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 = ".*Version (\\S+)"; final String string = "//Version 1.0 Aug 31st 2011 -First Release.\n" + "//Version 1.1 Sep 29th 2011 \n" + "//Bug fixed: When using hovercard in hovercard, the inner hovercard shows up as well when parent hovercard opens.\n" + "//\n" + "//Version 1.2 Sep 30th 2011\n" + "//Enhancement: The hovercard now adjust (either open on left or right) in accordance to the view port.\n" + "//Added options:\n" + "//openOnLeft: force hovercard to open on left. (eg: if the hovered name appear in the end of sentence)\n" + "//\n" + "//Version 2.0 Nov 8th 2011\n" + "//Bug Fixes: zindex issue.\n" + "//Enhancements: Supercool built in social profile cards like Twitter and Facebook!\n" + "//Added options:\n" + "//showTwitterCard: displays a built in twitter card format for a twitter screenname. Maximum 150 twitter lookup per hour.\n" + "//twitterScreenName: twitter screen name for the hovercard. If no username/screenname is provided, hovercard attempts to look up for hovered text.\n" + "//showFacebookCard: displays a built in facebook card format for a facebook username/pages/events etc. Works best with Facebook pages.\n" + "//facebookUserName: facebook username/pages/events/groups for the hovercard. If no username is provided, hovercard attempts to look up for hovered text.\n" + "//\n" + "//Version 2.1 Nov 22nd 2011\n" + "//Enhancement: attribute 'data-hovercard'. You may now use data-hovercard attribute with your label/link etc to set the twitter or facebook usernames.\n" + "//Added options:\n" + "//showCustomCard: You may now add your own custom data source and display the profile data using existing card format.\n" + "//\n" + "//Version 2.2 Dec 9th 2011\n" + "//Bug Fixes: zindex issue with IE7.\n" + "//\n" + "//Version 2.3 Dec 15th 2011\n" + "//Enhancement: The plugin now auto adjust on the edges of visible window/viewport!\n" + "//Added options:\n" + "//openOnTop: Set 'openOnTop' to true if you want the hovercard to always open on left.\n" + "//customCardJSON: Provide a local json data with showCustomCard. Inherits plugin's social card format/styles.\n" + "//delay: Delay the hovercard appearance on hover.\n" + "//\n" + "//Version 2.4 Apr 12th 2012\n" + "//Added options:\n" + "//autoAdjust: The plugin's default functionality to auto adjust to the viewport "; 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