Google Git
Sign in
apache / struts-site / 96c1b0f4b7a3472e1f0625ac076685b6d9a43aa9 / . / content / core-developers / annotation-workflow-interceptor.html
blob: a93b19ddbe39fb31d14bec8114f8e80f223053e4 [file] [log] [blame]
<!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>Annotation Workflow Interceptor</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="/highlighter/github-theme.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>
</head>
<body>
<a href="http://github.com/apache/struts" class="github-ribbon">
<img style="position: absolute; right: 0; border: 0;" src="https://s3.amazonaws.com/github/ribbons/forkme_right_red_aa0000.png" alt="Fork me on GitHub">
</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-2021.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>
</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 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><a href="/contributors/">Contributors Guide</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="https://cwiki.apache.org/confluence/display/WW/Contributors+Guide">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/core-developers/annotation-workflow-interceptor.md" title="Edit this page on GitHub">Edit on GitHub</a>
<a href="interceptors.html" title="back to Interceptors"><< back to Interceptors</a>
<h1 id="annotation-workflow-interceptor">Annotation Workflow Interceptor</h1>
<p>Invokes any annotated methods on the action. Specifically, it supports the following annotations</p>
<ul>
<li><code class="highlighter-rouge">@Before</code> - will be invoked before the action method. If the returned value is not null, it is returned as the action
result code</li>
<li><code class="highlighter-rouge">@BeforeResult</code> - will be invoked after the action method but before the result execution</li>
<li><code class="highlighter-rouge">@After</code> - will be invoked after the action method and result execution</li>
</ul>
<p>There can be multiple methods marked with the same annotations, but the order of their execution is not guaranteed.
However, the annotated methods on the superclass chain are guaranteed to be invoked before the annotated method in the current
class in the case of a <code class="highlighter-rouge">@Before</code> annotations and after, if the annotations is <code class="highlighter-rouge">@After</code>.</p>
<h2 id="examples">Examples</h2>
<div class="language-java highlighter-rouge"><div class="highlight"><pre class="highlight"><code> <span class="kd">public</span> <span class="kd">class</span> <span class="nc">BaseAnnotatedAction</span> <span class="o">{</span>
<span class="kd">protected</span> <span class="n">String</span> <span class="n">log</span> <span class="o">=</span> <span class="s">""</span><span class="o">;</span>
<span class="nd">@Before</span>
<span class="kd">public</span> <span class="n">String</span> <span class="nf">baseBefore</span><span class="o">()</span> <span class="o">{</span>
<span class="n">log</span> <span class="o">=</span> <span class="n">log</span> <span class="o">+</span> <span class="s">"baseBefore-"</span><span class="o">;</span>
<span class="k">return</span> <span class="kc">null</span><span class="o">;</span>
<span class="o">}</span>
<span class="o">}</span>
<span class="kd">public</span> <span class="kd">class</span> <span class="nc">AnnotatedAction</span> <span class="kd">extends</span> <span class="n">BaseAnnotatedAction</span> <span class="o">{</span>
<span class="nd">@Before</span>
<span class="kd">public</span> <span class="n">String</span> <span class="nf">before</span><span class="o">()</span> <span class="o">{</span>
<span class="n">log</span> <span class="o">=</span> <span class="n">log</span> <span class="o">+</span> <span class="s">"before"</span><span class="o">;</span>
<span class="k">return</span> <span class="kc">null</span><span class="o">;</span>
<span class="o">}</span>
<span class="kd">public</span> <span class="n">String</span> <span class="nf">execute</span><span class="o">()</span> <span class="o">{</span>
<span class="n">log</span> <span class="o">=</span> <span class="n">log</span> <span class="o">+</span> <span class="s">"-execute"</span><span class="o">;</span>
<span class="k">return</span> <span class="n">Action</span><span class="o">.</span><span class="na">SUCCESS</span><span class="o">;</span>
<span class="o">}</span>
<span class="nd">@BeforeResult</span>
<span class="kd">public</span> <span class="kt">void</span> <span class="nf">beforeResult</span><span class="o">()</span> <span class="kd">throws</span> <span class="n">Exception</span> <span class="o">{</span>
<span class="n">log</span> <span class="o">=</span> <span class="n">log</span> <span class="o">+</span><span class="s">"-beforeResult"</span><span class="o">;</span>
<span class="o">}</span>
<span class="nd">@After</span>
<span class="kd">public</span> <span class="kt">void</span> <span class="nf">after</span><span class="o">()</span> <span class="o">{</span>
<span class="n">log</span> <span class="o">=</span> <span class="n">log</span> <span class="o">+</span> <span class="s">"-after"</span><span class="o">;</span>
<span class="o">}</span>
<span class="o">}</span>
</code></pre></div></div>
<p>Configure a stack in struts.xml that replaces the PrepareInterceptor with the AnnotationWorkflowInterceptor:</p>
<div class="language-xml highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="nt">&lt;interceptor-stack</span> <span class="na">name=</span><span class="s">"annotatedStack"</span><span class="nt">&gt;</span>
<span class="nt">&lt;interceptor-ref</span> <span class="na">name=</span><span class="s">"static-params"</span><span class="nt">/&gt;</span>
<span class="nt">&lt;interceptor-ref</span> <span class="na">name=</span><span class="s">"params"</span><span class="nt">/&gt;</span>
<span class="nt">&lt;interceptor-ref</span> <span class="na">name=</span><span class="s">"conversionError"</span><span class="nt">/&gt;</span>
<span class="nt">&lt;interceptor-ref</span> <span class="na">name=</span><span class="s">"annotationWorkflow"</span><span class="nt">/&gt;</span>
<span class="nt">&lt;/interceptor-stack&gt;</span>
</code></pre></div></div>
<p>Given an Action, AnnotatedAction, add a reference to the AnnotationWorkflowInterceptor interceptor.</p>
<div class="language-xml highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="nt">&lt;action</span> <span class="na">name=</span><span class="s">"AnnotatedAction"</span> <span class="na">class=</span><span class="s">"com.examples.AnnotatedAction"</span><span class="nt">&gt;</span>
<span class="nt">&lt;interceptor-ref</span> <span class="na">name=</span><span class="s">"annotationWorkflow"</span><span class="nt">/&gt;</span>
<span class="nt">&lt;result</span> <span class="na">name=</span><span class="s">"success"</span> <span class="na">type=</span><span class="s">"freemarker"</span><span class="nt">&gt;</span>good_result.ftl<span class="nt">&lt;/result&gt;</span>
<span class="nt">&lt;/action&gt;</span>
</code></pre></div></div>
<p>With the interceptor applied and the action executed on <code class="highlighter-rouge">AnnotatedAction</code> the log instance variable will contain
<code class="highlighter-rouge">baseBefore-before-execute-beforeResult-after</code>.</p>
</section>
</article>
<footer class="container">
<div class="col-md-12">
Copyright &copy; 2000-2018 <a href="http://www.apache.org/">The Apache Software Foundation </a>.
All Rights Reserved.
</div>
<div class="col-md-12">
Apache Struts, Struts, Apache, the Apache feather logo, and the Apache Struts project logos are
trademarks of The Apache Software Foundation.
</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>