output/getting-started/exclude-parameters.html - struts-site - Git at Google

 <!DOCTYPE html>
 <html lang="en">
 <head>
   <meta charset="UTF-8"/>
   <meta name="viewport" content="width=device-width, initial-scale=1.0"/>
   <meta name="Date-Revision-yyyymmdd" content="20140918"/>
   <meta http-equiv="Content-Language" content="en"/>
   <meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1">

   <title>Exclude parameters</title>

   <link href="//fonts.googleapis.com/css?family=Source+Sans+Pro:300,400,600,700,400italic,600italic,700italic" rel="stylesheet" type="text/css">
   <link href="//netdna.bootstrapcdn.com/font-awesome/4.0.3/css/font-awesome.css" rel="stylesheet">
   <link href="/css/main.css" rel="stylesheet">
   <link href="/css/custom.css" rel="stylesheet">
   <link href="/css/syntax.css" rel="stylesheet">

   <script src="//code.jquery.com/jquery-1.11.0.min.js"></script>
   <script type="text/javascript" src="/bootstrap/js/bootstrap.js"></script>
   <script type="text/javascript" src="/js/community.js"></script>

   <!-- Matomo -->
   <script>
     var _paq = window._paq = window._paq || [];
     /* tracker methods like "setCustomDimension" should be called before "trackPageView" */
     /* We explicitly disable cookie tracking to avoid privacy issues */
     _paq.push(['disableCookies']);
     _paq.push(['trackPageView']);
     _paq.push(['enableLinkTracking']);
     (function() {
       var u="//analytics.apache.org/";
       _paq.push(['setTrackerUrl', u+'matomo.php']);
       _paq.push(['setSiteId', '41']);
       var d=document, g=d.createElement('script'), s=d.getElementsByTagName('script')[0];
       g.async=true; g.src=u+'matomo.js'; s.parentNode.insertBefore(g,s);
     })();
   </script>
   <!-- End Matomo Code -->
 </head>
 <body>

 <a href="https://github.com/apache/struts" class="github-ribbon">
   <img decoding="async" loading="lazy" style="position: absolute; right: 0; border: 0;" width="149" height="149" src="https://github.blog/wp-content/uploads/2008/12/forkme_right_red_aa0000.png?resize=149%2C149" class="attachment-full size-full" alt="Fork me on GitHub" data-recalc-dims="1">
 </a>

