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

/
/
xs

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 = " (?si)\n" + " \n" + " ^ \n" + " \n" + " \\s* \n" + " UPDATE \\s+ `mytable` \\s+ \n" + " SET \\s+ `keyname` \\s* = \\s* 'keyvalue'\n\n" + " (?# one or more such key = value )\n" + " (?>\n" + " \\s* , \\s* \n\n" + " (?# field name )\n" + " ` [A-Z_]+ ` \n\n" + " (?# equals )\n" + " \\s* = \\s* \n\n" + " (?# value )\n" + " (?>\n" + " (?# an integer, possibly negative )\n" + " -? [0-9]+ \n" + " | \n" + " (?# or, a string )\n" + " '\n" + " [^'\\\\]* \n" + " (?:\n" + " (?: \\\\ . | '' )\n" + " [^'\\\\]* \n" + " )*\n" + " '\n" + " \n" + " # '\n" + " # (?: [^'\\\\] | '' | \\\\ . )*\n" + " # ' \n" + " \n" + " | \n" + " (?# or, literal NULL )\n" + " NULL \n" + " )\n" + " )+\n" + " \n" + " \\s+ WHERE \\s+ `keyname` \\s* = \\s* 'keyvalue'\n" + " \n" + " $"; final String string = "UPDATE `mytable`\n" + "SET `keyname` = 'keyvalue',\n" + "`Markup` =\n" + "'Lorem ipsum dolor sit amet, consectetur adipiscing elit.\n" + "''Quisque vel mattis odio, quis iaculis sem.''\n" + "Nulla facilisi.\n" + "Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere\n" + "cubilia Curae; Fusce ut dui venenatis, maximus lorem eget, ornare ex.\n" + "Aenean tempus pulvinar est, id fringilla enim sagittis id. Mauris finibus\n" + "cursus commodo.\\r\\n\\r\\n\n" + "Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere\n" + "cubilia Curae; Fusce ut dui venenatis, maximus lorem eget, ornare ex.\n" + "Aenean tempus pulvinar est, id fringilla enim sagittis id. Mauris finibus\n" + "cursus commodo.\\r\\n\\r\\n\\r\\n\n" + "\\'Aenean in augue a est vulputate accumsan.\\'\n" + "Phasellus nulla diam, laoreet a elit non, mattis finibus magna. Phasellus\n" + "faucibus iaculis mi sed pulvinar.\\r\\n\n" + "Aliquam non nisl ultricies, aliquam augue vitae, efficitur sapien.\n" + "Etiam viverra, magna a laoreet sollicitudin, ipsum erat tincidunt sem, nec\n" + "faucibus enim tortor eget massa.Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere\n" + "cubilia Curae; Fusce ut dui venenatis, maximus lorem eget, ornare ex.\n" + "Aenean tempus pulvinar est, id fringilla enim sagittis id. Mauris finibus\n" + "cursus commodo.\\r\\n\\r\\n\n" + "Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere\n" + "cubilia Curae; Fusce ut dui venenatis, maximus lorem eget, ornare ex.\n" + "Aenean tempus pulvinar est, id fringilla enim sagittis id. Mauris finibus\n" + "cursus commodo.\\r\\n\\r\\n\\r\\n\n" + "\\'Aenean in augue a est vulputate accumsan.\\'\n" + "Phasellus nulla diam, laoreet a elit non, mattis finibus magna. Phasellus\n" + "faucibus iaculis mi sed pulvinar.\\r\\n\n" + "Aliquam non nisl ultricies, aliquam augue vitae, efficitur sapien.\n" + "Etiam viverra, magna a laoreet sollicitudin, ipsum erat tincidunt sem, nec\n" + "faucibus enim tortor eget massa.Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere\n" + "cubilia Curae; Fusce ut dui venenatis, maximus lorem eget, ornare ex.\n" + "Aenean tempus pulvinar est, id fringilla enim sagittis id. Mauris finibus\n" + "cursus commodo.\\r\\n\\r\\n\n" + "Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere\n" + "cubilia Curae; Fusce ut dui venenatis, maximus lorem eget, ornare ex.\n" + "Aenean tempus pulvinar est, id fringilla enim sagittis id. Mauris finibus\n" + "cursus commodo.\\r\\n\\r\\n\\r\\n\n" + "\\'Aenean in augue a est vulputate accumsan.