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Posted to commits@tapestry.apache.org by bo...@apache.org on 2017/09/16 01:54:20 UTC
svn commit: r1018226 [36/41] - in /websites/production/tapestry/content: ./
cache/ styles/
Modified: websites/production/tapestry/content/tapestry-for-jsf-users.html
==============================================================================
--- websites/production/tapestry/content/tapestry-for-jsf-users.html (original)
+++ websites/production/tapestry/content/tapestry-for-jsf-users.html Sat Sep 16 01:54:19 2017
@@ -27,6 +27,15 @@
</title>
<link type="text/css" rel="stylesheet" href="/resources/space.css" />
+ <link href='/resources/highlighter/styles/shCoreCXF.css' rel='stylesheet' type='text/css' />
+ <link href='/resources/highlighter/styles/shThemeCXF.css' rel='stylesheet' type='text/css' />
+ <script src='/resources/highlighter/scripts/shCore.js' type='text/javascript'></script>
+ <script src='/resources/highlighter/scripts/shBrushJava.js' type='text/javascript'></script>
+ <script src='/resources/highlighter/scripts/shBrushXml.js' type='text/javascript'></script>
+ <script>
+ SyntaxHighlighter.defaults['toolbar'] = false;
+ SyntaxHighlighter.all();
+ </script>
<link href="/styles/style.css" rel="stylesheet" type="text/css"/>
@@ -36,26 +45,13 @@
<div class="wrapper bs">
- <div id="navigation"><div class="nav"><ul class="alternate"><li><a href="index.html">Home</a></li><li><a href="getting-started.html">Getting Started</a></li><li><a href="documentation.html">Documentation</a></li><li><a href="download.html">Download</a></li><li><a href="about.html">About</a></li><li><a class="external-link" href="http://www.apache.org/licenses/LICENSE-2.0">License</a></li><li><a href="community.html">Community</a></li><li><a class="external-link" href="http://www.apache.org/security/">Security</a></li><li><a class="external-link" href="http://www.apache.org/">Apache</a></li><li><a class="external-link" href="http://www.apache.org/foundation/sponsorship.html">Sponsorship</a></li><li><a class="external-link" href="http://www.apache.org/foundation/thanks.html">Thanks</a></li></ul></div>
-
-</div>
+ <div id="navigation"><div class="nav"><ul class="alternate"><li><a href="index.html">Home</a></li><li><a href="getting-started.html">Getting Started</a></li><li><a href="documentation.html">Documentation</a></li><li><a href="download.html">Download</a></li><li><a href="about.html">About</a></li><li><a class="external-link" href="http://www.apache.org/licenses/LICENSE-2.0">License</a></li><li><a href="community.html">Community</a></li><li><a class="external-link" href="http://www.apache.org/security/">Security</a></li><li><a class="external-link" href="http://www.apache.org/">Apache</a></li><li><a class="external-link" href="http://www.apache.org/foundation/sponsorship.html">Sponsorship</a></li><li><a class="external-link" href="http://www.apache.org/foundation/thanks.html">Thanks</a></li></ul></div></div>
<div id="top">
- <div id="smallbanner"><div class="searchbox" style="float:right;margin: .3em 1em .1em 1em"><span style="color: #999; font-size: 90%">Tapestry docs, issues, wikis & blogs:</span>
-<form enctype="application/x-www-form-urlencoded" method="get" action="http://tapestry.apache.org/search.html">
- <input type="text" name="q">
- <input type="submit" value="Search">
-</form>
-
-</div>
-
-
-<div class="emblem" style="float:left"><p><a href="index.html"><span class="confluence-embedded-file-wrapper"><img class="confluence-embedded-image confluence-external-resource" src="http://tapestry.apache.org/images/tapestry_small.png" data-image-src="http://tapestry.apache.org/images/tapestry_small.png"></span></a></p></div>
-
-
-<div class="title" style="float:left; margin: 0 0 0 3em"><h1 id="SmallBanner-PageTitle">Tapestry for JSF Users</h1></div>
-
-</div>
+ <div id="smallbanner"><div class="searchbox" style="float:right;margin: .3em 1em .1em 1em"><span style="color: #999; font-size: 90%">Tapestry docs, issues, wikis & blogs:</span><form enctype="application/x-www-form-urlencoded" method="get" action="http://tapestry.apache.org/search.html">
+ <input type="text" name="q">
+ <input type="submit" value="Search">
+</form></div><div class="emblem" style="float:left"><p><a href="index.html"><span class="confluence-embedded-file-wrapper"><img class="confluence-embedded-image confluence-external-resource" src="http://tapestry.apache.org/images/tapestry_small.png" data-image-src="http://tapestry.apache.org/images/tapestry_small.png"></span></a></p></div><div class="title" style="float:left; margin: 0 0 0 3em"><h1 id="SmallBanner-PageTitle">Tapestry for JSF Users</h1></div></div>
<div class="clearer"></div>
</div>
@@ -67,34 +63,74 @@
</div>
<div id="content">
- <div id="ConfluenceContent"><p><parameter ac:name="hidden">true</parameter><parameter ac:name="atlassian-macro-output-type">INLINE</parameter><rich-text-body><p>a brief guide for learning Tapestry, designed for those who already know JavaServer Faces (JSF)</p></rich-text-body></p><p> </p><p>This is a brief guide for learning Tapestry, designed for those who already know JavaServer Faces (JSF).</p><p>Because both JSF and Tapestry are component oriented frameworks designed to serve mostly the same kinds of problems in similar ways, developers who already know JSF will find it very easy to learn Tapestry. In fact, Facelets, the default view technology in JSF 2.0, was created specifically to give JSF a Tapestry-like templating capability, so Facelets users should feel right at home.</p><parameter ac:name="style">float:right</parameter><parameter ac:name="title">Related Articles</parameter><parameter ac:name="class">aui-label</parameter><rich-text-body><paramete
r ac:name="showLabels">false</parameter><parameter ac:name="showSpace">false</parameter><parameter ac:name="title">Related Articles</parameter><parameter ac:name="cql">label = "new-users" and space = currentSpace()</parameter></rich-text-body><p>Since almost all modern JSF applications use Facelets as their view technology, we assume the use of Facelets here when discussing JSF features.</p><p>JSF is a rich, mature web framework specification, and there are lots of smart people who use it productively. This guide isn't intended as a pro-versus-con comparison or as advocacy of any kind. Instead, it just attempts to make transitions between the two frameworks easier, regardless of the reason for doing so.</p><h2 id="TapestryforJSFUsers-Side-by-sideComparison">Side-by-side Comparison</h2><p>JSF and Tapestry have a lot of superficial similarities, so the first steps in that transition are all about relating similar concepts, terms and components in your mind:</p><div class="table-wrap">
<table class="confluenceTable"><tbody><tr><th colspan="1" rowspan="1" class="confluenceTh"><p>Concepts & Terminology</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>JSF</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>Tapestry</p></th></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Java class associated with a page or component</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>"Backing Bean"</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>"<a href="component-classes.html">Component Class</a>"</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Component attributes/parameters</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>"attributes"</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>"<a href="component-parameters.html">parameters</a>"</p></td></tr><tr><th colspan="1" rowspan="1" class="confluenceTh"><p>Common Attributes/Parameters</p></th><th colspan="1" rowspan="1" class="conflue
nceTh"><p>JSF</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>Tapestry</p></th></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>HTML Attribute used for invisible instrumentation</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>jsfc="someComponentType"</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a href="component-templates.html">t:type="someComponentType"</a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>CSS "class" attribute name</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>styleClass</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>class</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Alternating "zebra" striped rows</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>rowclasses="class1,class2"</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>class="${cycle:class1,class2}" using <a class="external-link" href="https://wiki.apache.org/tapestry