 <header>
   <nav>
     <div role="navigation" class="navbar navbar-default navbar-fixed-top">
       <div class="container">
         <div class="navbar-header">
           <button type="button" data-toggle="collapse" data-target="#struts-menu" class="navbar-toggle">
             Menu
             <span class="sr-only">Toggle navigation</span>
             <span class="icon-bar"></span>
             <span class="icon-bar"></span>
             <span class="icon-bar"></span>
           </button>
           <a href="/index.html" class="navbar-brand logo"><img src="/img/struts-logo.svg"></a>
         </div>
         <div id="struts-menu" class="navbar-collapse collapse">
           <ul class="nav navbar-nav">
             <li class="dropdown">
               <a data-toggle="dropdown" href="#" class="dropdown-toggle">
                 Home<b class="caret"></b>
               </a>
               <ul class="dropdown-menu">
                 <li><a href="/index.html">Welcome</a></li>
                 <li><a href="/download.cgi">Download</a></li>
                 <li><a href="/releases.html">Releases</a></li>
                 <li><a href="/announce-2023.html">Announcements</a></li>
                 <li><a href="http://www.apache.org/licenses/">License</a></li>
                 <li><a href="https://www.apache.org/foundation/thanks.html">Thanks!</a></li>
                 <li><a href="https://www.apache.org/foundation/sponsorship.html">Sponsorship</a></li>
                 <li><a href="https://privacy.apache.org/policies/privacy-policy-public.html">Privacy Policy</a></li>
               </ul>
             </li>
             <li class="dropdown">
               <a data-toggle="dropdown" href="#" class="dropdown-toggle">
                 Support<b class="caret"></b>
               </a>
               <ul class="dropdown-menu">
                 <li><a href="/mail.html">User Mailing List</a></li>
                 <li><a href="https://issues.apache.org/jira/browse/WW">Issue Tracker</a></li>
                 <li><a href="/security.html">Reporting Security Issues</a></li>
                 <li><a href="/commercial-support.html">Commercial Support</a></li>
                 <li class="divider"></li>
                 <li><a href="https://cwiki.apache.org/confluence/display/WW/Migration+Guide">Version Notes</a></li>
                 <li><a href="https://cwiki.apache.org/confluence/display/WW/Security+Bulletins">Security Bulletins</a></li>
                 <li class="divider"></li>
                 <li><a href="/maven/project-info.html">Maven Project Info</a></li>
                 <li><a href="/maven/struts2-core/dependencies.html">Struts Core Dependencies</a></li>
                 <li><a href="/maven/struts2-plugins/modules.html">Plugin Dependencies</a></li>
               </ul>
             </li>
             <li class="dropdown">
               <a data-toggle="dropdown" href="#" class="dropdown-toggle">
                 Documentation<b class="caret"></b>
               </a>
               <ul class="dropdown-menu">
                 <li><a href="/birdseye.html">Birds Eye</a></li>
                 <li><a href="/primer.html">Key Technologies</a></li>
                 <li><a href="/kickstart.html">Kickstart FAQ</a></li>
                 <li><a href="https://cwiki.apache.org/confluence/display/WW/Home">Wiki</a></li>
                 <li class="divider"></li>
                 <li><a href="/getting-started/">Getting Started</a></li>
                 <li><a href="/security/">Security Guide</a></li>
                 <li><a href="/core-developers/">Core Developers Guide</a></li>
                 <li><a href="/tag-developers/">Tag Developers Guide</a></li>
                 <li><a href="/maven-archetypes/">Maven Archetypes</a></li>
                 <li><a href="/plugins/">Plugins</a></li>
                 <li><a href="/maven/struts2-core/apidocs/index.html">Struts Core API</a></li>
                 <li><a href="/tag-developers/tag-reference.html">Tag reference</a></li>
                 <li><a href="https://cwiki.apache.org/confluence/display/WW/FAQs">FAQs</a></li>
                 <li><a href="http://cwiki.apache.org/S2PLUGINS/home.html">Plugin registry</a></li>
               </ul>
             </li>
             <li class="dropdown">
               <a data-toggle="dropdown" href="#" class="dropdown-toggle">
                 Contributing<b class="caret"></b>
               </a>
               <ul class="dropdown-menu">
                 <li><a href="/youatstruts.html">You at Struts</a></li>
                 <li><a href="/helping.html">How to Help FAQ</a></li>
                 <li><a href="/dev-mail.html">Development Lists</a></li>
                 <li class="divider"></li>
                 <li><a href="/submitting-patches.html">Submitting patches</a></li>
                 <li><a href="/builds.html">Source Code and Builds</a></li>
                 <li><a href="/coding-standards.html">Coding standards</a></li>
                 <li><a href="/contributors/">Contributors Guide</a></li>
                 <li class="divider"></li>
                 <li><a href="/release-guidelines.html">Release Guidelines</a></li>
                 <li><a href="/bylaws.html">PMC Charter</a></li>
                 <li><a href="/volunteers.html">Volunteers</a></li>
                 <li><a href="https://gitbox.apache.org/repos/asf?p=struts.git">Source Repository</a></li>
                 <li><a href="/updating-website.html">Updating the website</a></li>
               </ul>
             </li>
             <li class="apache"><a href="http://www.apache.org/"><img src="/img/apache.png"></a></li>
           </ul>
         </div>
       </div>
     </div>
   </nav>
 </header>


 <article class="container">
   <section class="col-md-12">
     <a class="edit-on-gh" href="https://github.com/apache/struts-site/edit/master/source/getting-started/exclude-parameters.md" title="Edit this page on GitHub">Edit on GitHub</a>

     <a href="index.html" title="back to Getting started"><< back to Getting started</a>

     <h1 class="no_toc" id="exclude-parameters">Exclude Parameters</h1>

 <ul id="markdown-toc">
   <li><a href="#introduction" id="markdown-toc-introduction">Introduction</a></li>
   <li><a href="#processing-request-parameters" id="markdown-toc-processing-request-parameters">Processing Request Parameters</a></li>
   <li><a href="#excluding-request-parameters-from-struts-2-processing" id="markdown-toc-excluding-request-parameters-from-struts-2-processing">Excluding Request Parameters From Struts 2 Processing</a></li>
   <li><a href="#example-application" id="markdown-toc-example-application">Example Application</a></li>
   <li><a href="#summary" id="markdown-toc-summary">Summary</a></li>
 </ul>

 <p>The example code for this tutorial, <strong>exclude-parameters</strong>, is available at <a href="https://github.com/apache/struts-examples">struts-examples</a>.</p>

 <h2 id="introduction">Introduction</h2>

 <p>When <a href="../core-developers/struts-xml">Struts development mode is set to true</a> (also see <a href="debugging-struts">Debugging Struts</a>)
 the framework writes many informative messages to the log file. These messages include ones that indicate whether
 or not a specific parameter will be handled by the parameter interceptor and made available to the Action class.
 These log messages can be helpful in clearly identifying parameters that you do not want the parameter interceptor
 to process for security or other reasons. This article discusses how to exclude parameters from being handled by
 the parameter interceptor.</p>

