Modified: websites/production/tapestry/content/logging-in-tapestry.html ============================================================================== --- websites/production/tapestry/content/logging-in-tapestry.html (original) +++ websites/production/tapestry/content/logging-in-tapestry.html Sat Jan 18 18:21:05 2014 @@ -29,6 +29,7 @@ <link href='http://cxf.apache.org/resources/highlighter/styles/shThemeCXF.css' rel='stylesheet' type='text/css' /> <script src='http://cxf.apache.org/resources/highlighter/scripts/shCore.js' type='text/javascript'></script> <script src='http://cxf.apache.org/resources/highlighter/scripts/shBrushJava.js' type='text/javascript'></script> + <script src='http://cxf.apache.org/resources/highlighter/scripts/shBrushXml.js' type='text/javascript'></script> <script type="text/javascript"> SyntaxHighlighter.defaults['toolbar'] = false; SyntaxHighlighter.all(); @@ -77,9 +78,7 @@ table.ScrollbarTable td.ScrollbarParent table.ScrollbarTable td.ScrollbarNextName {text-align: right;border: none;} table.ScrollbarTable td.ScrollbarNextIcon {text-align: center;width: 16px;border: none;} -/*]]>*/</style><div class="Scrollbar"><table class="ScrollbarTable"><tr><td colspan="1" rowspan="1" class="ScrollbarPrevIcon"><a shape="rect" href="parallel-execution.html"><img align="middle" border="0" src="https://cwiki.apache.org/confluence/images/icons/back_16.gif"; width="16" height="16"></a></td><td colspan="1" rowspan="1" class="ScrollbarPrevName" width="33%"><a shape="rect" href="parallel-execution.html">Parallel Execution</a> </td><td colspan="1" rowspan="1" class="ScrollbarParent" width="33%"><sup><a shape="rect" href="ioc.html"><img align="middle" border="0" src="https://cwiki.apache.org/confluence/images/icons/up_16.gif"; width="8" height="8"></a></sup><a shape="rect" href="ioc.html">IoC</a></td><td colspan="1" rowspan="1" class="ScrollbarNextName" width="33%"> <a shape="rect" href="using-jsr-330-standard-annotations.html">Using JSR 330 standard annotations</a></td><td colspan="1" rowspan="1" class="ScrollbarNextIcon"><a shape="rect" href="using-jsr-330-standard -annotations.html"><img align="middle" border="0" src="https://cwiki.apache.org/confluence/images/icons/forwd_16.gif"; width="16" height="16"></a></td></tr></table></div> - -<div class="navmenu" style="float:right; background:#eee; margin:3px; padding:3px"> +/*]]>*/</style><div class="Scrollbar"><table class="ScrollbarTable"><tr><td colspan="1" rowspan="1" class="ScrollbarPrevIcon"><a shape="rect" href="parallel-execution.html"><img align="middle" border="0" src="https://cwiki.apache.org/confluence/images/icons/back_16.gif"; width="16" height="16"></a></td><td colspan="1" rowspan="1" class="ScrollbarPrevName" width="33%"><a shape="rect" href="parallel-execution.html">Parallel Execution</a> </td><td colspan="1" rowspan="1" class="ScrollbarParent" width="33%"><sup><a shape="rect" href="ioc.html"><img align="middle" border="0" src="https://cwiki.apache.org/confluence/images/icons/up_16.gif"; width="8" height="8"></a></sup><a shape="rect" href="ioc.html">IoC</a></td><td colspan="1" rowspan="1" class="ScrollbarNextName" width="33%"> <a shape="rect" href="using-jsr-330-standard-annotations.html">Using JSR 330 standard annotations</a></td><td colspan="1" rowspan="1" class="ScrollbarNextIcon"><a shape="rect" href="using-jsr-330-standard -annotations.html"><img align="middle" border="0" src="https://cwiki.apache.org/confluence/images/icons/forwd_16.gif"; width="16" height="16"></a></td></tr></table></div><div class="navmenu" style="float:right; background:#eee; margin:3px; padding:3px"> <h3>Related Articles</h3> <ul class="content-by-label"><li> <div> @@ -100,43 +99,7 @@ table.ScrollbarTable td.ScrollbarNextIco </div> </li></ul> -</div> - -<h1 id="LogginginTapestry-LogginginTapestry">Logging in Tapestry</h1> - -<p>Logging in Tapestry is based on the <a shape="rect" class="external-link" href="http://www.slf4j.org/"; >Simple Logging Facade for Java (SLF4J)</a>. You can think of SLF4J as a leaner, meaner replacement for <a shape="rect" class="external-link" href="http://commons.apache.org/logging/";>commons-logging</a>.</p> - -<p>In theory, SLF4J is a wrapper around any of a number of logging systems, including <a shape="rect" class="external-link" href="http://logging.apache.org/log4j/1.2/";>Log4J</a> or the built-in JDK logging. In practice, it is almost always used with Log4J and no additional build configuration is needed.