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

/
/
gm

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 = "<a\\s+.*?href=\"https:\\/\\/code.amazon.com\\/packages\\/AWSBrewPricingPlcConsole\\/releases\\/(\\d+)\\.(\\d+)\\.(\\d+)\\.(\\d+)"; final String string = "\n\n\n\n\n" + "<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01//EN\"\n" + " \"http://www.w3.org/TR/html4/strict.dtd\">\n" + "<html>\n\n" + "<head>\n" + " <title>\n" + " AWSBrewPricingPlcConsole - Releases - Brazil Directory\n" + " </title>\n\n" + " \n\n" + "<!-- EXPERIMENTAL: Subject to change, don't rely on these -->\n" + "<meta name=\"environment\" content=\"DevCentralWebsite\">\n" + "<meta name=\"stage\" content=\"Prod\">\n" + "<!-- /EXPERIMENTAL -->\n\n\n" + " <link rel=\"stylesheet\"\n" + " type=\"text/css\"\n" + " href=\"https://internal-cdn.amazon.com/dtux.amazon.com/stylesheets/dtux-style.css\">\n\n" + " <link href=\"https://internal-cdn.amazon.com/devcentral.amazon.com/style/helptips.css\"\n" + " rel=\"stylesheet\"\n" + " type=\"text/css\">\n\n" + " <link rel=\"icon\"\n" + " href=\"https://internal-cdn.amazon.com/devcentral.amazon.com/images/brazil.ico\"\n" + " type=\"image/x-icon\">\n" + " <link rel=\"shortcut icon\"\n" + " href=\"https://internal-cdn.amazon.com/devcentral.amazon.com/images/brazil.ico\"\n" + " type=\"image/x-icon\">\n\n" + " <link rel=\"stylesheet\"\n" + " type=\"text/css\"\n" + " href=\"https://internal-cdn.amazon.com/btk.amazon.com/ajax/libs/jquery/plugins/autocomplete/1.1/jquery.autocomplete.min.css\">\n\n" + " <link href=\"https://internal-cdn.amazon.com/devcentral.amazon.com/brazil/directory/stylesheet.min.css?size=24097\"\n" + " rel=\"stylesheet\"\n" + " type=\"text/css\">\n\n" + " <link rel=\"stylesheet\" type=\"text/css\" href=\"https://internal-cdn.amazon.com/devcentral.amazon.com/brazil/directory/visualizer/stylesheets/visualizer.min.css?size=1088\" >\n\n" + " <link rel=\"stylesheet\"\n" + " type=\"text/css\"\n" + " href=\"https://internal-cdn.amazon.com/is-it-down.amazon.com/stylesheets/stripe.css\">\n\n" + " <script type=\"text/javascript\"\n" + " src=\"https://internal-cdn.amazon.com/btk.amazon.com/ajax/libs/jquery/1.7.2/jquery.min.js\"></script>\n" + " <script type=\"text/javascript\"\n" + " src=\"https://internal-cdn.amazon.com/dtux.amazon.com/javascripts/cache/dtux-style.js\"></script>\n" + " <script type=\"text/javascript\"\n" + " src=\"https://internal-cdn.amazon.com/btk.amazon.com/ajax/libs/jquery/plugins/autocomplete/1.1/jquery.autocomplete.min.js\"></script>\n" + " <script type=\"text/javascript\"\n" + " src=\"https://internal-cdn.amazon.com/btk.amazon.com/ajax/libs/jquery/plugins/tablesorter/2.0.3/jquery.tablesorter.min.js\"></script>\n\n" + " <script type=\"text/javascript\"\n" + " src=\"https://internal-cdn.amazon.com/devcentral.amazon.com/brazil/directory/script.min.js?size=2302\">\n" + " </script>\n\n" + " <script type=\"text/javascript\">\n" + " IS_PROD = true;\n" + " REMOTE_USER = 'vladyang';\n" + " </script>\n\n" + "</head>\n\n" + "<body>\n" + "<div id=\"content\">\n" + " <div class=\"inner-container\">\n\n" + " <div class=\"indexHeader\">\n" + " <span class='titleBarTitle'>\n" + " \n" + "<a href=\"/\">devcentral</a> &gt;\n\n" + " <a href=\"https://devcentral.amazon.com/ac/brazil/directory/\">brazil directory</a>\n" + " &gt; \n" + " <a href=\"https://devcentral.amazon.com/ac/brazil/directory/packages/by-owner\">packages</a> &gt; <a