 <p>The <a href="http://struts.apache.org/mail">Struts 2 user mailing list</a> is an excellent place to get help. If you are having
 a problem getting the tutorial example applications to work search the Struts 2 mailing list. If you don’t find an answer
 to your problem, post a question on the mailing list.</p>

 <h2 id="processing-request-parameters">Processing Request Parameters</h2>

 <p>Most request parameters are by default processed by the parameter interceptor and Struts 2 will attempt to modify the state
 of those Action class fields that match up to a parameter name by calling a corresponding public set method. For example
 if the request includes a parameter of lastName with a value of Phillips, Struts 2 will try to call a public method with
 a signature of setLastName(String lastName). However, there may be request parameters that you do not want Struts 2
 to try to set the value of in the Action class.</p>

 <p>Consider this code which creates a form:</p>

 <p><strong>Struts 2 Form Tags</strong></p>

 <div class="language-html highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="nt">&lt;s:form</span> <span class="na">action=</span><span class="s">"save"</span> <span class="na">method=</span><span class="s">"post"</span><span class="nt">&gt;</span>
     <span class="nt">&lt;s:textfield</span> <span class="na">key=</span><span class="s">"personBean.firstName"</span> <span class="nt">/&gt;</span>
     <span class="nt">&lt;s:textfield</span> <span class="na">key=</span><span class="s">"personBean.lastName"</span> <span class="nt">/&gt;</span>
     <span class="nt">&lt;s:textfield</span> <span class="na">key=</span><span class="s">"personBean.email"</span> <span class="nt">/&gt;</span>
     <span class="nt">&lt;s:textfield</span> <span class="na">key=</span><span class="s">"personBean.phoneNumber"</span> <span class="nt">/&gt;</span>
     <span class="nt">&lt;s:select</span> <span class="na">key=</span><span class="s">"personBean.sport"</span> <span class="na">list=</span><span class="s">"sports"</span> <span class="nt">/&gt;</span>
     <span class="nt">&lt;s:radio</span> <span class="na">key=</span><span class="s">"personBean.gender"</span> <span class="na">list=</span><span class="s">"genders"</span> <span class="nt">/&gt;</span>
     <span class="nt">&lt;s:select</span> <span class="na">key=</span><span class="s">"personBean.residency"</span> <span class="na">list=</span><span class="s">"states"</span> <span class="na">listKey=</span><span class="s">"stateAbbr"</span> <span class="na">listValue=</span><span class="s">"stateName"</span> <span class="nt">/&gt;</span>
     <span class="nt">&lt;s:checkbox</span> <span class="na">key=</span><span class="s">"personBean.over21"</span> <span class="nt">/&gt;</span>
     <span class="nt">&lt;s:checkboxlist</span> <span class="na">key=</span><span class="s">"personBean.carModels"</span> <span class="na">list=</span><span class="s">"carModelsAvailable"</span> <span class="nt">/&gt;</span>
     <span class="nt">&lt;s:submit</span> <span class="na">key=</span><span class="s">"submit"</span> <span class="nt">/&gt;</span>
 <span class="nt">&lt;/s:form&gt;</span>
 </code></pre></div></div>

 <p>The s:submit tag will create a submit button with a name of submit. Since the Action class probably doesn’t have
 a <code class="language-plaintext highlighter-rouge">setSubmit(String name)</code> method you will see the following log messages (only if Struts development mode is set to true):</p>

 <p><strong>Log Messages</strong></p>

 <div class="language-plaintext highlighter-rouge"><div class="highlight"><pre class="highlight"><code>Dec 31, 2012 3:43:53 PM
 com.opensymphony.xwork2.util.logging.commons.CommonsLogger warn
 WARNING: Parameter [submit] is not on the excludeParams list of patterns and will be appended to action!

 Dec 31, 2012 3:43:53 PM com.opensymphony.xwork2.util.logging.commons.CommonsLogger error
 SEVERE: Developer Notification (set struts.devMode to false to disable this message):
 Unexpected Exception caught setting 'submit' on 'class org.apache.struts.edit.action.EditAction: Error setting expression 'submit' with value ['Save Changes', ]
 </code></pre></div></div>

 <h2 id="excluding-request-parameters-from-struts-2-processing">Excluding Request Parameters From Struts 2 Processing</h2>

 <p>If you’re not familiar with setting up a custom interceptor stack for your Struts 2 application review <a href="introducing-interceptors">Introducing Interceptors</a>.</p>

 <p>To exclude specific parameters from being processed by the Struts 2 framework you need to add those parameter names
 to the list of excluded parameters. One way to do this is by adding those parameter names to the collection of <code class="language-plaintext highlighter-rouge">excludedParams</code>
 for the Parameters interceptor. You can do this by modifying the Parameters interceptor in setting up the stack of interceptors
 used by your Struts 2 application. For example:</p>