</p> - -<p>Your application <em>will</em> need to provide a <strong>log4j.properties</strong> file (or its XML equivalent). See <a shape="rect" class="external-link" href="http://logging.apache.org/log4j/1.2/manual.html";>the Log4J manual</a> for more information.</p> - -<h1 id="LogginginTapestry-AccessingLoggers">Accessing Loggers</h1> - -<p>Loggers are a special kind of resource that is injected into a service. In Tapestry IoC, Loggers an be injected into service constructors, or into service builder methods.</p> - -<p>In Tapestry Core (the web framework), Loggers for components can be injected into component fields.</p> - -<p>This often confuses people, because the standard idiom is to create a Logger based on the class name and inject it into a static field. In Tapestry, the Logger is created on your code's behalf and provided to you, and stored into a final private field.</p> - -<p>In terms of separation of concerns, Tapestry's approach is superior ... the concern of creating loggers is offloaded into the framework, and you code retains the concern of actually logging useful information. However this is largely theoretical.</p> - -<p>For a pragmatic standpoint, injecting Loggers makes it easier to test <em>logging</em> code using the same techniques used to test other code: via the injection of Mock Object implementations of the Logger interface. This is something to consider when writing your own services, components and test.</p> - -<h1 id="LogginginTapestry-ServiceLogging">Service Logging</h1> - -<p>Tapestry uses the same loggers that are injected into services; it logs, at debug level, details about the construction of the service (and the proxy for the service), including details such as methods invoked. </p> - -<h1 id="LogginginTapestry-OperationTracker">Operation Tracker</h1> - -<p>The OperationTracker is a resource available throughout Tapestry that is used to track what Tapestry is doing at any given time. Normally, this information is only used when reporting errors, as it gives an indication of what Tapestry was doing leading up to the point where the exception occurred.</p> - -<p>Starting in Tapestry 5.3, you may also enable debug logging for <code>org.apache.tapestry5.ioc.Registry</code> to see voluminous details on creation of proxies, services, injections, and so forth. It also tracks creation of pages and components, triggering of component events, handling of return values from event handler methods, and many (many!) other details.</p> - -<p>The logging even identifies how long each operation takes. This can be useful for understanding what is going on in a Tapestry application during the processing of the request, it can also be useful when tracking down performance issues. </p> - -<p>An example from the startup of a Tapestry application:</p> - -<div class="preformatted panel" style="border-width: 1px;"><div class="preformattedContent panelContent"> +</div><h1 id="LogginginTapestry-LogginginTapestry">Logging in Tapestry</h1><p>Logging in Tapestry is based on the <a shape="rect" class="external-link" href="http://www.slf4j.org/"; >Simple Logging Facade for Java (SLF4J)</a>. You can think of SLF4J as a leaner, meaner replacement for <a shape="rect" class="external-link" href="http://commons.apache.org/logging/";>commons-logging</a>.</p><p>In theory, SLF4J is a wrapper around any of a number of logging systems, including <a shape="rect" class="external-link" href="http://logging.apache.org/log4j/1.2/";>Log4J</a> or the built-in JDK logging. In practice, it is almost always used with Log4J and no additional build configuration is needed.</p><p>Your application <em>will</em> need to provide a <strong>log4j.properties</strong> file (or its XML equivalent). See <a shape="rect" class="external-link" href="http://logging.apache.org/log4j/1.2/manual.html";>the Log4J manual</a> for more information.</p><h1 id="LogginginTapestry-AccessingLogger s">Accessing Loggers</h1><p>Loggers are a special kind of resource that is injected into a service. In Tapestry IoC, Loggers an be injected into service constructors, or into service builder methods.</p><p>In Tapestry Core (the web framework), Loggers for components can be injected into component fields.</p><p>This often confuses people, because the standard idiom is to create a Logger based on the class name and inject it into a static field. In Tapestry, the Logger is created on your code's behalf and provided to you, and stored into a final private field.