/Tapestry5HowToAddBindingPrefixCycle">cycle binding prefix</a>, or with CSS: .rowClass:nth-child(even) {background-color: #e8e8e8;}</p></td></tr><tr><th colspan="1" rowspan="1" class="confluenceTh"><p>Output and Messages</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>JSF</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>Tapestry</p></th></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Escaped HTML from property</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:outputText value="myBean.myValue"/></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>${myValue}</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Raw HTML from property</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>#{myBean.myValue}</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/OutputRaw.html"><t:outp
utRaw value="myValue"/></a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Error messages</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:message> and <h:messages></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/Error.html"><t:error></a> and <a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/Errors.html"><t:errors></a> (for forms) or <a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/Alerts.html"><t:alerts></a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Image display</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:graphicImage></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><em>use standard <img> ta
g</em></p></td></tr><tr><th colspan="1" rowspan="1" class="confluenceTh"><p>Conditionals and Looping</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>JSF</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>Tapestry</p></th></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Render-time loop</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><ui:repeat></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/Loop.html"><t:loop></a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Compile-time loop</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><c:forEach></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/Loop.html"><t:loop></a></p></td></tr><tr><td col
span="1" rowspan="1" class="confluenceTd"><p>Conditional</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><c:if test="#{myBean.myValue}"></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/If.html"><t:if test="myValue"></a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Conditional</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><ui:fragment rendered="#{myBean.someCondition}"/>...</ui:fragment></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/If.html"><t:if test="someCondition">...</t:if></a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Switch</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><c:choose><c:when ... &
gt;</c:choose></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>See <a href="switching-cases.html">Switching Cases</a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Server-side comment</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><ui:remove></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a href="component-templates.html"><t:remove></a></p></td></tr><tr><th colspan="1" rowspan="1" class="confluenceTh"><p>Links and Buttons</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>JSF</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>Tapestry</p></th></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Navigational link</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:link outcome="nextpage.xhtml"/></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/comp
onents/PageLink.html"><t:pagelink page="nextpage"/></a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Event-triggering link, without form submission</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><em>not available</em></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/ActionLink.html"><t:actionLink></a> or <a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/EventLink.html"><t:eventLink></a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Form submission link</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:commandLink></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/LinkSubmit.htm
l"><t:linkSubmit></a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Form submission button</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:commandButton></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/Submit.html"><t:submit></a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Link to Javascript file</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:outputScript></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><em><script> or use @Import in component class</em></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Link to CSS file</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:outputStylesheet></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><em><style> or use @Import in component class</em><
/p></td></tr><tr><th colspan="1" rowspan="1" class="confluenceTh"><p>Grids, Tables and Trees</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>JSF</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>Tapestry</p></th></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Tabular data in <table></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:datatable></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/Grid.html"><t:grid></a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Table used for layout</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:panelGrid> with <h:panelGroup></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><em>use standard <table> tag</em></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Hierarchical tree</p>
</td><td colspan="1" rowspan="1" class="confluenceTd"><p><em>depends on component library</em></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/Tree.html"><t:tree></a></p></td></tr><tr><th colspan="1" rowspan="1" class="confluenceTh"><p>Form Tags/Components</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>JSF</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>Tapestry</p></th></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Form</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:form></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/Form.html"><t:form></a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Single-line text input field</p></td><td colspan="1
" rowspan="1" class="confluenceTd"><p><h:inputText></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/TextField.html"><t:textField></a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Password field</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:inputSecret></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/PasswordField.html"><t:passwordfield></a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Select menu</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:selectOneMenu></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/compon
ents/Select.html"><t:select></a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Checkbox</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:selectBooleanCheckbox></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/Checkbox.html"><t:checkbox></a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Checkbox list</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:selectManyCheckbox></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/Checklist.html"><t:checklist></a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Radio button list</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:selectOneRadio></p></td><td cols
pan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/RadioGroup.html"><t:radioGroup></a> with <a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/Radio.html"><t:radio></a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Multiple select menu</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:selectManyListbox></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><em>not available</em> (but see Palette and Checklist)</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Hidden field</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:inputHidden></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/Hidden.html"