 <p><strong>Setup Interceptor Stack To Exclude submit Parameter</strong></p>

 <div class="language-xml highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="nt">&lt;interceptors&gt;</span>
     <span class="nt">&lt;interceptor-stack</span> <span class="na">name=</span><span class="s">"appDefault"</span><span class="nt">&gt;</span>
         <span class="nt">&lt;interceptor-ref</span> <span class="na">name=</span><span class="s">"defaultStack"</span><span class="nt">&gt;</span>
             <span class="nt">&lt;param</span> <span class="na">name=</span><span class="s">"exception.logEnabled"</span><span class="nt">&gt;</span>true<span class="nt">&lt;/param&gt;</span>
             <span class="nt">&lt;param</span> <span class="na">name=</span><span class="s">"exception.logLevel"</span><span class="nt">&gt;</span>ERROR<span class="nt">&lt;/param&gt;</span>
             <span class="nt">&lt;param</span> <span class="na">name=</span><span class="s">"params.excludeParams"</span><span class="nt">&gt;</span>dojo..*,^struts..*,^session..*,^request..*,^application..*,^servlet(Request|Response)..*,parameters...*,submit<span class="nt">&lt;/param&gt;</span>
         <span class="nt">&lt;/interceptor-ref&gt;</span>
     <span class="nt">&lt;/interceptor-stack&gt;</span>
 <span class="nt">&lt;/interceptors&gt;</span>

 <span class="nt">&lt;default-interceptor-ref</span> <span class="na">name=</span><span class="s">"appDefault"</span> <span class="nt">/&gt;</span>
 </code></pre></div></div>

 <p>The value of node <code class="language-plaintext highlighter-rouge">&lt;param name="params.excludeParams"&gt;</code> is a comma-delimited list of regular expressions or simple
 Strings that identify request parameters that should NOT be processed by the Parameters interceptor. To exclude
 the <code class="language-plaintext highlighter-rouge">submit</code> parameter (which is the name of the submit button in the form code above), I just added <code class="language-plaintext highlighter-rouge">submit</code> to the list.</p>

 <p>See the <a href="../core-developers/struts-default-xml">Basic Stack of Interceptors described here</a> to view the initial
 set of parameter names/regular expressions to exclude. Be sure to copy over the list of parameters already being excluded
 and then add your own parameters to the end separated by commas.</p>

 <h2 id="example-application">Example Application</h2>

 <p>Download the example application, <a href="https://github.com/apache/struts-examples/tree/master/exclude-parameters">exclude-params</a>
 that demonstrates excluding a request parameter. See the project’s README.txt file for how to build and run the application.</p>

 <p>To see the log messages written when not excluding the submit parameter remove the <code class="language-plaintext highlighter-rouge">,submit</code> from the list of excluded
 parameter values in the struts.xml file. Then rebuild and redeploy the application and view the console when running the application.</p>

 <h2 id="summary">Summary</h2>

 <p>It’s a nice feature of the Struts 2 framework that it logs during development which request parameters will and will not
 be processed. During development of a Struts 2 web application it’s a good practice to review these log messages to determine
 if there are any parameters that the framework should not process. For those parameters the Struts 2 framework should
 not process add the parameter name (or a regular expression that can be used to identify multiple parameter names)
 to the comma-delimited list that is the value for the <code class="language-plaintext highlighter-rouge">&lt;param name="params.excludeParams"&gt;</code> node.</p>

 <table>
   <tbody>
     <tr>
       <td>Return to <a href="preperable-interface">Preparable Interface</a></td>
       <td>or</td>
       <td>back to <a href="index">Getting started</a></td>
     </tr>
   </tbody>
 </table>

   </section>
 </article>


 <footer class="container">
   <div class="col-md-12">
     Copyright &copy; 2000-2022 <a href="https://www.apache.org/">The Apache Software Foundation</a>.
     Apache Struts, Struts, Apache, the Apache feather logo, and the Apache Struts project logos are
     trademarks of The Apache Software Foundation. All Rights Reserved.
   </div>
   <div class="col-md-12">Logo and website design donated by <a href="https://softwaremill.com/">SoftwareMill</a>.</div>
 </footer>

 <script>!function (d, s, id) {
   var js, fjs = d.getElementsByTagName(s)[0];
   if (!d.getElementById(id)) {
     js = d.createElement(s);
     js.id = id;
     js.src = "//platform.twitter.com/widgets.js";
     fjs.parentNode.insertBefore(js, fjs);
   }
 }(document, "script", "twitter-wjs");</script>
 <script src="https://apis.google.com/js/platform.js" async="async" defer="defer"></script>

