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

/
/
gi

Test String

Code Generator

Generated Code

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "(href|src|source|retinaSource|data)=([\"|'][^\"']*assets[^\"']*\\.\\w{1,5})(\\?[^\"']*)?[\"|']"; final String string = "<a href=\"javascript://\" class=\"btn btn-continue-operation disabled\">\n" + " <span>Continuar</span>\n" + " </a>\n\n" + "<a href='javascript://\" class=\"btn btn-continue-operation disabled'>\n" + " <span>Continuar</span>\n" + " </a>\n\n\n" + "<ul class=\"footer-legal l-adjacent-list\">\n" + " <li><a href=\"#external-content//genoma_transactional/cms_files/corporativo/seguridad-internet/index_transaccional.html\" class=\"footer-legal-element clr-gray.html\">{security}</a></li>\n" + " <li><a href='#external-content//genoma_transactional/cms_files/corporativo/sobre-ing/condiciones-servicio-tarifa_transaccional.html' class=\"footer-legal-element clr-gray\">{link-legal-info-footer}</a></li>\n" + "</ul>\n\n" + " <link type=\"text/css\" href=\" assets/custom-css /infobolsa \n\n\n" + ".css\" rel=\"stylesheet\" media=\"all\" charset=\"utf-8\">\n\n" + " <div class=\"fingerprint-views-storage-content-img txt-c\">\n" + " {>pp-image imageId=\"fingerprint-activation\" altText=\"fingerprint-activation\"\n" + " source=\"assets/images/fingerprint-activation.png\"\n" + " retinaSource=\"assets/images/retina/fingerprint-activation@2x.png\"/}\n" + " </div>\n\n" + "<img src=\"modules/cc-menu/assets/images/logo_cc.svg\" alt=\"Components catalog\">\n\n" + "<img src=\"assets/images/twyp_cash_circle.svg?query=34\"> <img src=\"assets/ircle.svg?hgt=76\">\n\n" + "{>pp-image imageId=\"budgets-tutorial-client-step3\" altText=\"budget-tutorial-step3\"\n" + " source=\"components/budgets-tutorial/ASSETS/images/budgets-tutorial-client-step3.png\" {>pp-image imageId=\"budgets-tutorial-client-step3\" altText=\"budget-tutorial-step3\"\n" + " source=\"components/budgets-tutorial/ASSETS/images/budgets-tutorial-client-step3.png\"\n\n" + "{>pp-image source=\"assets/images/svg/logoING.svg\"/}\n\n" + " <div data-selector=\"logo-ing\" class=\"padding-top-sm padding-left-sm pull-left\">\n" + " <img id=\"logo\" src=\"assets/images/svg/logoING.svg\" class=\"img-svg svg-header-logo login-header\">\n" + " </div>\n\n" + " <audio data-selector=\"customer-connected-audio\">\n" + " <source src=\"modules/remote-advisor-agent/assets/audio/incomingCall.mp3\" type=\"audio/mp3\"/>\n" + " </audio>\n\n" + "<div class=\"col9\">\n" + " <div class=\"declaration-image-div\">{>pp-svg-image:no-products-other-bank imageId=\"declaration-image\" source=\"./assets/images/life-insurance-contract/cuestionario_riesgos.svg\"/}</div>\n" + " <p class=\"h5 clr-dark-gray lic-declaration-remark\">{lic-risk-declaration-remark|s}</p>\n" + " </div>\n\n" + " <div data-region-id=\"login-dnie-image\" class=\"login-dnie-image\"><img src=\"assets/images/dni-logo.png\"/></div>"; final Pattern pattern = Pattern.compile(regex, Pattern.CASE_INSENSITIVE); 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