</p><p>In terms of separation of concerns, Tapestry's approach is superior ... the concern of creating loggers is offloaded into the framework, and you code retains the concern of actually logging useful information. However this is largely theoretical.</p><p>For a pragmatic standpoint, injecting Loggers makes it easier to test <em>logging</em> code using the same techniques used to test other code: via the injection of Mock Obje ct implementations of the Logger interface. This is something to consider when writing your own services, components and test.</p><h1 id="LogginginTapestry-ServiceLogging">Service Logging</h1><p>Tapestry uses the same loggers that are injected into services; it logs, at debug level, details about the construction of the service (and the proxy for the service), including details such as methods invoked.</p><h1 id="LogginginTapestry-OperationTracker">Operation Tracker</h1><p>The OperationTracker is a resource available throughout Tapestry that is used to track what Tapestry is doing at any given time. Normally, this information is only used when reporting errors, as it gives an indication of what Tapestry was doing leading up to the point where the exception occurred.</p><p>Starting in Tapestry 5.3, you may also enable debug logging for <code>org.apache.tapestry5.ioc.Registry</code> to see voluminous details on creation of proxies, services, injections, and so forth. It also tracks cr eation of pages and components, triggering of component events, handling of return values from event handler methods, and many (many!) other details.</p><p>The logging even identifies how long each operation takes. This can be useful for understanding what is going on in a Tapestry application during the processing of the request, it can also be useful when tracking down performance issues.</p><p>An example from the startup of a Tapestry application:</p><div class="preformatted panel" style="border-width: 1px;"><div class="preformattedContent panelContent"> <pre>[INFO] RegistryBuilder Adding module definition for class org.apache.tapestry5.services.TapestryModule [INFO] RegistryBuilder Adding module definition for class org.apache.tapestry5.internal.services.InternalModule [INFO] RegistryBuilder Adding module definition for class org.apache.tapestry5.services.assets.AssetsModule @@ -182,17 +145,7 @@ table.ScrollbarTable td.ScrollbarNextIco [DEBUG] Registry [ 11] --> Determining injection value for parameter #2 (org.apache.tapestry5.ioc.ObjectProvider) . . . </pre> -</div></div> - -<h1 id="LogginginTapestry-ConfiguringTapestryforotherLoggingToolkits">Configuring Tapestry for other Logging Toolkits</h1> - -<p>The default configuration uses Log4J.</p> - -<p>If you need to use another logging system, that can be accomplished using Maven dependency control.</p> - -<p>You can exclude some of the dependencies that Tapestry introduces, and replace them with your own. For example, to switch over to JDK logging, update your pom as follows:</p> - -<div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl"> +</div></div><h1 id="LogginginTapestry-ConfiguringTapestryforotherLoggingToolkits">Configuring Tapestry for other Logging Toolkits</h1><p>The default configuration uses Log4J.</p><p>If you need to use another logging system, that can be accomplished using Maven dependency control.</p><p>You can exclude some of the dependencies that Tapestry introduces, and replace them with your own. For example, to switch over to JDK logging, update your pom as follows:</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl"> <script class="theme: Default; brush: xml; gutter: false" type="syntaxhighlighter"><![CDATA[ <dependencies> <dependency> @@ -221,13 +174,7 @@ table.ScrollbarTable td.ScrollbarNextIco </dependency> </dependencies> ]]></script> -</div></div> - -<p>This pulls out the log4j support normally included with Tapestry, and replaces it with the SLF4J library that wraps around JDK 1.4 logging.</p> - -<p>In all likelihood, you'll replace <em>tapestry-ioc</em> with <em>tapestry-core</em> (assuming you are building a web application using Tapestry, rather than using Tapestry IoC as part of some other application). And, of course, version numbers change all the time!</p> - -<style type="text/css">/*<![CDATA[*/ +</div></div><p>This pulls out the log4j support normally included with Tapestry, and replaces it with the SLF4J library that wraps around JDK 1.4 logging.</p><p>In all likelihood, you'll replace <em>tapestry-ioc</em> with <em>tapestry-core</em> (assuming you are building a web application using Tapestry, rather than using Tapestry IoC as part of some other application). And, of course, version numbers change all the time!</p><style type="text/css">/*<![CDATA[*/ table.ScrollbarTable {border: none;padding: 3px;width: 100%;padding: 3px;margin: 0px;background-color: #f0f0f0} table.ScrollbarTable td.ScrollbarPrevIcon {text-align: center;width: 16px;border: none;} table.ScrollbarTable td.ScrollbarPrevName {text-align: left;border: none;}
