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
Processing...

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 = "^(PageTitle = \"([^\"]*)\")(.*)(<title>)([^<]*)(<\\/title>)(.*)(<h1 id=\"page-title\" class=\"font-36\">)([^<]*)(<\\/h1>)(.*)$"; final String string = "<!-- and this include too -->\n" + "Must include all this too\n" + "<%\n" + "PageTitle = \"Member Access\" \n\n" + "MetaDescription = \"There are a number of degree and education paths that can lead an individual to a career in toxicology. This page is designed to provide those considering a career in toxicology with information on the profession, schooling needed, and more. The content of this page was originally developed as a printed publication called Resource Guide to Careers in Toxicology\"\n\n" + "Keywords = \"SOT, Toxicology, Careers, Resource Guide\"\n\n" + "SocialImage = \"http://209.183.221.233/images/sot_logo.png\"\n\n" + "SocialImageDescription = \"SOT logo\"\n\n" + "SocialURL = \"http://209.183.221.233/login.asp\"\n\n\n\n" + "%>\n" + "<!doctype html>\n" + "<html dir=\"ltr\" lang=\"en\">\n" + "<head>\n" + "<meta charset=\"UTF-8\">\n\n" + "<!-- Meta Tags -->\n" + "<meta name=\"description\" content=\"There are a number of degree and education paths that can lead an individual to a career in toxicology. This page is designed to provide those considering a career in toxicology with information on the profession, schooling needed, and more. The content of this page was originally developed as a printed publication called Resource Guide to Careers in Toxicology\">\n" + "<meta name=\"keywords\" content= \"SOT, Toxicology, Careers, Resource Guide\">\n" + "<meta name=\"viewport\" content=\"width=device-width, initial-scale=1.0 shrink-to-fit=no\">\n" + "<meta name=\"author\" content=\"Society of Toxicology\" />\n" + "<meta name =\"robots\" content=\"index\" >\n\n" + "<!-- Twitter and Facebook Social media tags -->\n" + "<meta property=\"fb:app_id\" content=\"309282950004135\" />\n" + "<meta property=\"og:title\" content=\"New Experiences in Toxicology Program\" >\n" + "<meta property=\"og:description\" content=\"There are a number of degree and education paths that can lead an individual to a career in toxicology. This page is designed to provide those considering a career in toxicology with information on the profession, schooling needed, and more. The content of this page was originally developed as a printed publication called Resource Guide to Careers in Toxicology\">\n" + "<meta property=\"og:image\" content=\"http://209.183.221.233/images/sot_logo.png\">\n" + "<meta property=\"og:url\" content=\"http://209.183.221.233/education/st/next.asp\">\n" + "<meta property=\"og:type\" content=\"website\" />\n\n" + "<!-- Non-Essential, But Recommended -->\n" + "<meta property=\"og:site_name\" content=\"Society of Toxicology\">\n" + "<meta name=\"twitter:card\" content=\"summary_large_image\">\n" + "<meta name=\"twitter:image:alt\" content= \"SOT logo\">\n" + "<meta name=\"twitter:creator\" content=\"@SOToxicology\" />\n\n" + "<!-- Non-Essential, But Required for Analytics -->\n" + "<meta name=\"twitter:site\" content=\"@SOToxicology\">\n\n" + "<!-- Follow Facebook's recommendation of a minimum dimension of 1200x630 pixels and an aspect ratio of 1.91:1, but adhere to Twitter's file size requirement of less than 1MB.--> \n\n" + "<!-- Page Title -->\n" + "<title>New Experiences in Toxicology Program</title>\n\n\n" + "<!-- #include virtual=\"/_includes/header_newsite_trt.asp\" --> \n" + " \n" + " \n" + "<div id=\"main\" class=\"main-content\">\n" + " <section class=\"inner-header divider layer-overlay overlay-dark-4\" data-bg-img=\"/images/_interior-banners/About-banner.jpg\" style=\"background-image: url('/images/_interior-banners/About-banner.jpg'); \">\n" + " <div class=\"container pt-30 pb-30\"> \n" + " <!-- Section Content -->\n" + " <div class=\"section-content\">\n" + " <div class=\"row\">\n" + " <div class=\"col-md-6\">\n" + " <h1 id=\"page-title\" class=\"font-36\">New Experiences in Toxicology Program</h1>\n" + " <ol class=\"breadcrumb text-left mt-10 white\">\n" + " <li class=\"active\">New Experiences in Toxicology Program</li>\n" + " </ol>\n" + " </div>\n" + " </div>\n" + " </div>\n" + " </div>\n" + " </section>\n" + "<!-- #include virtual=\"/_includes/social-buttons.asp\" --> \n\n" + "<!-- Indvidual Page Content Below -->\n\n" + "<!-- #include virtual=\"/_global/SOTLogin.asp\" -->\n" + "<!-- Section: Paragraph --->\n" + " <section>\n" + " <div class=\"container \">\n" + " <div class=\"section-content\">\n" + "<CENTER>\n" + " <TABLE width=500>\n" + " <TR> \n" + " <TD height=\"0\" width=\"226\"></TD>\n" + " <TD width=\"108\"></TD>\n" + " </TR>\n" + " <TR>\n" + " <TD height=\"211\" valign=\"top\"> \n" + " <TABLE >\n" + " <TR>\n" + " <TD align=center height=\"185\">\n" + " <noscript>\n" + " Javascript not enabled. <BR>Membership functions are not available.\n" + " </noscript>\n" + " \n" + " <% If Request.Cookies(\"sot-session-id\") <> \"\" Then %>\n" + " <h3>You are now logged in.<br>Please wait for the page to be redirected.</h3>\n" + " <meta http-equiv='refresh' content='1;url=/'>\n" + " <% End If %>\n" + " \n" + " </font></TD>\n" + " </TR>\n" + " </TABLE>\n" + " \n" + " </TD>\n" + " <TD height=\"211\"></TD>\n" + " </TR>\n" + " </TABLE>\n" + "</CENTER>\n\n" + " </div>\n" + " <!-- /columns --> \n" + " \n" + " </div>\n" + " </section>\n" + " <!-- /section Full paragraph ends--> \n" + " \n\n" + "<!-- #include virtual=\"/_includes/footer.asp\" --> "; final String subst = "$1$3$4$2$6$7$8$2$10$11"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE | Pattern.DOTALL); 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