href=\"https://devcentral.amazon.com/ac/brazil/directory/package/overview/AWSBrewPricingPlcConsole\">AWSBrewPricingPlcConsole</a> &gt; <a href=\"https://devcentral.amazon.com/ac/brazil/directory/package/majorVersionSummary/AWSBrewPricingPlcConsole?majorVersion=1.3\">1.3</a> &gt; release notes\n\n" + " </span>\n" + " </div>\n\n" + " <div class='titleBarHelper'>\n" + " \n" + " <div id=\"searchBoxes\">\n" + " \n" + " \n" + " <form action=\"https://devcentral.amazon.com/ac/brazil/directory/packages/search\"\n" + " id=\"findPackageForm\">\n" + " <div>\n" + " Search Packages:\n" + " <input type=\"text\" id=\"findPackage\" name=\"q\">\n" + " </div>\n" + " </form>\n\n" + " \n" + " \n" + " <form action=\"https://devcentral.amazon.com/ac/brazil/directory/version-sets/search\"\n" + " id=\"findVersionSetForm\">\n" + " <div>\n" + " Search Version Sets:\n" + " <input type=\"text\"\n" + " id=\"findVersionSet\"\n" + " class=\"versionSetInput\"\n" + " name=\"q\"\n" + " value=\"live\">\n" + " </div>\n" + " </form>\n\n" + " </div>\n\n" + " </div>\n\n" + " <h1>Package: AWSBrewPricingPlcConsole</h1>\n\n" + " \n" + " \n\n" + "<!--\n" + "Timing for addPackageToRoute (in seconds):\n" + "{\n" + " 'getBranchByPackageAndName' => '0.0113730430603027',\n" + " 'getPackageSynopsisByName' => '0.0839250087738037'\n" + "}\n\n" + "-->\n\n" + "<div id=\"viewInLinks\">\n" + "View in\n" + " <a href=\"/brazil/go/src-control?pkg=AWSBrewPricingPlcConsole\">Code Browser</a>\n" + " |\n" + " <a href=\"https://omni-grok.amazon.com/s?path=/AWSBrewPricingPlcConsole&indexName=GitFarm_6\">OmniGrok</a>\n\n" + " |\n" + " <a href=\"https://apollo.amazon.com/package.html?packageName=AWSBrewPricingPlcConsole&amp;showEnvironmentUsage=1\">\n" + " Apollo\n" + " </a>\n" + "</div>\n\n\n" + " <div id=\"headerWarning\">\n" + " \n\n" + " </div>\n\n" + " <div id=\"flash\">\n" + " \n" + " \n" + " \n\n\n" + " </div>\n\n" + " \n" + " \n" + " \n" + "<div class=\"tabs has-subnav\">\n" + "<ul>\n" + " <li class=\"tab \"><a class=\" \"\n" + " href=\"https://devcentral.amazon.com/ac/brazil/directory/package/overview/AWSBrewPricingPlcConsole\">Overview</a></li>\n" + " <li class=\"tab \"><a class=\" \"\n" + " href=\"https://devcentral.amazon.com/ac/brazil/directory/package/branches/AWSBrewPricingPlcConsole\">Branches</a></li>\n" + " <li class=\"tab \"><a class=\" \"\n" + " href=\"https://devcentral.amazon.com/ac/brazil/directory/package/releases/AWSBrewPricingPlcConsole\">All Releases</a></li>\n" + " <li class=\"tab \"><a class=\" \"\n" + " href=\"https://devcentral.amazon.com/ac/brazil/directory/package/sourceGuidance/AWSBrewPricingPlcConsole\">Source Guidance</a></li>\n" + " <li class=\"tab active\"><a class=\"active vendor-guidance-NONE\"\n" + " href=\"https://devcentral.amazon.com/ac/brazil/directory/package/majorVersionSummary/AWSBrewPricingPlcConsole?majorVersion=1.3\">1.3 </a></li>\n" + " <li class=\"tab \"><a class=\" vendor-guidance-NONE\"\n" + " href=\"https://devcentral.amazon.com/ac/brazil/directory/package/majorVersionSummary/AWSBrewPricingPlcConsole?majorVersion=1.0\">1.0 </a></li>\n" + "</ul>\n" + "</div>\n\n" + " \n" + " \n" + "<div class=\"subtabs\">\n" + "<ul>\n" + " <li class=\"subtab \"><a class=\" \"\n" + " href=\"https://devcentral.amazon.com/ac/brazil/directory/package/majorVersionSummary/AWSBrewPricingPlcConsole?majorVersion=1.3\">Summary</a></li>\n" + " <li class=\"subtab active\"><a class=\"active \"\n" + " href=\"https://devcentral.amazon.com/ac/brazil/directory/package/notes/AWSBrewPricingPlcConsole?majorVersion=1.3\">Releases</a></li>\n" + " <li