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

/
/
g

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 = "(2014[0-5]{2}|20[0-3]{2}[0-9]{2})"; final String string = "/var/www/u4534146/data/www/nordfarm89.ru/administrator/components/com_akeeba/backup/site-nordfarm89.ru-20130717-053058.jpa\n" + "/var/www/u4534146/data/www/nordfarm89.ru/administrator/components/com_akeeba/backup/site-nordfarm89.ru-20140707-145230.jpa\n" + "/var/www/u4534146/data/www/xn--80adpfjfv6e5c.xn--p1ai/administrator/components/com_akeeba/backup/site-www.xn--80adpfjfv6e5c.xn--p1ai-20140707-141309.jpa\n" + "/var/www/u4551186/data/www/lovozero.net/administrator/components/com_akeeba/backup/site-lovozero.net-20140506-182906.jpa\n" + "/var/www/u4551186/data/www/lovozero.net/administrator/components/com_akeeba/backup/site-lovozero.net-20140721-091725.jpa\n" + "/var/www/u4551186/data/www/ruslapland.com/administrator/components/com_akeeba/backup/site-ruslapland.com-20140505-055235.jpa\n" + "/var/www/u4656806/data/www/flowerskhv.ru/administrator/components/com_akeeba/backup/site-flowerskhv.ru-20130801-083230.zip\n" + "/var/www/u4656806/data/www/flowerskhv.ru/administrator/components/com_akeeba/backup/site-flowerskhv.ru-20130801-080342.jpa\n" + "/var/www/u4763625/data/www/spbkk.org/administrator/components/com_akeeba/backup/site-www.spbkk.org-20131202-081827.z01\n" + "/var/www/u6412275/data/www/keramicheskaya-cherepitsa.ru/administrator/components/com_akeeba/backup/site-koramic7.ru-20140615-113953.zip\n" + "/var/www/u6412275/data/www/keramicheskaya-cherepitsa.ru/administrator/components/com_akeeba/backup/site-koramic7.ru-20140615-115049.zip\n" + "/var/www/u6559515/data/www/division.nnov.ru/administrator/components/com_akeeba/backup/site-division.nnov.ru-20130814-124501.jpa\n" + "/var/www/u7357881/data/www/na-odo.ru/administrator/components/com_akeeba/backup/site-na-odo.ru-20131004-051700.jpa\n" + "/var/www/u7357881/data/www/na-odo.ru/administrator/components/com_akeeba/backup/site-na-odo.ru-20131001-103321.jpa\n" + "/var/www/u7357881/data/www/na-odo.ru/administrator/components/com_akeeba/backup/site-na-odo.ru-20130918-132300.jpa\n" + "/var/www/u7357881/data/www/www.na-odo.ru/administrator/components/com_akeeba/backup/site-na-odo.ru-20131004-051700.jpa\n" + "/var/www/u7357881/data/www/www.na-odo.ru/administrator/components/com_akeeba/backup/site-na-odo.ru-20131001-103321.jpa\n" + "/var/www/u7357881/data/www/www.na-odo.ru/administrator/components/com_akeeba/backup/site-na-odo.ru-20130918-132300.jpa\n" + "/var/www/u7726504/data/www/injinterior.com/administrator/components/com_akeeba/backup/site-injinterior.com-20131002-163453.zip\n" + "[root@server41 ~]# find /var/www/*/data/www/*/administrator/components/com_akeeba/backup/ -size +50M -type f -regextype posix-extended -regex '.+20[0-9].+'\n" + "/var/www/u0017144/data/www/camper.diamonds/administrator/components/com_akeeba/backup/site-camper.diamonds-20140702-232727.jpa\n" + "/var/www/u0017144/data/www/camper.diamonds/administrator/components/com_akeeba/backup/site-camper.diamonds-20140703-115210.jpa\n" + "/var/www/u0017144/data/www/camper.diamonds/administrator/components/com_akeeba/backup/site-camper.diamonds-20140703-095129.jpa\n" + "/var/www/u3669070/data/www/empyrio.com/administrator/components/com_akeeba/backup/site-empyrio.com-20130531-180641.zip\n" + "/var/www/u3669070/data/www/empyrio.com/administrator/components/com_akeeba/backup/site-empyrio.com-20130706-065422.zip\n" + "/var/www/u3669070/data/www/empyrio.com/administrator/components/com_akeeba/backup/site-empyrio.com-20130511-104029.zip\n" + "/var/www/u3671785/data/www/coffeetehnika.ru/administrator/components/com_akeeba/backup/site-coffeetehnika.ru-20140701-134919.jpa\n" + "/var/www/u3671785/data/www/www.coffeetehnika.ru/administrator/components/com_akeeba/backup/site-coffeetehnika.ru-20140701-134919.jpa\n" + "/var/www/u3677644/data/www/lea/administrator/components/com_akeeba/backup/site-www.luxury-escort-agency.ru-20130524-133127.jpa\n" + "/var/www/u3704435/data/www/spacegiraffe.ru/administrator/components/com_akeeba/backup/site-spacegiraffe.ru-20120321-150956.jpa\n" + "/var/www/u3708456/data/www/astron-fit.ru/administrator/components/com_akeeba/backup/site-astron-fit.ru-20121015-123938.jpa\n" + "/var/www/u3708456/data/www/astron-fit.ru/administrator/components/com_akeeba/backup/site-astron-fit.ru-20130225-140418.jpa\n" + "/var/www/u4409328/data/www/logitechstore.ru/administrator/components/com_akeeba/backup/site-logitechstore.ru-20140720-145007.zip\n" + "/var/www/u4534146/data/www/100-89.ru/administrator/components/com_akeeba/backup/site-100-89.ru-20140611-205311.jpa\n" + "/var/www/u4534146/data/www/100-89.ru/administrator/components/com_akeeba/backup/site-100-89.ru-20140611-211200.jpa\n" + "/var/www/u4534146/data/www/nordfarm89.ru/administrator/components/com_akeeba/backup/site-nordfarm89.ru-20130717-054930.jpa\n" + "/var/www/u4534146/data/www/nordfarm89.ru/administrator/components/com_akeeba/backup/site-nordfarm89.ru-20140218-061451.jpa\n" + "/var/www/u4534146/data/www/nordfarm89.ru/administrator/components/com_akeeba/backup/site-nordfarm89.ru-20130717-053058.jpa\n" + "/var/www/u4534146/data/www/nordfarm89.ru/administrator/components/com_akeeba/backup/site-nordfarm89.ru-20140707-145230.jpa\n" + "/var/www/u4534146/data/www/xn--80adpfjfv6e5c.xn--p1ai/administrator/components/com_akeeba/backup/site-www.xn--80adpfjfv6e5c.xn--p1ai-20140707-141309.jpa\n" + "/var/www/u4551186/data/www/lovozero.net/administrator/components/com_akeeba/backup/site-lovozero.net-20140506-182906.jpa\n" + "/var/www/u4551186/data/www/lovozero.net/administrator/components/com_akeeba/backup/site-lovozero.net-20140721-091725.jpa\n" + "/var/www/u4551186/data/www/ruslapland.com/administrator/components/com_akeeba/backup/site-ruslapland.com-20140505-055235.jpa\n" + "/var/www/u4656806/data/www/flowerskhv.ru/administrator/components/com_akeeba/backup/site-flowerskhv.ru-20130801-083230.zip\n" + "/var/www/u4656806/data/www/flowerskhv.ru/administrator/components/com_akeeba/backup/site-flowerskhv.ru-20130801-080342.jpa\n" + "/var/www/u4763625/data/www/spbkk.org/administrator/components/com_akeeba/backup/site-www.spbkk.org-20131202-081827.z01\n" + "/var/www/u6412275/data/www/keramicheskaya-cherepitsa.ru/administrator/components/com_akeeba/backup/site-koramic7.ru-20140615-113953.zip\n" + "/var/www/u6412275/data/www/keramicheskaya-cherepitsa.ru/administrator/components/com_akeeba/backup/site-koramic7.ru-20140615-115049.zip\n" + "/var/www/u6559515/data/www/division.nnov.ru/administrator/components/com_akeeba/backup/site-division.nnov.ru-20130814-124501.jpa\n" + "/var/www/u7357881/data/www/na-odo.ru/administrator/components/com_akeeba/backup/site-na-odo.ru-20131004-051700.jpa\n" + "/var/www/u7357881/data/www/na-odo.ru/administrator/components/com_akeeba/backup/site-na-odo.ru-20131001-103321.jpa\n" + "/var/www/u7357881/data/www/na-odo.ru/administrator/components/com_akeeba/backup/site-na-odo.ru-20130918-132300.jpa"; final Pattern pattern = Pattern.compile(regex); 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