><t:hidden></a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>textarea tag</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:inputTextarea></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/TextArea.html"><t:textArea></a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Label tag</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:outputLabel for="..."></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/Label.html"><t:label for="..."></a></p></td></tr></tbody></table></div><p>Some important notes:</p><ul><li>With Tapestry, you don't use the ${...} syntax with parameters of components. Just use a bare expression within the quotes. For example:
<t:textfield value="myProperty"> instead of <t:textfield value="${myProperty}">, because in the latter case the expression is converted to a read-only string before the textfield component gets it.</li></ul><h2 id="TapestryforJSFUsers-HelloWorldComparison">Hello World Comparison</h2><p>Faces templates and Tapestry templates are superficially quite similar.</p><rich-text-body><rich-text-body><parameter ac:name="language">xml</parameter><parameter ac:name="title">JSF template (helloworld.xhtml)</parameter><plain-text-body><html xmlns="http://www.w3.org/1999/xhtml"
+ <div id="ConfluenceContent"><p> </p><p>This is a brief guide for learning Tapestry, designed for those who already know JavaServer Faces (JSF).</p><p>Because both JSF and Tapestry are component oriented frameworks designed to serve mostly the same kinds of problems in similar ways, developers who already know JSF will find it very easy to learn Tapestry. In fact, Facelets, the default view technology in JSF 2.0, was created specifically to give JSF a Tapestry-like templating capability, so Facelets users should feel right at home.</p><div class="aui-label" style="float:right" title="Related Articles"><h3>Related Articles</h3><ul class="content-by-label"><li>
+ <div>
+ <span class="icon aui-icon aui-icon-small aui-iconfont-page-default" title="Page">Page:</span>
+ </div>
+ <div class="details">
+ <a href="tapestry-for-jsf-users.html">Tapestry for JSF Users</a>
+ </div> </li><li>
+ <div>
+ <span class="icon aui-icon aui-icon-small aui-iconfont-page-default" title="Page">Page:</span>
+ </div>
+ <div class="details">
+ <a href="tapestry-tutorial.html">Tapestry Tutorial</a>
+ </div> </li><li>
+ <div>
+ <span class="icon aui-icon aui-icon-small aui-iconfont-page-default" title="Page">Page:</span>
+ </div>
+ <div class="details">
+ <a href="principles.html">Principles</a>
+ </div> </li><li>
+ <div>
+ <span class="icon aui-icon aui-icon-small aui-iconfont-page-default" title="Page">Page:</span>
+ </div>
+ <div class="details">
+ <a href="getting-started.html">Getting Started</a>
+ </div> </li><li>
+ <div>
+ <span class="icon aui-icon aui-icon-small aui-iconfont-page-default" title="Page">Page:</span>
+ </div>
+ <div class="details">
+ <a href="introduction.html">Introduction</a>
+ </div> </li></ul></div><p>Since almost all modern JSF applications use Facelets as their view technology, we assume the use of Facelets here when discussing JSF features.</p><p>JSF is a rich, mature web framework specification, and there are lots of smart people who use it productively. This guide isn't intended as a pro-versus-con comparison or as advocacy of any kind. Instead, it just attempts to make transitions between the two frameworks easier, regardless of the reason for doing so.</p><h2 id="TapestryforJSFUsers-Side-by-sideComparison">Side-by-side Comparison</h2><p>JSF and Tapestry have a lot of superficial similarities, so the first steps in that transition are all about relating similar concepts, terms and components in your mind:</p><div class="table-wrap"><table class="confluenceTable"><tbody><tr><th colspan="1" rowspan="1" class="confluenceTh"><p>Concepts & Terminology</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>JSF</p></th><th colspan="1" rowspan="
1" class="confluenceTh"><p>Tapestry</p></th></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Java class associated with a page or component</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>"Backing Bean"</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>"<a href="component-classes.html">Component Class</a>"</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Component attributes/parameters</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>"attributes"</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>"<a href="component-parameters.html">parameters</a>"</p></td></tr><tr><th colspan="1" rowspan="1" class="confluenceTh"><p>Common Attributes/Parameters</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>JSF</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>Tapestry</p></th></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>HTML Attribute used for invisible instrumentation</p></td><td cols
pan="1" rowspan="1" class="confluenceTd"><p>jsfc="someComponentType"</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a href="component-templates.html">t:type="someComponentType"</a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>CSS "class" attribute name</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>styleClass</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>class</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Alternating "zebra" striped rows</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>rowclasses="class1,class2"</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>class="${cycle:class1,class2}" using <a class="external-link" href="https://wiki.apache.org/tapestry/Tapestry5HowToAddBindingPrefixCycle">cycle binding prefix</a>, or with CSS: .rowClass:nth-child(even) {background-color: #e8e8e8;}</p></td></tr><tr><th colspan="1" rowspan="1" class="confluenceTh"><p>Output and Messag
es</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>JSF</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>Tapestry</p></th></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Escaped HTML from property</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:outputText value="myBean.myValue"/></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>${myValue}</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Raw HTML from property</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>#{myBean.myValue}</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/OutputRaw.html"><t:outputRaw value="myValue"/></a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Error messages</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:message> and <h:messages></p
></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/Error.html"><t:error></a> and <a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/Errors.html"><t:errors></a> (for forms) or <a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/Alerts.html"><t:alerts></a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Image display</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:graphicImage></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><em>use standard <img> tag</em></p></td></tr><tr><th colspan="1" rowspan="1" class="confluenceTh"><p>Conditionals and Looping</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>JSF</p></th><th colspan="1" rowspan="1" class="confluence
Th"><p>Tapestry</p></th></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Render-time loop</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><ui:repeat></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/Loop.html"><t:loop></a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Compile-time loop</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><c:forEach></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/Loop.html"><t:loop></a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Conditional</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><c:if test="#{myBean.myValue}"></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a
class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/If.html"><t:if test="myValue"></a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Conditional</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><ui:fragment rendered="#{myBean.someCondition}"/>...</ui:fragment></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/If.html"><t:if test="someCondition">...</t:if></a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Switch</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><c:choose><c:when ... ></c:choose></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>See <a href="switching-cases.html">Switching Cases</a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Server-side