Modified: websites/production/tapestry/content/overriding-exception-reporting.html ============================================================================== --- websites/production/tapestry/content/overriding-exception-reporting.html (original) +++ websites/production/tapestry/content/overriding-exception-reporting.html Sat Jan 18 18:21:05 2014 @@ -29,6 +29,7 @@ <link href='http://cxf.apache.org/resources/highlighter/styles/shThemeCXF.css' rel='stylesheet' type='text/css' /> <script src='http://cxf.apache.org/resources/highlighter/scripts/shCore.js' type='text/javascript'></script> <script src='http://cxf.apache.org/resources/highlighter/scripts/shBrushJava.js' type='text/javascript'></script> + <script src='http://cxf.apache.org/resources/highlighter/scripts/shBrushXml.js' type='text/javascript'></script> <script type="text/javascript"> SyntaxHighlighter.defaults['toolbar'] = false; SyntaxHighlighter.all(); @@ -77,19 +78,14 @@ table.ScrollbarTable td.ScrollbarParent table.ScrollbarTable td.ScrollbarNextName {text-align: right;border: none;} table.ScrollbarTable td.ScrollbarNextIcon {text-align: center;width: 16px;border: none;} -/*]]>*/</style><div class="Scrollbar"><table class="ScrollbarTable"><tr><td colspan="1" rowspan="1" class="ScrollbarPrevIcon"><a shape="rect" href="default-parameter.html"><img align="middle" border="0" src="https://cwiki.apache.org/confluence/images/icons/back_16.gif"; width="16" height="16"></a></td><td colspan="1" rowspan="1" class="ScrollbarPrevName" width="33%"><a shape="rect" href="default-parameter.html">Default Parameter</a> </td><td colspan="1" rowspan="1" class="ScrollbarParent" width="33%"><sup><a shape="rect" href="cookbook.html"><img align="middle" border="0" src="https://cwiki.apache.org/confluence/images/icons/up_16.gif"; width="8" height="8"></a></sup><a shape="rect" href="cookbook.html">Cookbook</a></td><td colspan="1" rowspan="1" class="ScrollbarNextName" width="33%"> <a shape="rect" href="supporting-informal-parameters.html">Supporting Informal Parameters</a></td><td colspan="1" rowspan="1" class="ScrollbarNextIcon"><a shape="rect" href="supporting-informa l-parameters.html"><img align="middle" border="0" src="https://cwiki.apache.org/confluence/images/icons/forwd_16.gif"; width="16" height="16"></a></td></tr></table></div> -<p></p> - -<h1 id="OverridingExceptionReporting-OverridingExceptionReporting">Overriding Exception Reporting</h1> - -<div class="navmenu" style="float:right; background:#eee; margin:3px; padding:3px"> +/*]]>*/</style><div class="Scrollbar"><table class="ScrollbarTable"><tr><td colspan="1" rowspan="1" class="ScrollbarPrevIcon"><a shape="rect" href="default-parameter.html"><img align="middle" border="0" src="https://cwiki.apache.org/confluence/images/icons/back_16.gif"; width="16" height="16"></a></td><td colspan="1" rowspan="1" class="ScrollbarPrevName" width="33%"><a shape="rect" href="default-parameter.html">Default Parameter</a> </td><td colspan="1" rowspan="1" class="ScrollbarParent" width="33%"><sup><a shape="rect" href="cookbook.html"><img align="middle" border="0" src="https://cwiki.apache.org/confluence/images/icons/up_16.gif"; width="8" height="8"></a></sup><a shape="rect" href="cookbook.html">Cookbook</a></td><td colspan="1" rowspan="1" class="ScrollbarNextName" width="33%"> <a shape="rect" href="supporting-informal-parameters.html">Supporting Informal Parameters</a></td><td colspan="1" rowspan="1" class="ScrollbarNextIcon"><a shape="rect" href="supporting-informa l-parameters.html"><img align="middle" border="0" src="https://cwiki.apache.org/confluence/images/icons/forwd_16.gif"; width="16" height="16"></a></td></tr></table></div><h1 id="OverridingExceptionReporting-OverridingExceptionReporting">Overriding Exception Reporting</h1><div class="navmenu" style="float:right; background:#eee; margin:3px; padding:3px"> <h3>Related Articles</h3> <ul