 <div id="fb-root"></div>

 <script>(function (d, s, id) {
   var js, fjs = d.getElementsByTagName(s)[0];
   if (d.getElementById(id)) return;
   js = d.createElement(s);
   js.id = id;
   js.src = "//connect.facebook.net/en_GB/all.js#xfbml=1";
   fjs.parentNode.insertBefore(js, fjs);
 }(document, 'script', 'facebook-jssdk'));</script>


 </body>
 </html>
	<!DOCTYPE html>
	<html lang="en">
	<head>
	<meta charset="UTF-8"/>
	<meta name="viewport" content="width=device-width, initial-scale=1.0"/>
	<meta name="Date-Revision-yyyymmdd" content="20140918"/>
	<meta http-equiv="Content-Language" content="en"/>
	<meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1">

	<title>Exclude parameters</title>

	<link href="//fonts.googleapis.com/css?family=Source+Sans+Pro:300,400,600,700,400italic,600italic,700italic" rel="stylesheet" type="text/css">
	<link href="//netdna.bootstrapcdn.com/font-awesome/4.0.3/css/font-awesome.css" rel="stylesheet">
	<link href="/css/main.css" rel="stylesheet">
	<link href="/css/custom.css" rel="stylesheet">
	<link href="/css/syntax.css" rel="stylesheet">

	<script src="//code.jquery.com/jquery-1.11.0.min.js"></script>
	<script type="text/javascript" src="/bootstrap/js/bootstrap.js"></script>
	<script type="text/javascript" src="/js/community.js"></script>

	<!-- Matomo -->
	<script>
	var _paq = window._paq = window._paq \|\| [];
	/* tracker methods like "setCustomDimension" should be called before "trackPageView" */
	/* We explicitly disable cookie tracking to avoid privacy issues */
	_paq.push(['disableCookies']);
	_paq.push(['trackPageView']);
	_paq.push(['enableLinkTracking']);
	(function() {
	var u="//analytics.apache.org/";
	_paq.push(['setTrackerUrl', u+'matomo.php']);
	_paq.push(['setSiteId', '41']);
	var d=document, g=d.createElement('script'), s=d.getElementsByTagName('script')[0];
	g.async=true; g.src=u+'matomo.js'; s.parentNode.insertBefore(g,s);
	})();
	</script>
	<!-- End Matomo Code -->
	</head>
	<body>

	<a href="https://github.com/apache/struts" class="github-ribbon">
	<img decoding="async" loading="lazy" style="position: absolute; right: 0; border: 0;" width="149" height="149" src="https://github.blog/wp-content/uploads/2008/12/forkme_right_red_aa0000.png?resize=149%2C149" class="attachment-full size-full" alt="Fork me on GitHub" data-recalc-dims="1">
	</a>