class=\"subtab \"><a class=\" \"\n" + " href=\"https://devcentral.amazon.com/ac/brazil/directory/package/deps/AWSBrewPricingPlcConsole?direction=down&majorVersion=1.3&graphType=runtime_dependencies-resolved\">Dependencies</a></li>\n" + " <li class=\"subtab \"><a class=\" \"\n" + " href=\"https://devcentral.amazon.com/ac/brazil/directory/package/deps/AWSBrewPricingPlcConsole?direction=up&majorVersion=1.3\">Consumers</a></li>\n" + "</ul>\n" + "</div>\n\n\n\n\n" + " <div class='underNav'>\n" + " <div class=\"subNavHolder\">\n\n\n\n\n\n\n\n\n\n" + "<div id=\"actions\">\n" + " <h3>Package Actions</h3>\n\n\n" + " \n" + "<form method=\"get\"\n" + " action=\"/brazil/packages/versionDiff/\">\n" + " <div>\n" + " <input type=\"hidden\" name=\"packageName\" value=\"AWSBrewPricingPlcConsole\">\n" + " <button type=\"submit\">\n" + " Diff <b>Versions</b>\n" + " </button>\n" + " </div>\n" + "</form>\n\n" + "</div>\n" + " \n\n\n\n\n\n\n\n\n" + "<h2>Releases</h2>\n\n" + "<div class=\"releaseNotes\">\n" + "<table class=\"releaseNotes\">\n" + " <tr>\n" + " <td class=\"version\">\n" + " <a name=\"1.3.3.0\"></a><a href=\"https://code.amazon.com/packages/AWSBrewPricingPlcConsole/releases/1.3.3.0\"><b>1.3</b>.3.0</a>\n" + " </td>\n" + " <td class=\"nowrap\">Tue Jan 8 01:39:08 2019</td>\n" + " <td>\n" + " AWSBrewPricingPlcConsole/<a href=\"/brazil/go/src-control?branch=mainline&pkg=AWSBrewPricingPlcConsole\">mainline</a>@<a href=\"/brazil/go/src-control?branch=mainline&cln=6a10a7b2e3108941009efcfaef877b0df6a4063a&pkg=AWSBrewPricingPlcConsole\">6a10a7b2e3108941009efcfaef877b0df6a4063a</a>&nbsp;(GitFarm)\n" + " </td>\n" + " <td>\n" + " <a href=\"https://devcentral.amazon.com/ac/brazil/directory/version-set/overview/AWSBrewPricingPlcTools/AWSBrewPricingPlcConsole\">AWSBrewPricingPlcTools/AWSBrewPricingPlcConsole</a>\n" + " </td>\n" + " <td style=\"width: 50%\">\n" + " Built in <a href=\"https://build.amazon.com/2058367784\">request 2058367784</a>\n" + " </td>\n\n" + " </tr>\n" + " <tr>\n" + " <td colspan=\"5\" class=\"text\">\n" + " <div style=\"overflow: auto\">\n" + " Requester: vladyang<br>\n" + " [Change 6a10a7b2e3108941009efcfaef877b0df6a4063a by vladyang] adding version info<br>\n" + "<br>\n\n" + " </div>\n" + " </td>\n" + " </tr>\n" + " <tr>\n" + " <td class=\"version\">\n" + " <a name=\"1.3.2.0\"></a><a href=\"https://code.amazon.com/packages/AWSBrewPricingPlcConsole/releases/1.3.2.0\"><b>1.3</b>.2.0</a>\n" + " </td>\n" + " <td class=\"nowrap\">Tue Jan 8 01:20:29 2019</td>\n" + " <td>\n" + " AWSBrewPricingPlcConsole/<a href=\"/brazil/go/src-control?branch=mainline&pkg=AWSBrewPricingPlcConsole\">mainline</a>@<a href=\"/brazil/go/src-control?branch=mainline&cln=3d728050bff78d98870ca70662e62bebbfa91f48&pkg=AWSBrewPricingPlcConsole\">3d728050bff78d98870ca70662e62bebbfa91f48</a>&nbsp;(GitFarm)\n" + " </td>\n" + " <td>\n" + " <a href=\"https://devcentral.amazon.com/ac/brazil/directory/version-set/overview/AWSBrewPricingPlcTools/AWSBrewPricingPlcConsole\">AWSBrewPricingPlcTools/AWSBrewPricingPlcConsole</a>\n" + " </td>\n" + " <td style=\"width: 50%\">\n" + " Built in <a href=\"https://build.amazon.com/2058362893\">request 2058362893</a>\n" + " </td>\n\n" + " </tr>\n" + " <tr>\n" + " <td colspan=\"5\" class=\"text\">\n" + " <div style=\"overflow: auto\">\n" + " Requester: vladyang<br>\n" + " [3d72805 by vladyang] Initial Test Set\n" + " </div>\n" + " </td>\n" + " </tr>\n" + " <tr>\n" + " <td class=\"version\">\n" + " <a name=\"1.3.1.0\"></a><a