comment</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><ui:remove></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a href="component-templates.html"><t:remove></a></p></td></tr><tr><th colspan="1" rowspan="1" class="confluenceTh"><p>Links and Buttons</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>JSF</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>Tapestry</p></th></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Navigational link</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:link outcome="nextpage.xhtml"/></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/PageLink.html"><t:pagelink page="nextpage"/></a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Event-triggering link, without form submission</p></td><td colspan="1" rowspan="1" clas
s="confluenceTd"><p><em>not available</em></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/ActionLink.html"><t:actionLink></a> or <a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/EventLink.html"><t:eventLink></a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Form submission link</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:commandLink></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/LinkSubmit.html"><t:linkSubmit></a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Form submission button</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:commandButton></p></td><td co
lspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/Submit.html"><t:submit></a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Link to Javascript file</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:outputScript></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><em><script> or use @Import in component class</em></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Link to CSS file</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:outputStylesheet></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><em><style> or use @Import in component class</em></p></td></tr><tr><th colspan="1" rowspan="1" class="confluenceTh"><p>Grids, Tables and Trees</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>JSF</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>T
apestry</p></th></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Tabular data in <table></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:datatable></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/Grid.html"><t:grid></a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Table used for layout</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:panelGrid> with <h:panelGroup></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><em>use standard <table> tag</em></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Hierarchical tree</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><em>depends on component library</em></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/curr
ent/apidocs/org/apache/tapestry5/corelib/components/Tree.html"><t:tree></a></p></td></tr><tr><th colspan="1" rowspan="1" class="confluenceTh"><p>Form Tags/Components</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>JSF</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>Tapestry</p></th></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Form</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:form></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/Form.html"><t:form></a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Single-line text input field</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:inputText></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/core
lib/components/TextField.html"><t:textField></a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Password field</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:inputSecret></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/PasswordField.html"><t:passwordfield></a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Select menu</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:selectOneMenu></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/Select.html"><t:select></a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Checkbox</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:selectBooleanCheckbox></p></td><
td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/Checkbox.html"><t:checkbox></a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Checkbox list</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:selectManyCheckbox></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/Checklist.html"><t:checklist></a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Radio button list</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:selectOneRadio></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/RadioGroup.html"><t:radioGroup></a> with <a class="e
xternal-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/Radio.html"><t:radio></a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Multiple select menu</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:selectManyListbox></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><em>not available</em> (but see Palette and Checklist)</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Hidden field</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:inputHidden></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/Hidden.html"><t:hidden></a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>textarea tag</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:inputTextarea></p></td><td colspan="1" rowspa
n="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/TextArea.html"><t:textArea></a></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Label tag</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><h:outputLabel for="..."></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/Label.html"><t:label for="..."></a></p></td></tr></tbody></table></div><p>Some important notes:</p><ul><li>With Tapestry, you don't use the ${...} syntax with parameters of components. Just use a bare expression within the quotes. For example: <t:textfield value="myProperty"> instead of <t:textfield value="${myProperty}">, because in the latter case the expression is converted to a read-only string before the textfield component gets it.</li></ul
><h2 id="TapestryforJSFUsers-HelloWorldComparison">Hello World Comparison</h2><p>Faces templates and Tapestry templates are superficially quite similar.</p><div class="sectionColumnWrapper"><div class="sectionMacro"><div class="sectionMacroRow"><div class="columnMacro"><div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1px;"><b>JSF template (helloworld.xhtml)</b></div><div class="codeContent panelContent pdl">
+<pre class="brush: xml; gutter: false; theme: Default" style="font-size:12px;"><html xmlns="http://www.w3.org/1999/xhtml"
xmlns:h="http://java.sun.com/jsf/html">
<h:body>
<p><h:outputText value="#{helloWorldBean.greeting} /></p>
</h:body>
</html>
-</plain-text-body></rich-text-body><rich-text-body><parameter ac:name="language">xml</parameter><parameter ac:name="title">Tapestry template (HelloWorld.tml)</parameter><plain-text-body><html xmlns:t="http://tapestry.apache.org/schema/tapestry_5_4.xsd">
+</pre>
+</div></div></div><div class="columnMacro"><div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1px;"><b>Tapestry template (HelloWorld.tml)</b></div><div class="codeContent panelContent pdl">
+<pre class="brush: xml; gutter: false; theme: Default" style="font-size:12px;"><html xmlns:t="http://tapestry.apache.org/schema/tapestry_5_4.xsd">
<body>
<p>${greeting}</p>
</body>
</html>
-</plain-text-body></rich-text-body></rich-text-body><p>Though these are very similar, notice some differences:</p><ul><li>The #{...} syntax in JSF does not encode the underlying string, so you have to use the <h:outputText> tag if your data may contain HTML reserved characters such as <, >, or &. In contrast, the ${...} syntax in Tapestry <strong>does</strong> encode the underlying string.</li><li>In JSF, backing beans are not necessarily related one-to-one with page templates. Often several templates use the same backing bean, and one template may reference multiple backing beans. In Tapestry, they are always related one-to-one, and therefore you don't have to specify which component class your ${...} expressions are referencing.</li></ul><rich-text-body><rich-text-body><parameter ac:name="language">java</parameter><parameter ac:name="title">JSF Backing Bean (HelloWorldBean.java)</parameter><plain-text-body>@ManagedBean