\\'\n" + "Phasellus nulla diam, laoreet a elit non, mattis finibus magna. Phasellus\n" + "faucibus iaculis mi sed pulvinar.\\r\\n\n" + "Aliquam non nisl ultricies, aliquam augue vitae, efficitur sapien.\n" + "Etiam viverra, magna a laoreet sollicitudin, ipsum erat tincidunt sem, nec\n" + "faucibus enim tortor eget massa.Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere\n" + "cubilia Curae; Fusce ut dui venenatis, maximus lorem eget, ornare ex.\n" + "Aenean tempus pulvinar est, id fringilla enim sagittis id. Mauris finibus\n" + "cursus commodo.\\r\\n\\r\\n\n" + "Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere\n" + "cubilia Curae; Fusce ut dui venenatis, maximus lorem eget, ornare ex.\n" + "Aenean tempus pulvinar est, id fringilla enim sagittis id. Mauris finibus\n" + "cursus commodo.\\r\\n\\r\\n\\r\\n\n" + "\\'Aenean in augue a est vulputate accumsan.\\'\n" + "Phasellus nulla diam, laoreet a elit non, mattis finibus magna. Phasellus\n" + "faucibus iaculis mi sed pulvinar.\\r\\n\n" + "Aliquam non nisl ultricies, aliquam augue vitae, efficitur sapien.\n" + "Etiam viverra, magna a laoreet sollicitudin, ipsum erat tincidunt sem, nec\n" + "faucibus enim tortor eget massa.Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere\n" + "cubilia Curae; Fusce ut dui venenatis, maximus lorem eget, ornare ex.\n" + "Aenean tempus pulvinar est, id fringilla enim sagittis id. Mauris finibus\n" + "cursus commodo.\\r\\n\\r\\n\n" + "Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere\n" + "cubilia Curae; Fusce ut dui venenatis, maximus lorem eget, ornare ex.\n" + "Aenean tempus pulvinar est, id fringilla enim sagittis id. Mauris finibus\n" + "cursus commodo.\\r\\n\\r\\n\\r\\n\n" + "\\'Aenean in augue a est vulputate accumsan.\\'\n" + "Phasellus nulla diam, laoreet a elit non, mattis finibus magna. Phasellus\n" + "faucibus iaculis mi sed pulvinar.\\r\\n\n" + "Aliquam non nisl ultricies, aliquam augue vitae, efficitur sapien.\n" + "Etiam viverra, magna a laoreet sollicitudin, ipsum erat tincidunt sem, nec\n" + "faucibus enim tortor eget massa.Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere\n" + "cubilia Curae; Fusce ut dui venenatis, maximus lorem eget, ornare ex.\n" + "Aenean tempus pulvinar est, id fringilla enim sagittis id. Mauris finibus\n" + "cursus commodo.\\r\\n\\r\\n\n" + "Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere\n" + "cubilia Curae; Fusce ut dui venenatis, maximus lorem eget, ornare ex.\n" + "Aenean tempus pulvinar est, id fringilla enim sagittis id. Mauris finibus\n" + "cursus commodo.\\r\\n\\r\\n\\r\\n\n" + "\\'Aenean in augue a est vulputate accumsan.\\'\n" + "Phasellus nulla diam, laoreet a elit non, mattis finibus magna. Phasellus\n" + "faucibus iaculis mi sed pulvinar.\\r\\n\n" + "Aliquam non nisl ultricies, aliquam augue vitae, efficitur sapien.\n" + "Etiam viverra, magna a laoreet sollicitudin, ipsum erat tincidunt sem, nec\n" + "faucibus enim tortor eget massa.\n" + "Nunc nisi orci, lacinia vitae dictum et, vestibulum sed metus. ',\n" + "`From_Date` = NULL,\n" + "`To_Date` = NULL,\n" + "`Foo` = '',\n" + "`Box_Colour` = NULL,\n" + "`Modification_Date` = '2016-09-08 12:30:47',\n" + "`Modified_User` = 1,\n" + "`Modified_IP` = '192.168.1.1'\n" + "WHERE `keyname` = 'keyvalue'"; final Pattern pattern = Pattern.compile(regex, Pattern.COMMENTS | Pattern.DOTALL); final Matcher matcher = pattern.matcher(string); if (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