href=\"https://code.amazon.com/packages/AWSBrewPricingPlcConsole/releases/1.3.1.0\"><b>1.3</b>.1.0</a>\n" + " </td>\n" + " <td class=\"nowrap\">Tue Jan 8 00:50:19 2019</td>\n" + " <td>\n" + " AWSBrewPricingPlcConsole/<a href=\"/brazil/go/src-control?branch=refactorings&pkg=AWSBrewPricingPlcConsole\">refactorings</a>@<a href=\"/brazil/go/src-control?branch=refactorings&cln=afcb73f4968c4fc6baf6beb85f8414ad1a2ab603&pkg=AWSBrewPricingPlcConsole\">afcb73f4968c4fc6baf6beb85f8414ad1a2ab603</a>&nbsp;(GitFarm)\n" + " </td>\n" + " <td>\n" + " <a href=\"https://devcentral.amazon.com/ac/brazil/directory/version-set/overview/AWSBrewPricingPlcTools/AWSBrewPricingPlcConsole\">AWSBrewPricingPlcTools/AWSBrewPricingPlcConsole</a>\n" + " </td>\n" + " <td style=\"width: 50%\">\n" + " Built in <a href=\"https://build.amazon.com/2058354122\">request 2058354122</a>\n" + " </td>\n\n" + " </tr>\n" + " <tr>\n" + " <td colspan=\"5\" class=\"text\">\n" + " <div style=\"overflow: auto\">\n" + " Requester: vladyang<br>\n" + " [afcb73f by vladyang] Fixing package versioning\n" + " </div>\n" + " </td>\n" + " </tr>\n" + "</table>\n" + "</div>\n\n" + "<a name=\"end\"></a>\n\n\n" + "<script type=\"text/javascript\"\n" + " src=\"https://internal-cdn.amazon.com/devcentral.amazon.com/brazil/directory/js/package.min.js?size=1292\"></script>\n\n\n\n\n" + " <div style=\"clear:both\"></div>\n" + " </div>\n" + " </div>\n" + " </div>\n" + "</div>\n\n" + " <div id='footer'>\n" + " <div class='column'>\n" + " <h3>Packages</h3>\n" + " <ul>\n" + " <li><a href=\"https://octane.amazon.com/package\">Create Package</a></li>\n" + " <li><a href=\"/brazil/packages\">Third Party Packages</a></li>\n" + " <li><a href=\"https://code.amazon.com/packages/find_by_team_for_user\">Packages By Owner</a></li>\n" + " <li><a href=\"/ac/brazil/directory/packages/prune-list\">Pruned Packages</a></li>\n" + " </ul>\n" + " </div>\n" + " <div class='column'>\n" + " <h3>Version Sets</h3>\n" + " <ul>\n" + " <li><a href=\"https://code.amazon.com/version-sets/new\">Create</a></li>\n" + " <li><a href=\"https://code.amazon.com/version-sets/\">Browse</a></li>\n" + " </ul>\n" + " </div>\n" + " <div class='business_card'>\n" + " <h3>Need help?</h3>\n" + " <ul>\n" + " <li><a href=\"https://w.amazon.com/index.php/BuilderTools/Product/Brazil_Package_Directory\">Package Directory Documentation</a></li>\n" + " <li><a href=\"https://i.amazon.com/issues/create?assignedFolder=27de5d2d-8357-4fe4-9344-7f9d95d94d6b&descriptionContentType=text%2Famz-markdown-sim&extensions%5Btt%5D%5Bimpact%5D=4\">Submit an Issue (problems or suggestions)</a></li>\n" + " <li><a href=\"https://w.amazon.com/index.php/BuilderTools/OfficeHours\">Office Hours</a></li>\n" + " </ul>\n" + " <div class=\"browser_support\">\n" + " <a href=\"https://w.amazon.com/?BuilderTools/Browser_Support_Policy\">Browser Support Policy</a>\n" + " </div>\n" + " </div>\n" + " </div>\n\n" + " \n" + "<script type=\"text/javascript\" src=\"https://internal-cdn.amazon.com/devcentral.amazon.com/js/display.min.js?size=582\"></script>\n\n\n" + " <script type=\"text/javascript\" src=\"https://internal-cdn.amazon.com/is-it-down.amazon.com/javascripts/stripe.min.js\"></script>\n" + " <script type=\"text/javascript\">\n" + " // \"Is It Down?\" Stripe for Package Builder\n" + " isItDownStripe(\"brazil\", 2, 1);\n" + " </script>\n\n" + " </body>\n" + "</html>\n\n\n\n"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE); 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