+</pre>
+</div></div></div></div></div></div><p>Though these are very similar, notice some differences:</p><ul><li>The #{...} syntax in JSF does not encode the underlying string, so you have to use the <h:outputText> tag if your data may contain HTML reserved characters such as <, >, or &. In contrast, the ${...} syntax in Tapestry <strong>does</strong> encode the underlying string.</li><li>In JSF, backing beans are not necessarily related one-to-one with page templates. Often several templates use the same backing bean, and one template may reference multiple backing beans. In Tapestry, they are always related one-to-one, and therefore you don't have to specify which component class your ${...} expressions are referencing.</li></ul><div class="sectionColumnWrapper"><div class="sectionMacro"><div class="sectionMacroRow"><div class="columnMacro"><div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1px;"><b>J
SF Backing Bean (HelloWorldBean.java)</b></div><div class="codeContent panelContent pdl">
+<pre class="brush: java; gutter: false; theme: Default" style="font-size:12px;">@ManagedBean
@RequestScoped
public class HelloWorldBean {
public String getGreeting() {
return "Hello, World!";
}
}
-</plain-text-body></rich-text-body><rich-text-body><parameter ac:name="language">java</parameter><parameter ac:name="title">Tapestry page class (HelloWorld.java)</parameter><plain-text-body>public class HelloWorld {
+</pre>
+</div></div></div><div class="columnMacro"><div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1px;"><b>Tapestry page class (HelloWorld.java)</b></div><div class="codeContent panelContent pdl">
+<pre class="brush: java; gutter: false; theme: Default" style="font-size:12px;">public class HelloWorld {
public String getGreeting() {
return "Hello, World!";
}
}
-</plain-text-body></rich-text-body></rich-text-body><h2 id="TapestryforJSFUsers-Expressionsintemplates">Expressions in templates</h2><p>JSF uses the Unified Expression Language with the #{...} or ${...} syntax for accessing Backing Bean properties. For its part, Tapestry uses the ${...} syntax with a similar but intentially limited expression language called <a href="property-expressions.html">Property Expressions</a>. Both allow easy access to properties via the usual JavaBean conventions, but with Tapestry you don't have to specify which class the expression starts at (because it always starts at the component class corresponding to the template). Some comparisons:</p><div class="table-wrap"><table class="confluenceTable"><tbody><tr><td colspan="1" rowspan="1" class="confluenceTd"><p> </p></td><th colspan="1" rowspan="1" class="confluenceTh"><p>JSF Syntax</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>Tapestry Syntax</p></th></tr><tr><td colspan="1" rowspan="1"
class="confluenceTd"><p>Property (calls getEmployeeName() or setEmployeeName())</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>#{employeeBean.employeeName}</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>${employeeName}</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Boolean property (calls isHourly() or setHourly())</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>#{employeeBean.hourly}</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>${hourly}</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Property chain</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>#{employeeBean.address.street}</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>${address.street}</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Null-safe property chain</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>#{employeeBean.address.street}</p></td><td colspan="1" rowspan="1" class
="confluenceTd"><p>${address?.street}</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>5th element in a List</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>#{employeeBean.employees[5].name}</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>${employees.get(5).name}</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Negation</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>#{! employeeBean.hourly}</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>${! hourly}</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Arithmetic & relational operators</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>+-*/% div mod</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><em>not available</em></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Relational operators</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>== != ne < lt > gt <= le >=
ge</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><em>not available</em></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Ternary operator</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>#{myBean.foo < 0 ? 'bar' : 'baz'}</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><em>not available</em></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Method calling</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>#{myBean.employees.size()}</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>${employees.size()}</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Iterated Range</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><em>not avaialble</em></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>${1..10}</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Iterated Range (calculated)</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><
em>not avaialble</em></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>${1..groupList.size()}</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>List</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><em>not available</em></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>${ [ user.name, user.email, user.phone ] }</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Map</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><em>not available</em></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>${ { 'id':'4039','type':'hourly' } }</p></td></tr></tbody></table></div><p>Features shown as <em>not available</em> above are absent by design, because (in both Tapestry and JSF) it is considered best to keep complex logic in the component class rather than in the template.</p><h2 id="TapestryforJSFUsers-EventHandling&PageNavigation">Event Handling & Page Navigation</h2><h3 id="TapestryforJSFUsers-Eventha
ndling">Event handling</h3><p>In JSF, you specify the event via the <code>action</code> parameter (for example, <h:commandButton value="Submit" action="employeeBean.saveChanges">). For Tapestry, event handler methods are found by method naming conventions (onSomeEvent() or by method annotations (@Event), based on a combination of the "t:id" attribute and event name, and the action name used depends on the component. For example, the "<t:actionlink>" component in Tapestry emits an "action" event when clicked, and you handle that event in your "onAction()" method.</p><h2 id="TapestryforJSFUsers-Validation">Validation</h2><p>Tapestry applications can use JSR 303 Bean Validation annotations that JSF users should be familiar with:</p><parameter ac:name="language">java</parameter><plain-text-body>public class Employee {
+</pre>
+</div></div></div></div></div></div><h2 id="TapestryforJSFUsers-Expressionsintemplates">Expressions in templates</h2><p>JSF uses the Unified Expression Language with the #{...} or ${...} syntax for accessing Backing Bean properties. For its part, Tapestry uses the ${...} syntax with a similar but intentially limited expression language called <a href="property-expressions.html">Property Expressions</a>. Both allow easy access to properties via the usual JavaBean conventions, but with Tapestry you don't have to specify which class the expression starts at (because it always starts at the component class corresponding to the template). Some comparisons:</p><div class="table-wrap"><table class="confluenceTable"><tbody><tr><td colspan="1" rowspan="1" class="confluenceTd"><p> </p></td><th colspan="1" rowspan="1" class="confluenceTh"><p>JSF Syntax</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>Tapestry Syntax</p></th></tr><tr><td colspan="1" rowspan="1" class="confluenc