class="content-by-label"><li> <div> <span class="icon icon-page" title="Page">Page:</span> </div> <div class="details"> - <a shape="rect" href="overriding-exception-reporting.html">Overriding Exception Reporting</a> + <a shape="rect" href="error-page-recipe.html">Error Page Recipe</a> </div> @@ -98,7 +94,7 @@ table.ScrollbarTable td.ScrollbarNextIco <span class="icon icon-page" title="Page">Page:</span> </div> <div class="details"> - <a shape="rect" href="error-page-recipe.html">Error Page Recipe</a> + <a shape="rect" href="specific-errors-faq.html">Specific Errors FAQ</a> </div> @@ -107,24 +103,13 @@ table.ScrollbarTable td.ScrollbarNextIco <span class="icon icon-page" title="Page">Page:</span> </div> <div class="details"> - <a shape="rect" href="specific-errors-faq.html">Specific Errors FAQ</a> + <a shape="rect" href="overriding-exception-reporting.html">Overriding Exception Reporting</a> </div> </li></ul> -</div> - -<p>One of Tapestry's best features is its comprehensive exception reporting. The level of detail is impressive and useful.</p> - -<p>Of course, one of the first questions anyone asks is "How do I turn it off?" This exception reporting is very helpful for developers but its easy to see it as terrifying for potential users. Not that you'd have have runtime exceptions in production, of course, but even so ...</p> - -<h2 id="OverridingExceptionReporting-Version1:ReplacingtheExceptionReportPage">Version 1: Replacing the Exception Report Page</h2> - -<p>Let's start with a page that fires an exception from an event handler method.</p> - -<div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1px;"><b>Index.tml</b></div><div class="codeContent panelContent pdl"> -<script class="theme: Default; brush: xml; gutter: false" type="syntaxhighlighter"><![CDATA[ -<html xmlns:t="http://tapestry.apache.org/schema/tapestry_5_1_0.xsd"> +</div><p>One of Tapestry's best features is its comprehensive exception reporting. The level of detail is impressive and useful.</p><p>Of course, one of the first questions anyone asks is "How do I turn it off?" This exception reporting is very helpful for developers but its easy to see it as terrifying for potential users. Not that you'd have have runtime exceptions in production, of course, but even so ...</p><h2 id="OverridingExceptionReporting-Version1:ReplacingtheExceptionReportPage">Version 1: Replacing the Exception Report Page</h2><p>Let's start with a page that fires an exception from an event handler method.</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1px;"><b>Index.tml</b></div><div class="codeContent panelContent pdl"> +<script class="theme: Default; brush: xml; gutter: false" type="syntaxhighlighter"><![CDATA[<html xmlns:t="http://tapestry.apache.org/schema/tapestry_5_1_0.xsd"> <head> <title>Index</title> </head> @@ -135,11 +120,8 @@ table.ScrollbarTable td.ScrollbarNextIco </body> </html> ]]></script> -</div></div> - -<div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1px;"><b>Index.java</b></div><div class="codeContent panelContent pdl"> -<script class="theme: Default; brush: java; gutter: false" type="syntaxhighlighter"><![CDATA[ -package com.example.tapestry2523.pages; +</div></div><div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1px;"><b>Index.java</b></div><div class="codeContent panelContent pdl"> +<script class="theme: Default; brush: java; gutter: false" type="syntaxhighlighter"><![CDATA[package com.example.tapestry2523.pages; public class Index { @@ -149,19 +131,8 @@ public class Index } } ]]></script> -</div></div> - -<p>With production mode disabled, clicking the link displays the default exception report page:</p> - -<p><img class="confluence-embedded-image" src="https://cwiki.apache.org/confluence/download/attachments/20645557/error1.png?version=1&modificationDate=1273638562000&api=v2"; data-image-src="/confluence/download/attachments/20645557/error1.png?version=1&modificationDate=1273638562000&api=v2" title="Default exception report"></p> - -<p>The easy way to override the exception report is to provide an ExceptionReport page that overrides the one provided with the framework.</p> - -<p>This is as easy as providing a page named "ExceptionReport". It must implement the <a shape="rect" class="external-link" href="http://tapestry.apache.org/tapestry5/apidocs/org/apache/tapestry5/services/ExceptionReporter.html";>ExceptionReporter</a> interface.