n" + "1999-03-22\n" + "22 mars 1999 05:06:07 CET\n" + "March 22, 1999 5:06:07 CET AM\n" + "1999-03-22 05:06:07\n" + "lundi 22 mars 1999 5 h 06 CET\n" + "22/03/99\n" + "22 mars 1999\n" + "22 mars 1999\n" + "lundi 22 mars 1999\n" + "22/03/99 05:06\n" + "03/22/99 05:06\n" + "3/22/99 05:06\n" + "03-22-99 05:06\n" + "3-22-99 05:06\n" + "22 mars 1999 05:06:07\n" + "22 mars 1999 05:06:07 CET\n" + "03-22-1999 05:06:07\n" + "3-22-1999 05:06:07\n" + "1999-3-22 05:06:07\n" + "22/03/1999 05:06:07\n" + "22/3/1999 05:06:07\n" + "03/22/1999 05:06:07\n" + "3/22/1999 05:06:07\n" + "lundi 22 mars 1999 05 h 06 CET\n" + "22/03/99 05:06:07\n" + "03/22/99 05:06:07\n" + "3/22/99 05:06:07\n" + "22/03/1999 05:06\n" + "22/3/1999 05:06\n" + "03/22/1999 05:06\n" + "3/22/1999 05:06\n" + "03-22-99 05:06:07\n" + "3-22-99 05:06:07\n" + "03-22-1999 05:06\n" + "3-22-1999 05:06\n" + "1999-3-22 05:06\n" + "99/03/22 05:06\n" + "1999.03.22\n" + "1999.03.22 05:06:07\n" + "1999.03.22 05:06\n" + "1999.03.22.\n" + "1999.03.22. 5:06:07\n" + "1999.03.22. 5:06\n" + "22.3.1999 05:06:07\n" + "22.3.1999 05:06\n" + "22-mar-1999\n" + "22/03/99 5.06\n" + "99-03-22 05:06\n" + "22-mar-1999 5.06.07\n" + "22 marzo 1999 5.06.07 CET\n" + "lunedì 22 marzo 1999 5.06.07 CET\n" + "05:06 22/03/99\n" + "05:06:07 22/03/1999\n" + "99/03/22\n" + "1999/03/22\n" + "99/03/22 5:06\n" + "03/22/99 5:06\n" + "3/22/99 5:06\n" + "03-22-99 5:06\n" + "3-22-99 5:06 AM\n" + "03-22-1999 5:06:07\n" + "3-22-1999 5:06:07\n" + "1999-03-22 5:06:07\n" + "99/03/22 5:06:07\n" + "3/22/99 5:06:07 AM\n" + "1999/03/22 5:06\n" + "22/03/1999 5:06\n" + "22/3/1999 5:06\n" + "03/22/1999 5:06\n" + "3/22/1999 5:06\n" + "03-22-99 5:06:07\n" + "3-22-99 5:06:07\n" + "03-22-1999 5:06\n" + "3-22-1999 5:06\n" + "1999-03-22 5:06\n" + "1999-3-22 5:06\n" + "99. 3. 22\n" + "1999. 3. 22\n" + "99.3.22\n" + "99.3.22 05.06\n" + "1999-03-22 05.06.07\n" + "99.22.3\n" + "1999.22.3\n" + "99.22.3 05:06\n" + "1999.22.3 05:06:07\n" + "22.3.99 05:06\n" + "22.3.1999 05:06:\n" + "22-3-99\n" + "22-3-99 5:06\n" + "22-03-1999\n" + "22-03-1999 5:06\n" + "22.03.99 5:06\n" + "22.03.1999 5:06:07\n" + "1999-03-22 5:06:07.PD\n" + "99-03-22 5.06.PD\n" + "1999-03-22 5.06.07.PD CET\n" + "22.3.99.\n" + "22.03.1999.\n" + "22.3.99. 05.06\n" + "22.03.1999. 05.06.07\n" + "22.03.1999. 05.06.07 CET\n" + "05:06:07 22-03-1999\n" + "05:06 22/03/1999\n" + "99-3-22\n" + "1999-3-22\n" + "1999年3月22日\n" + "1999年3月22日 星期一\n" + "99-3-22 上午5:06\n" + "1999-3-22 5:06:07\n" + "1999年3月22日 上午05时06分07秒\n" + "1999年3月22日 5時06分07秒 CET\n" + "1999年3月22日 星期一 上午05时06分07秒 CET\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