eTd"><p>Property (calls getEmployeeName() or setEmployeeName())</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>#{employeeBean.employeeName}</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>${employeeName}</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Boolean property (calls isHourly() or setHourly())</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>#{employeeBean.hourly}</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>${hourly}</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Property chain</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>#{employeeBean.address.street}</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>${address.street}</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Null-safe property chain</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>#{employeeBean.address.street}</p></td><td colspan="1" rowspan="1" class="confluenceTd">
<p>${address?.street}</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>5th element in a List</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>#{employeeBean.employees[5].name}</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>${employees.get(5).name}</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Negation</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>#{! employeeBean.hourly}</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>${! hourly}</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Arithmetic & relational operators</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>+-*/% div mod</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><em>not available</em></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Relational operators</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>== != ne < lt > gt <= le >= ge</p></td><td c
olspan="1" rowspan="1" class="confluenceTd"><p><em>not available</em></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Ternary operator</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>#{myBean.foo < 0 ? 'bar' : 'baz'}</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><em>not available</em></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Method calling</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>#{myBean.employees.size()}</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>${employees.size()}</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Iterated Range</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><em>not avaialble</em></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>${1..10}</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Iterated Range (calculated)</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><em>not avaialble
</em></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>${1..groupList.size()}</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>List</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><em>not available</em></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>${ [ user.name, user.email, user.phone ] }</p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>Map</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><em>not available</em></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>${ { 'id':'4039','type':'hourly' } }</p></td></tr></tbody></table></div><p>Features shown as <em>not available</em> above are absent by design, because (in both Tapestry and JSF) it is considered best to keep complex logic in the component class rather than in the template.</p><h2 id="TapestryforJSFUsers-EventHandling&PageNavigation">Event Handling & Page Navigation</h2><h3 id="TapestryforJSFUsers-Eventhandling">Event ha
ndling</h3><p>In JSF, you specify the event via the <code>action</code> parameter (for example, <h:commandButton value="Submit" action="employeeBean.saveChanges">). For Tapestry, event handler methods are found by method naming conventions (onSomeEvent() or by method annotations (@Event), based on a combination of the "t:id" attribute and event name, and the action name used depends on the component. For example, the "<t:actionlink>" component in Tapestry emits an "action" event when clicked, and you handle that event in your "onAction()" method.</p><h2 id="TapestryforJSFUsers-Validation">Validation</h2><p>Tapestry applications can use JSR 303 Bean Validation annotations that JSF users should be familiar with:</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
+<pre class="brush: java; gutter: false; theme: Default" style="font-size:12px;">public class Employee {
@Validate("required,minlength=2,maxlength=100")
private String lastName;
@NotNull @Email private String email;
-</plain-text-body><h3 id="TapestryforJSFUsers-Post-Redirect-GetNavigation">Post-Redirect-Get Navigation</h3><p>By default, most JSF URLs are "one page behind". That is, when you click on an <h:commandLink> link or submit a form, the request goes back to the originating page, and the server returns the contents of the <strong>next</strong> page – but the URL in the browser shows the previous page's URL. To fix this in JSF you add the "?faces-redirect=true" to the URL you return from event handlers, which causes JSF to send a redirect to the browser to navigate to the next page.</p><p>By contrast, Tapestry implements this Post-Redirect-Get pattern by default. The URL will always reflect the page you're seeing, not the page you just came from.</p><p>Note that by default Tapestry does not save property values across the Post-Redirect-Get cycle. This means that you have to consider how (and whether) to persist property values from one page to the next. The usual solution is t
o either make the values part of the page's <a href="navigation.html">Activation Context</a> (which means the values will be appended to the URL) or <a href="persistent-page-data.html">@Persist the properties</a> the values in the session.</p><h2 id="TapestryforJSFUsers-CustomandCompositeComponents">Custom and Composite Components</h2><p>With JSF, creating custom components is an <a class="external-link" href="http://jsfcorner.blogspot.com/2011/01/custom-components.html" rel="nofollow">advanced topic</a>. In fact, many JSF developers have <em>never</em> created a custom component. In JSF 1.x, creating each custom component requires a lot of work: creating 3 Java classes (component, component renderer and component tag), registering the component in an XML file, and registering the tag in the .tld file. In JSF 2.x <em>composite components</em> can be created without too much work (if your needs can be met by combining existing components <em>and</em> you don't need any custom Java
), but you still have to use cumbersome <composite:interface> and <composite:implementation> tags in your component templates, and you have to list the composite components in the xml namespace declaration at the top of the pages where you are using them.</p><p>Creating true custom components in JSF 2.0 still requires several steps: create a component class (generally having the @FacesComponent annotation and extending UIComponentBase), create a renderer class (generally extending Renderer), add a <renderer> section to the facesconfig file, and create a *-taglib.xml file in the WEB_INF folder that defines the namespace, tag and component type of the custom component.</p><p>In contrast, with Tapestry, <a href="component-classes.html">creating custom components</a> is a <em>beginner</em> topic: it is expected to be a daily activity for developers, because it is so easy. In fact, the steps are the same as creating a page. All you have to do is create a (potentially e
mpty) Java class in a "components" sub-package, and create a template file containing (X)HTML markup in the corresponding "components" sub-folder within your package hierarchy under /src/main/resources. You <em>use</em> a custom component just like you use any built-in Tapestry component: <code><t:mycomponent></code>.</p><p>Because they're so easy to create, Tapestry applications tend to have a lot of custom components and much less repetition of HTML than most JSF applications.</p><h2 id="TapestryforJSFUsers-OtherReferences">Other References</h2><ul><li><a class="external-link" href="http://blog.tapestry5.de/wp-content/uploads/2010/06/JSF-2.0-vs-Tapestry-5.pdf" rel="nofollow">JavaServer Faces 2.0 vs. Tapestry 5: A Head-to-Head Comparison</a> slides by Igor Drobiazko, June 2010.</li><li><a class="external-link" href="http://docs.oracle.com/javaee/6/tutorial/doc/gkhxa.html" rel="nofollow">Composite Components: Advanced Topics and Example</a> part of <em>The Java EE 6 Tutorial
</em> from Oracle</li></ul><p> </p><p></p></div>