</p> - -<div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1px;"><b>ExceptionReport.tml</b></div><div class="codeContent panelContent pdl"> -<script class="theme: Default; brush: xml; gutter: false" type="syntaxhighlighter"><![CDATA[ -<html xmlns:t="http://tapestry.apache.org/schema/tapestry_5_1_0.xsd"> +</div></div><p>With production mode disabled, clicking the link displays the default exception report page:</p><p><img class="confluence-embedded-image" src="https://cwiki.apache.org/confluence/download/attachments/20645557/error1.png?version=1&modificationDate=1273638562000&api=v2"; data-image-src="/confluence/download/attachments/20645557/error1.png?version=1&modificationDate=1273638562000&api=v2" title="Default exception report"></p><p>The easy way to override the exception report is to provide an ExceptionReport page that overrides the one provided with the framework.</p><p>This is as easy as providing a page named "ExceptionReport". It must implement the <a shape="rect" class="external-link" href="http://tapestry.apache.org/tapestry5/apidocs/org/apache/tapestry5/services/ExceptionReporter.html";>ExceptionReporter</a> interface.</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1px;"><b>Exc eptionReport.tml</b></div><div class="codeContent panelContent pdl"> +<script class="theme: Default; brush: xml; gutter: false" type="syntaxhighlighter"><![CDATA[<html xmlns:t="http://tapestry.apache.org/schema/tapestry_5_1_0.xsd"> <head> <title>Exception</title> </head> @@ -182,11 +153,8 @@ public class Index </html> ]]></script> -</div></div> - -<div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1px;"><b>ExceptionReport.java</b></div><div class="codeContent panelContent pdl"> -<script class="theme: Default; brush: java; gutter: false" type="syntaxhighlighter"><![CDATA[ -package com.example.tapestry2523.pages; +</div></div><div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1px;"><b>ExceptionReport.java</b></div><div class="codeContent panelContent pdl"> +<script class="theme: Default; brush: java; gutter: false" type="syntaxhighlighter"><![CDATA[package com.example.tapestry2523.pages; import org.apache.tapestry5.annotations.Property; import org.apache.tapestry5.services.ExceptionReporter; @@ -202,37 +170,16 @@ public class ExceptionReport implements } } ]]></script> -</div></div> - -<p>The end result is a customized exception report page.</p> - -<p><img class="confluence-embedded-image" src="https://cwiki.apache.org/confluence/download/attachments/20645557/error2.png?version=1&modificationDate=1273638562000&api=v2"; data-image-src="/confluence/download/attachments/20645557/error2.png?version=1&modificationDate=1273638562000&api=v2" title="Customized Exception Report Page"></p> - - -<h2 id="OverridingExceptionReporting-Version2:OverridingtheRequestExceptionHandler">Version 2: Overriding the RequestExceptionHandler</h2> - -<p>The previous example will display a link back to the Index page of the application. Another alternative is to display the error <on> the Index page. This requires a different approach: overriding the service responsible for reporting request exceptions.</p> - -<p>The service <a shape="rect" class="external-link" href="http://tapestry.apache.org/tapestry5/apidocs/org/apache/tapestry5/services/RequestExceptionHandler.html";>RequestExceptionHandler</a> is responsible for this.</p> - -<p>By replacing the default implementation of this service with our own implementation, we can take control over exactly what happens when a request exception occurs.</p> - -<p>We'll do this in two steps. First, we'll extend the Index page to serve as an ExceptionReporter. Second, we'll override the default RequestExceptionHandler to use the Index page instead of the ExceptionReport page. Of course, this is just one approach.</p> - -<div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1px;"><b>Index.tml (partial)</b></div><div class="codeContent panelContent pdl"> -<script class="theme: Default; brush: xml; gutter: false" type="syntaxhighlighter"><![CDATA[ - <t:if test="message"> +</div></div><p>The end result is a customized exception report page.</p><p><img class="confluence-embedded-image" src="https://cwiki.apache.org/confluence/download/attachments/20645557/error2.png?version=1&modificationDate=1273638562000&api=v2"; data-image-src="/confluence/download/attachments/20645557/error2.png?version=1&modificationDate=1273638562000&api=v2" title="Customized Exception Report Page"></p><h2 id="OverridingExceptionReporting-Version2:OverridingtheRequestExceptionHandler">Version 2: Overriding the RequestExceptionHandler</h2><p>The previous example will display a link back to the Index page of the application. Another alternative is to display the error <on> the Index page. This requires a different approach: overriding the service responsible for reporting request exceptions.