	<header>
	<nav>
	<div role="navigation" class="navbar navbar-default navbar-fixed-top">
	<div class="container">
	<div class="navbar-header">
	<button type="button" data-toggle="collapse" data-target="#struts-menu" class="navbar-toggle">
	Menu
	<span class="sr-only">Toggle navigation</span>
	<span class="icon-bar"></span>
	<span class="icon-bar"></span>
	<span class="icon-bar"></span>
	</button>
	<a href="/index.html" class="navbar-brand logo"><img src="/img/struts-logo.svg"></a>
	</div>
	<div id="struts-menu" class="navbar-collapse collapse">
	<ul class="nav navbar-nav">
	<li class="dropdown">
	<a data-toggle="dropdown" href="#" class="dropdown-toggle">
	Home<b class="caret"></b>
	</a>
	<ul class="dropdown-menu">
	<li><a href="/index.html">Welcome</a></li>
	<li><a href="/download.cgi">Download</a></li>
	<li><a href="/releases.html">Releases</a></li>
	<li><a href="/announce-2023.html">Announcements</a></li>
	<li><a href="http://www.apache.org/licenses/">License</a></li>
	<li><a href="https://www.apache.org/foundation/thanks.html">Thanks!</a></li>
	<li><a href="https://www.apache.org/foundation/sponsorship.html">Sponsorship</a></li>
	<li><a href="https://privacy.apache.org/policies/privacy-policy-public.html">Privacy Policy</a></li>
	</ul>
	</li>
	<li class="dropdown">
	<a data-toggle="dropdown" href="#" class="dropdown-toggle">
	Support<b class="caret"></b>
	</a>
	<ul class="dropdown-menu">
	<li><a href="/mail.html">User Mailing List</a></li>
	<li><a href="https://issues.apache.org/jira/browse/WW">Issue Tracker</a></li>
	<li><a href="/security.html">Reporting Security Issues</a></li>
	<li><a href="/commercial-support.html">Commercial Support</a></li>
	<li class="divider"></li>
	<li><a href="https://cwiki.apache.org/confluence/display/WW/Migration+Guide">Version Notes</a></li>
	<li><a href="https://cwiki.apache.org/confluence/display/WW/Security+Bulletins">Security Bulletins</a></li>
	<li class="divider"></li>
	<li><a href="/maven/project-info.html">Maven Project Info</a></li>
	<li><a href="/maven/struts2-core/dependencies.html">Struts Core Dependencies</a></li>
	<li><a href="/maven/struts2-plugins/modules.html">Plugin Dependencies</a></li>
	</ul>
	</li>
	<li class="dropdown">
	<a data-toggle="dropdown" href="#" class="dropdown-toggle">
	Documentation<b class="caret"></b>
	</a>
	<ul class="dropdown-menu">
	<li><a href="/birdseye.html">Birds Eye</a></li>
	<li><a href="/primer.html">Key Technologies</a></li>
	<li><a href="/kickstart.html">Kickstart FAQ</a></li>
	<li><a href="https://cwiki.apache.org/confluence/display/WW/Home">Wiki</a></li>
	<li class="divider"></li>
	<li><a href="/getting-started/">Getting Started</a></li>
	<li><a href="/security/">Security Guide</a></li>
	<li><a href="/core-developers/">Core Developers Guide</a></li>
	<li><a href="/tag-developers/">Tag Developers Guide</a></li>
	<li><a href="/maven-archetypes/">Maven Archetypes</a></li>
	<li><a href="/plugins/">Plugins</a></li>
	<li><a href="/maven/struts2-core/apidocs/index.html">Struts Core API</a></li>
	<li><a href="/tag-developers/tag-reference.html">Tag reference</a></li>
	<li><a href="https://cwiki.apache.org/confluence/display/WW/FAQs">FAQs</a></li>
	<li><a href="http://cwiki.apache.org/S2PLUGINS/home.html">Plugin registry</a></li>
	</ul>
	</li>
	<li class="dropdown">
	<a data-toggle="dropdown" href="#" class="dropdown-toggle">
	Contributing<b class="caret"></b>
	</a>
	<ul class="dropdown-menu">
	<li><a href="/youatstruts.html">You at Struts</a></li>
	<li><a href="/helping.html">How to Help FAQ</a></li>
	<li><a href="/dev-mail.html">Development Lists</a></li>
	<li class="divider"></li>
	<li><a href="/submitting-patches.html">Submitting patches</a></li>
	<li><a href="/builds.html">Source Code and Builds</a></li>
	<li><a href="/coding-standards.html">Coding standards</a></li>
	<li><a href="/contributors/">Contributors Guide</a></li>
	<li class="divider"></li>
	<li><a href="/release-guidelines.html">Release Guidelines</a></li>
	<li><a href="/bylaws.html">PMC Charter</a></li>
	<li><a href="/volunteers.html">Volunteers</a></li>
	<li><a href="https://gitbox.apache.org/repos/asf?p=struts.git">Source Repository</a></li>
	<li><a href="/updating-website.html">Updating the website</a></li>
	</ul>
	</li>
	<li class="apache"><a href="http://www.apache.org/"><img src="/img/apache.png"></a></li>
	</ul>
	</div>
	</div>
	</div>
	</nav>
	</header>


	<article class="container">
	<section class="col-md-12">
	<a class="edit-on-gh" href="https://github.com/apache/struts-site/edit/master/source/getting-started/exclude-parameters.md" title="Edit this page on GitHub">Edit on GitHub</a>

	<a href="index.html" title="back to Getting started"><< back to Getting started</a>

	<h1 class="no_toc" id="exclude-parameters">Exclude Parameters</h1>

	<ul id="markdown-toc">
	<li><a href="#introduction" id="markdown-toc-introduction">Introduction</a></li>
	<li><a href="#processing-request-parameters" id="markdown-toc-processing-request-parameters">Processing Request Parameters</a></li>
	<li><a href="#excluding-request-parameters-from-struts-2-processing" id="markdown-toc-excluding-request-parameters-from-struts-2-processing">Excluding Request Parameters From Struts 2 Processing</a></li>
	<li><a href="#example-application" id="markdown-toc-example-application">Example Application</a></li>
	<li><a href="#summary" id="markdown-toc-summary">Summary</a></li>
	</ul>

	<p>The example code for this tutorial, <strong>exclude-parameters</strong>, is available at <a href="https://github.com/apache/struts-examples">struts-examples</a>.</p>

	<h2 id="introduction">Introduction</h2>

	<p>When <a href="../core-developers/struts-xml">Struts development mode is set to true</a> (also see <a href="debugging-struts">Debugging Struts</a>)
	the framework writes many informative messages to the log file. These messages include ones that indicate whether
	or not a specific parameter will be handled by the parameter interceptor and made available to the Action class.
	These log messages can be helpful in clearly identifying parameters that you do not want the parameter interceptor
	to process for security or other reasons. This article discusses how to exclude parameters from being handled by
	the parameter interceptor.</p>