+</pre>
+</div></div><h3 id="TapestryforJSFUsers-Post-Redirect-GetNavigation">Post-Redirect-Get Navigation</h3><p>By default, most JSF URLs are "one page behind". That is, when you click on an <h:commandLink> link or submit a form, the request goes back to the originating page, and the server returns the contents of the <strong>next</strong> page – but the URL in the browser shows the previous page's URL. To fix this in JSF you add the "?faces-redirect=true" to the URL you return from event handlers, which causes JSF to send a redirect to the browser to navigate to the next page.</p><p>By contrast, Tapestry implements this Post-Redirect-Get pattern by default. The URL will always reflect the page you're seeing, not the page you just came from.</p><p>Note that by default Tapestry does not save property values across the Post-Redirect-Get cycle. This means that you have to consider how (and whether) to persist property values from one page to the next. The usual solution is to eith
er make the values part of the page's <a href="navigation.html">Activation Context</a> (which means the values will be appended to the URL) or <a href="persistent-page-data.html">@Persist the properties</a> the values in the session.</p><h2 id="TapestryforJSFUsers-CustomandCompositeComponents">Custom and Composite Components</h2><p>With JSF, creating custom components is an <a class="external-link" href="http://jsfcorner.blogspot.com/2011/01/custom-components.html" rel="nofollow">advanced topic</a>. In fact, many JSF developers have <em>never</em> created a custom component. In JSF 1.x, creating each custom component requires a lot of work: creating 3 Java classes (component, component renderer and component tag), registering the component in an XML file, and registering the tag in the .tld file. In JSF 2.x <em>composite components</em> can be created without too much work (if your needs can be met by combining existing components <em>and</em> you don't need any custom Java), but
you still have to use cumbersome <composite:interface> and <composite:implementation> tags in your component templates, and you have to list the composite components in the xml namespace declaration at the top of the pages where you are using them.</p><p>Creating true custom components in JSF 2.0 still requires several steps: create a component class (generally having the @FacesComponent annotation and extending UIComponentBase), create a renderer class (generally extending Renderer), add a <renderer> section to the facesconfig file, and create a *-taglib.xml file in the WEB_INF folder that defines the namespace, tag and component type of the custom component.</p><p>In contrast, with Tapestry, <a href="component-classes.html">creating custom components</a> is a <em>beginner</em> topic: it is expected to be a daily activity for developers, because it is so easy. In fact, the steps are the same as creating a page. All you have to do is create a (potentially empty)
Java class in a "components" sub-package, and create a template file containing (X)HTML markup in the corresponding "components" sub-folder within your package hierarchy under /src/main/resources. You <em>use</em> a custom component just like you use any built-in Tapestry component: <code><t:mycomponent></code>.</p><p>Because they're so easy to create, Tapestry applications tend to have a lot of custom components and much less repetition of HTML than most JSF applications.</p><h2 id="TapestryforJSFUsers-OtherReferences">Other References</h2><ul><li><a class="external-link" href="http://blog.tapestry5.de/wp-content/uploads/2010/06/JSF-2.0-vs-Tapestry-5.pdf" rel="nofollow">JavaServer Faces 2.0 vs. Tapestry 5: A Head-to-Head Comparison</a> slides by Igor Drobiazko, June 2010.</li><li><a class="external-link" href="http://docs.oracle.com/javaee/6/tutorial/doc/gkhxa.html" rel="nofollow">Composite Components: Advanced Topics and Example</a> part of <em>The Java EE 6 Tutorial</em>
from Oracle</li></ul><p> </p><p></p></div>
</div>
<div class="clearer"></div>
Modified: websites/production/tapestry/content/tapestry-inversion-of-control-faq.html
==============================================================================
--- websites/production/tapestry/content/tapestry-inversion-of-control-faq.html (original)
+++ websites/production/tapestry/content/tapestry-inversion-of-control-faq.html Sat Sep 16 01:54:19 2017
@@ -27,6 +27,16 @@
</title>
<link type="text/css" rel="stylesheet" href="/resources/space.css" />
+ <link href='/resources/highlighter/styles/shCoreCXF.css' rel='stylesheet' type='text/css' />
+ <link href='/resources/highlighter/styles/shThemeCXF.css' rel='stylesheet' type='text/css' />
+ <script src='/resources/highlighter/scripts/shCore.js' type='text/javascript'></script>
+ <script src='/resources/highlighter/scripts/shBrushJava.js' type='text/javascript'></script>
+ <script src='/resources/highlighter/scripts/shBrushXml.js' type='text/javascript'></script>
+ <script src='/resources/highlighter/scripts/shBrushPlain.js' type='text/javascript'></script>
+ <script>
+ SyntaxHighlighter.defaults['toolbar'] = false;
+ SyntaxHighlighter.all();
+ </script>
<link href="/styles/style.css" rel="stylesheet" type="text/css"/>
@@ -67,7 +77,59 @@
</div>
<div id="content">
- <div id="ConfluenceContent"><p><plain-text-body>{scrollbar}</plain-text-body></p><h2 id="TapestryInversionofControlFAQ-TapestryInversionofControlContainer">Tapestry Inversion of Control Container</h2><p>Main article: <a href="ioc.html">Tapestry IoC</a></p><p> </p><parameter ac:name="style">float:right</parameter><parameter ac:name="title">Related Articles</parameter><parameter ac:name="class">aui-label</parameter><rich-text-body><parameter ac:name="showLabels">false</parameter><parameter ac:name="showSpace">false</parameter><parameter ac:name="title">Related Articles</parameter><parameter ac:name="cql">label = "ioc" and space = currentSpace()</parameter></rich-text-body><h3 id="TapestryInversionofControlFAQ-WhydoIneedtodefineaninterfaceformyservices?Whycan'tIjustusetheclassitself?">Why do I need to define an interface for my services? Why can't I just use the class itself?</h3><p>First of all: you can do exactly this, but you lose some of the functionality that
Tapestry's IoC container provides.</p><p>The reason for the split is so that Tapestry can provide functionality for your service around the core service implementation. It does this by creating <em>proxies</em>: Java classes that implement the service interface. The methods of the proxy will ultimately invoke the methods of your service implementation.</p><p>One of the primary purposes for proxies is to encapsulate the service's life cycle: most services are singletons that are created <em>just in time</em>. Just in time means only as soon as you invoke a method. What's going on is that the life cycle proxy (the object that gets injected into pages, components or other service implementations) checks on each method invocation to see if the actual service exists yet. If not, it instantiates and configures it (using proper locking to ensure thread safety), then delegates the method invocation to the service.</p><p>If you bind a service class (not a service interface and class), then
the service is fully instantiated the first time it is injected, rather than at that first method invocation. Further, you can't use decorations or method advice on such a service.</p><p>The final reason for the service interface / implementation split is to nudge you towards always coding to an interface, which has manifest benefits for code structure, robustness, and testability.</p><h3 id="TapestryInversionofControlFAQ-Myservicestartsathread;howdoIknowwhentheapplicationisshuttingdown,tostopthatthread?">My service starts a thread; how do I know when the application is shutting down, to stop that thread?</h3><p>This same concern applies to any long-lived resource (a thread, a database connection, a JMS queue connection) that a service may hold onto. Your code needs to know when the application has been undeployed and shutdown. This is actually quite easy, by adding some post-injection logic to your implementation class.</p><parameter ac:name="controls">true</parameter><parameter ac
:name="linenumbers">true</parameter><plain-text-body>public class MyServiceImpl implements MyService
+ <div id="ConfluenceContent"><h2 id="TapestryInversionofControlFAQ-TapestryInversionofControlContainer">Tapestry Inversion of Control Container</h2><p>Main article: <a href="ioc.html">Tapestry IoC</a></p><p> </p><div class="aui-label" style="float:right" title="Related Articles">