</p><p>The service <a shape="rect" class="external-link" href="http://tapestry.apache.org/tapestry5/apidocs/org/apache/tapestry5/services/RequestExceptionHandler.html";>Reque stExceptionHandler</a> is responsible for this.</p><p>By replacing the default implementation of this service with our own implementation, we can take control over exactly what happens when a request exception occurs.</p><p>We'll do this in two steps. First, we'll extend the Index page to serve as an ExceptionReporter. Second, we'll override the default RequestExceptionHandler to use the Index page instead of the ExceptionReport page. Of course, this is just one approach.</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1px;"><b>Index.tml (partial)</b></div><div class="codeContent panelContent pdl"> +<script class="theme: Default; brush: xml; gutter: false" type="syntaxhighlighter"><![CDATA[ <t:if test="message"> <p> An unexpected exception has occurred: <strong>${message}</strong> </p> </t:if> ]]></script> -</div></div> - -<div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1px;"><b>Index.java</b></div><div class="codeContent panelContent pdl"> -<script class="theme: Default; brush: java; gutter: false" type="syntaxhighlighter"><![CDATA[ -public class Index implements ExceptionReporter +</div></div><div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1px;"><b>Index.java</b></div><div class="codeContent panelContent pdl"> +<script class="theme: Default; brush: java; gutter: false" type="syntaxhighlighter"><![CDATA[public class Index implements ExceptionReporter { @Property @Persist(PersistenceConstants.FLASH) @@ -249,17 +196,8 @@ public class Index implements ExceptionR } } ]]></script> -</div></div> - -<p>The above defines a new property, message, on the Index page. The @Persist annotation indicates that values assigned to the field will persist from one request to another. The use of FLASH for the persistence strategy indicates that the value will be used until the next time the page renders, then the value will be discarded.</p> - -<p>The message property is set from the thrown runtime exception.</p> - -<p>The remaining changes take place inside AppModule.</p> - -<div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1px;"><b>AppModule.java (partial)</b></div><div class="codeContent panelContent pdl"> -<script class="theme: Default; brush: java; gutter: false" type="syntaxhighlighter"><![CDATA[ - public RequestExceptionHandler buildAppRequestExceptionHandler( +</div></div><p>The above defines a new property, message, on the Index page. The @Persist annotation indicates that values assigned to the field will persist from one request to another. The use of FLASH for the persistence strategy indicates that the value will be used until the next time the page renders, then the value will be discarded.</p><p>The message property is set from the thrown runtime exception.</p><p>The remaining changes take place inside AppModule.</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1px;"><b>AppModule.java (partial)</b></div><div class="codeContent panelContent pdl"> +<script class="theme: Default; brush: java; gutter: false" type="syntaxhighlighter"><![CDATA[ public RequestExceptionHandler buildAppRequestExceptionHandler( final Logger logger, final ResponseRenderer renderer, final ComponentSource componentSource) @@ -288,33 +226,8 @@ public class Index implements ExceptionR configuration.add(RequestExceptionHandler.class, handler); } ]]></script> -</div></div> - -<p>First we define the new service using a service builder method. This is an alternative to the <code>bind()</code> method; we define the service, its interface type (the return type of the method) and the service id (the part that follows "build" is the method name) and provide the implementation inline. A service builder method must return the service implementation, here implemented as an inner class.</p> - -<p>The Logger resource that is passed into the builder method is the Logger appropriate for the service. ResponseRenderer and ComponentSource are two services defined by Tapestry.