	<p>The <a href="http://struts.apache.org/mail">Struts 2 user mailing list</a> is an excellent place to get help. If you are having
	a problem getting the tutorial example applications to work search the Struts 2 mailing list. If you don’t find an answer
	to your problem, post a question on the mailing list.</p>

	<h2 id="processing-request-parameters">Processing Request Parameters</h2>

	<p>Most request parameters are by default processed by the parameter interceptor and Struts 2 will attempt to modify the state
	of those Action class fields that match up to a parameter name by calling a corresponding public set method. For example
	if the request includes a parameter of lastName with a value of Phillips, Struts 2 will try to call a public method with
	a signature of setLastName(String lastName). However, there may be request parameters that you do not want Struts 2
	to try to set the value of in the Action class.</p>

	<p>Consider this code which creates a form:</p>

	<p><strong>Struts 2 Form Tags</strong></p>

	<div class="language-html highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="nt"><s:form</span> <span class="na">action=</span><span class="s">"save"</span> <span class="na">method=</span><span class="s">"post"</span><span class="nt">></span>
	<span class="nt"><s:textfield</span> <span class="na">key=</span><span class="s">"personBean.firstName"</span> <span class="nt">/></span>
	<span class="nt"><s:textfield</span> <span class="na">key=</span><span class="s">"personBean.lastName"</span> <span class="nt">/></span>
	<span class="nt"><s:textfield</span> <span class="na">key=</span><span class="s">"personBean.email"</span> <span class="nt">/></span>
	<span class="nt"><s:textfield</span> <span class="na">key=</span><span class="s">"personBean.phoneNumber"</span> <span class="nt">/></span>
	<span class="nt"><s:select</span> <span class="na">key=</span><span class="s">"personBean.sport"</span> <span class="na">list=</span><span class="s">"sports"</span> <span class="nt">/></span>
	<span class="nt"><s:radio</span> <span class="na">key=</span><span class="s">"personBean.gender"</span> <span class="na">list=</span><span class="s">"genders"</span> <span class="nt">/></span>
	<span class="nt"><s:select</span> <span class="na">key=</span><span class="s">"personBean.residency"</span> <span class="na">list=</span><span class="s">"states"</span> <span class="na">listKey=</span><span class="s">"stateAbbr"</span> <span class="na">listValue=</span><span class="s">"stateName"</span> <span class="nt">/></span>
	<span class="nt"><s:checkbox</span> <span class="na">key=</span><span class="s">"personBean.over21"</span> <span class="nt">/></span>
	<span class="nt"><s:checkboxlist</span> <span class="na">key=</span><span class="s">"personBean.carModels"</span> <span class="na">list=</span><span class="s">"carModelsAvailable"</span> <span class="nt">/></span>
	<span class="nt"><s:submit</span> <span class="na">key=</span><span class="s">"submit"</span> <span class="nt">/></span>
	<span class="nt"></s:form></span>
	</code></pre></div></div>

	<p>The s:submit tag will create a submit button with a name of submit. Since the Action class probably doesn’t have
	a <code class="language-plaintext highlighter-rouge">setSubmit(String name)</code> method you will see the following log messages (only if Struts development mode is set to true):</p>

	<p><strong>Log Messages</strong></p>

	<div class="language-plaintext highlighter-rouge"><div class="highlight"><pre class="highlight"><code>Dec 31, 2012 3:43:53 PM
	com.opensymphony.xwork2.util.logging.commons.CommonsLogger warn
	WARNING: Parameter [submit] is not on the excludeParams list of patterns and will be appended to action!

	Dec 31, 2012 3:43:53 PM com.opensymphony.xwork2.util.logging.commons.CommonsLogger error
	SEVERE: Developer Notification (set struts.devMode to false to disable this message):
	Unexpected Exception caught setting 'submit' on 'class org.apache.struts.edit.action.EditAction: Error setting expression 'submit' with value ['Save Changes', ]
	</code></pre></div></div>

	<h2 id="excluding-request-parameters-from-struts-2-processing">Excluding Request Parameters From Struts 2 Processing</h2>

	<p>If you’re not familiar with setting up a custom interceptor stack for your Struts 2 application review <a href="introducing-interceptors">Introducing Interceptors</a>.</p>

	<p>To exclude specific parameters from being processed by the Struts 2 framework you need to add those parameter names
	to the list of excluded parameters. One way to do this is by adding those parameter names to the collection of <code class="language-plaintext highlighter-rouge">excludedParams</code>
	for the Parameters interceptor. You can do this by modifying the Parameters interceptor in setting up the stack of interceptors
	used by your Struts 2 application. For example:</p>