+
+
+
+
+
+
+
+
+<h3>Related Articles</h3>
+
+<ul class="content-by-label"><li>
+ <div>
+ <span class="icon aui-icon aui-icon-small aui-iconfont-page-default" title="Page">Page:</span> </div>
+
+ <div class="details">
+ <a href="ioc.html">IOC</a>
+
+
+ </div>
+ </li><li>
+ <div>
+ <span class="icon aui-icon aui-icon-small aui-iconfont-page-default" title="Page">Page:</span> </div>
+
+ <div class="details">
+ <a href="ioc-cookbook.html">IoC cookbook</a>
+
+
+ </div>
+ </li><li>
+ <div>
+ <span class="icon aui-icon aui-icon-small aui-iconfont-page-default" title="Page">Page:</span> </div>
+
+ <div class="details">
+ <a href="tapestry-ioc-overview.html">Tapestry IoC Overview</a>
+
+
+ </div>
+ </li><li>
+ <div>
+ <span class="icon aui-icon aui-icon-small aui-iconfont-page-default" title="Page">Page:</span> </div>
+
+ <div class="details">
+ <a href="tapestry-inversion-of-control-faq.html">Tapestry Inversion of Control FAQ</a>
+
+
+ </div>
+ </li></ul>
+</div>
+
+
+<h3 id="TapestryInversionofControlFAQ-WhydoIneedtodefineaninterfaceformyservices?Whycan'tIjustusetheclassitself?">Why do I need to define an interface for my services? Why can't I just use the class itself?</h3><p>First of all: you can do exactly this, but you lose some of the functionality that Tapestry's IoC container provides.</p><p>The reason for the split is so that Tapestry can provide functionality for your service around the core service implementation. It does this by creating <em>proxies</em>: Java classes that implement the service interface. The methods of the proxy will ultimately invoke the methods of your service implementation.</p><p>One of the primary purposes for proxies is to encapsulate the service's life cycle: most services are singletons that are created <em>just in time</em>. Just in time means only as soon as you invoke a method. What's going on is that the life cycle proxy (the object that gets injected into pages, components or other service implementation
s) checks on each method invocation to see if the actual service exists yet. If not, it instantiates and configures it (using proper locking to ensure thread safety), then delegates the method invocation to the service.</p><p>If you bind a service class (not a service interface and class), then the service is fully instantiated the first time it is injected, rather than at that first method invocation. Further, you can't use decorations or method advice on such a service.</p><p>The final reason for the service interface / implementation split is to nudge you towards always coding to an interface, which has manifest benefits for code structure, robustness, and testability.</p><h3 id="TapestryInversionofControlFAQ-Myservicestartsathread;howdoIknowwhentheapplicationisshuttingdown,tostopthatthread?">My service starts a thread; how do I know when the application is shutting down, to stop that thread?</h3><p>This same concern applies to any long-lived resource (a thread, a database connec
tion, a JMS queue connection) that a service may hold onto. Your code needs to know when the application has been undeployed and shutdown. This is actually quite easy, by adding some post-injection logic to your implementation class.</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
+<pre class="brush: java; gutter: true; theme: Default" style="font-size:12px;">public class MyServiceImpl implements MyService
{
private boolean shuttingDown;
@@ -94,7 +156,8 @@
});
}
}
-</plain-text-body><p>After Tapestry invokes the constructor of the service implementation, and after it performs any field injections, it invokes post injection methods. The methods must be public and return void. Parameters to a post injection method represent further injections ... in the above example, the RegistryShutdownHub is injected into the PostInjection method, since it is only used inside that one method.</p><rich-text-body><p>It is <strong>not</strong> recommended that MyServiceImpl take RegistryShutdownHub as a constructor parameter and register itself as a listener inside the constructor. Doing so is an example of <a class="external-link" href="http://www.ibm.com/developerworks/java/library/j-jtp0618.html" rel="nofollow">unsafe publishing</a>, a remote but potential thread safety issue.</p></rich-text-body><p>This same technique will work for any kind of resource that must be cleaned up or destroyed when the registry shuts down.</p><rich-text-body><p>Be careful not to
invoke methods on any service proxy objects as they will also be shutting down with the Registry. A RegistryShutdownListener should not be reliant on anything outside of itself.</p></rich-text-body><h3 id="TapestryInversionofControlFAQ-HowdoImakemyservicestartupwiththerestoftheapplication,ratherthanlazily?">How do I make my service startup with the rest of the application, rather than lazily?</h3><p>Tapestry services are designed to be <em>lazy</em>; they are only fully realized when needed: when the first method on the service interface is invoked.</p><p>Sometimes a service does extra work that is desirable at application startup: examples may be registering message handlers with a JMS implementation, or setting up indexing. Since the service's constructor (or <a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/ioc/annotations/PostInjection.html">@PostInjection</a> methods) are not invoked until the service is realized.</p><p>The solutio
n is the <a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/ioc/annotations/EagerLoad.html">@EagerLoad</a> annotation; service implementation classes marked with this annotation are loaded when the Registry is first startup, rather than lazily.<plain-text-body>{scrollbar}</plain-text-body></p></div>
+</pre>
+</div></div><p>After Tapestry invokes the constructor of the service implementation, and after it performs any field injections, it invokes post injection methods. The methods must be public and return void. Parameters to a post injection method represent further injections ... in the above example, the RegistryShutdownHub is injected into the PostInjection method, since it is only used inside that one method.</p><div class="confluence-information-macro confluence-information-macro-warning"><span class="aui-icon aui-icon-small aui-iconfont-error confluence-information-macro-icon"></span><div class="confluence-information-macro-body"><p>It is <strong>not</strong> recommended that MyServiceImpl take RegistryShutdownHub as a constructor parameter and register itself as a listener inside the constructor. Doing so is an example of <a class="external-link" href="http://www.ibm.com/developerworks/java/library/j-jtp0618.html" rel="nofollow">unsafe publishing</a>, a remote but potential thr
ead safety issue.</p></div></div><p>This same technique will work for any kind of resource that must be cleaned up or destroyed when the registry shuts down.</p><div class="confluence-information-macro confluence-information-macro-note"><span class="aui-icon aui-icon-small aui-iconfont-warning confluence-information-macro-icon"></span><div class="confluence-information-macro-body"><p>Be careful not to invoke methods on any service proxy objects as they will also be shutting down with the Registry. A RegistryShutdownListener should not be reliant on anything outside of itself.</p></div></div><h3 id="TapestryInversionofControlFAQ-HowdoImakemyservicestartupwiththerestoftheapplication,ratherthanlazily?">How do I make my service startup with the rest of the application, rather than lazily?</h3><p>Tapestry services are designed to be <em>lazy</em>; they are only fully realized when needed: when the first method on the service interface is invoked.</p><p>Sometimes a service does extra work
that is desirable at application startup: examples may be registering message handlers with a JMS implementation, or setting up indexing. Since the service's constructor (or <a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/ioc/annotations/PostInjection.html">@PostInjection</a> methods) are not invoked until the service is realized.</p><p>The solution is the <a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/ioc/annotations/EagerLoad.html">@EagerLoad</a> annotation; service implementation classes marked with this annotation are loaded when the Registry is first startup, rather than lazily.</p></div>
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