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

Substitution

Processing...

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 = "<span.*>(.*?)<\\/span>"; final String string = "<!--WYSIWYG content - do not remove this comment, and never use this identical text in your topics-->\n" + "<p>-- <span class=\"WYSIWYG_LINK\">Main.SeanOReilly</span> - 2017-08-30</p>\n" + "<h1 class=\"TML\">Technology used</h1>\n" + "<p><span class=\"WYSIWYG_LINK\">[[http://www.oracle.com/technetwork/developer-tools/rest-data-services/overview/index.html][ORDS (Oracle REST data services)]]</span></p>\n" + "<h1 class=\"TML\"></h1>\n" + "<h1 class=\"TML\">REST concepts</h1>\n" + "<table border=\"1\" cellspacing=\"1\" cellpadding=\"0\">\n" + "<tbody>\n" + "<tr>\n" + "<td>GET</td>\n" + "<td class=\"align-left\" style=\"text-align: left\">select</td>\n" + "</tr>\n" + "<tr>\n" + "<td>POST</td>\n" + "<td class=\"align-left\" style=\"text-align: left\">insert</td>\n" + "</tr>\n" + "<tr>\n" + "<td>PUT</td>\n" + "<td class=\"align-left\" style=\"text-align: left\">update</td>\n" + "</tr>\n" + "<tr>\n" + "<td>DELETE</td>\n" + "<td class=\"align-left\" style=\"text-align: left\">delete</td>\n" + "</tr>\n" + "</tbody>\n" + "</table>\n" + "<h1 class=\"TML\"></h1>\n" + "<h1 class=\"TML\">Settings</h1>\n" + "<p><img title=\"ORDS_ords_admin.JPG\" src=\"http://itwiki.core.kmtltd.net.au/pub/Main/SupplyChainIntl/RESTDataAPI/ORDS_ords_admin.JPG\" alt=\"ORDS_ords_admin.JPG\" width=\"356\" height=\"281\" /></p>\n" + "<p><img title=\"ORDS_ords_dev.JPG\" src=\"http://itwiki.core.kmtltd.net.au/pub/Main/SupplyChainIntl/RESTDataAPI/ORDS_ords_dev.JPG\" alt=\"ORDS_ords_dev.JPG\" width=\"356\" height=\"281\" /></p>\n" + "<p><span class=\"WYSIWYG_LINK\">[[http://www.oracle.com/technetwork/developer-tools/rest-data-services/learnmore/index.html]]</span></p>\n" + "<h1 class=\"TML\">Kmart Developer website</h1>\n" + "<p><span class=\"WYSIWYG_LINK\">[[https://developer.core.kmtltd.net.au/]]</span></p>\n" + "<h1 class=\"TML\">Data dictionary</h1>\n" + "<p><span class=\"WYSIWYG_LINK\">ProductNumber</span></p>\n" + "<p><span class=\"WYSIWYG_LINK\">UnitQuantity</span></p>\n" + "<h1 class=\"TML\">Development notes</h1>\n" + "<p>\\\\warthog\\grpdata\\Kmart IT Team\\4. Supply Chain &amp; Finance Delivery\\1. GIF\\1. Apps &amp; Systems\\5. Other\\Tasks\\170823 API</p>\n" + "<h1 class=\"TML\">Examples</h1>\n" + "<h2 class=\"TML\"><span class=\"WYSIWYG_LINK\">AutoREST</span></h2>\n" + "<p><span class=\"WYSIWYG_LINK\">http://kuttsi901:8080/ords/exuts/container/</span></p>\n" + "<h2 class=\"TML\">Configured REST</h2>\n" + "<p><span class=\"WYSIWYG_LINK\">http://kuttsi901:8080/ords/exuts//v1/container/MAEU8378519</span></p>"; final String subst = "\\1"; final Pattern pattern = Pattern.compile(regex); final Matcher matcher = pattern.matcher(string); // The substituted value will be contained in the result variable final String result = matcher.replaceAll(subst); System.out.println("Substitution result: " + result); } }

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