	<p><strong>Setup Interceptor Stack To Exclude submit Parameter</strong></p>

	<div class="language-xml highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="nt"><interceptors></span>
	<span class="nt"><interceptor-stack</span> <span class="na">name=</span><span class="s">"appDefault"</span><span class="nt">></span>
	<span class="nt"><interceptor-ref</span> <span class="na">name=</span><span class="s">"defaultStack"</span><span class="nt">></span>
	<span class="nt"><param</span> <span class="na">name=</span><span class="s">"exception.logEnabled"</span><span class="nt">></span>true<span class="nt"></param></span>
	<span class="nt"><param</span> <span class="na">name=</span><span class="s">"exception.logLevel"</span><span class="nt">></span>ERROR<span class="nt"></param></span>
	<span class="nt"><param</span> <span class="na">name=</span><span class="s">"params.excludeParams"</span><span class="nt">></span>dojo..,^struts..,^session..,^request..,^application..,^servlet(Request\|Response)..,parameters...*,submit<span class="nt"></param></span>
	<span class="nt"></interceptor-ref></span>
	<span class="nt"></interceptor-stack></span>
	<span class="nt"></interceptors></span>

	<span class="nt"><default-interceptor-ref</span> <span class="na">name=</span><span class="s">"appDefault"</span> <span class="nt">/></span>
	</code></pre></div></div>

	<p>The value of node <code class="language-plaintext highlighter-rouge"><param name="params.excludeParams"></code> is a comma-delimited list of regular expressions or simple
	Strings that identify request parameters that should NOT be processed by the Parameters interceptor. To exclude
	the <code class="language-plaintext highlighter-rouge">submit</code> parameter (which is the name of the submit button in the form code above), I just added <code class="language-plaintext highlighter-rouge">submit</code> to the list.</p>

	<p>See the <a href="../core-developers/struts-default-xml">Basic Stack of Interceptors described here</a> to view the initial
	set of parameter names/regular expressions to exclude. Be sure to copy over the list of parameters already being excluded
	and then add your own parameters to the end separated by commas.</p>

	<h2 id="example-application">Example Application</h2>

	<p>Download the example application, <a href="https://github.com/apache/struts-examples/tree/master/exclude-parameters">exclude-params</a>
	that demonstrates excluding a request parameter. See the project’s README.txt file for how to build and run the application.</p>

	<p>To see the log messages written when not excluding the submit parameter remove the <code class="language-plaintext highlighter-rouge">,submit</code> from the list of excluded
	parameter values in the struts.xml file. Then rebuild and redeploy the application and view the console when running the application.</p>

	<h2 id="summary">Summary</h2>

	<p>It’s a nice feature of the Struts 2 framework that it logs during development which request parameters will and will not
	be processed. During development of a Struts 2 web application it’s a good practice to review these log messages to determine
	if there are any parameters that the framework should not process. For those parameters the Struts 2 framework should
	not process add the parameter name (or a regular expression that can be used to identify multiple parameter names)
	to the comma-delimited list that is the value for the <code class="language-plaintext highlighter-rouge"><param name="params.excludeParams"></code> node.</p>

	<table>
	<tbody>
	<tr>
	<td>Return to <a href="preperable-interface">Preparable Interface</a></td>
	<td>or</td>
	<td>back to <a href="index">Getting started</a></td>
	</tr>
	</tbody>
	</table>

	</section>
	</article>


	<footer class="container">
	<div class="col-md-12">
	Copyright © 2000-2022 <a href="https://www.apache.org/">The Apache Software Foundation</a>.
	Apache Struts, Struts, Apache, the Apache feather logo, and the Apache Struts project logos are
	trademarks of The Apache Software Foundation. All Rights Reserved.
	</div>
	<div class="col-md-12">Logo and website design donated by <a href="https://softwaremill.com/">SoftwareMill</a>.</div>
	</footer>

	<script>!function (d, s, id) {
	var js, fjs = d.getElementsByTagName(s)[0];
	if (!d.getElementById(id)) {
	js = d.createElement(s);
	js.id = id;
	js.src = "//platform.twitter.com/widgets.js";
	fjs.parentNode.insertBefore(js, fjs);
	}
	}(document, "script", "twitter-wjs");</script>
	<script src="https://apis.google.com/js/platform.js" async="async" defer="defer"></script>

	<div id="fb-root"></div>

	<script>(function (d, s, id) {
	var js, fjs = d.getElementsByTagName(s)[0];
	if (d.getElementById(id)) return;
	js = d.createElement(s);
	js.id = id;
	js.src = "//connect.facebook.net/en_GB/all.js#xfbml=1";
	fjs.parentNode.insertBefore(js, fjs);
	}(document, 'script', 'facebook-jssdk'));</script>


	</body>
	</html>