</p> - -<p>With this in place, there are now two different services that implement the RequestExceptionHandler interface: the default one built into Tapestry (whose service id is "RequestExceptionHandler") and the new one defined in this module, "AppRequestExceptionHandler"). Without a little more work, Tapestry will be unable to determine which one to use when an exception does occur.</p> - -<p>Tapestry has a pipeline for resolving injected dependencies; the ServiceOverride service is one part of that pipeline. Contributions to it are used to override an existing service, when the injection is exclusively by type. </p> - -<p>Here we inject the AppRequestExceptionHandler service and contribute it as the override for type RequestExceptionHandler. The @Local annotation is used to select the RequestHandler service defined by this module, AppModule. Once contributed into ServiceOverride, it becomes the default service injected throughout the Registry.</p> - -<p>This finally brings us to the point where we can see the result:</p> - -<p><img class="confluence-embedded-image" src="https://cwiki.apache.org/confluence/download/attachments/20645557/error3.png?version=1&modificationDate=1273638562000&api=v2"; data-image-src="/confluence/download/attachments/20645557/error3.png?version=1&modificationDate=1273638562000&api=v2" title="Errors show on Index page"></p> - -<h2 id="OverridingExceptionReporting-Version3:DecoratingtheRequestExceptionHandler">Version 3: Decorating the RequestExceptionHandler</h2> - -<p>A third option is available: we don't define a <em>new</em> service, but instead <em>decorate</em> the existing RequestExceptionHandler service. This approach means we don't have to make a contribution to the ServiceOverride service.</p> - -<p>Service decoration is a powerful facility of Tapestry that is generally used to "wrap" an existing service with an interceptor that provides new functionality such as logging, security, transaction management or other cross-cutting concerns. The interceptor is an object that implements the same interface as the service being decorated, and usually delegates method invocations to it.</p> - -<p>However, there's no requirement that an interceptor for a service actually invoke methods on the service; here we contribute a new implementation that <em>replaces</em> the original:</p> - -<div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1px;"><b>AppModule.java (partial)</b></div><div class="codeContent panelContent pdl"> -<script class="theme: Default; brush: java; gutter: false" type="syntaxhighlighter"><![CDATA[ - public RequestExceptionHandler decorateRequestExceptionHandler( +</div></div><p>First we define the new service using a service builder method. This is an alternative to the <code>bind()</code> method; we define the service, its interface type (the return type of the method) and the service id (the part that follows "build" is the method name) and provide the implementation inline. A service builder method must return the service implementation, here implemented as an inner class.</p><p>The Logger resource that is passed into the builder method is the Logger appropriate for the service. ResponseRenderer and ComponentSource are two services defined by Tapestry.</p><p>With this in place, there are now two different services that implement the RequestExceptionHandler interface: the default one built into Tapestry (whose service id is "RequestExceptionHandler") and the new one defined in this module, "AppRequestExceptionHandler"). Without a little more work, Tapestry will be unable to determine which one to use when an exception does occur.</p><p>Tap estry has a pipeline for resolving injected dependencies; the ServiceOverride service is one part of that pipeline. Contributions to it are used to override an existing service, when the injection is exclusively by type.</p><p>Here we inject the AppRequestExceptionHandler service and contribute it as the override for type RequestExceptionHandler. The @Local annotation is used to select the RequestHandler service defined by this module, AppModule. Once contributed into ServiceOverride, it becomes the default service injected throughout the Registry.</p><p>This finally brings us to the point where we can see the result:</p><p><img class="confluence-embedded-image" src="https://cwiki.apache.org/confluence/download/attachments/20645557/error3.png?version=1&modificationDate=1273638562000&api=v2"; data-image-src="/confluence/download/attachments/20645557/error3.png?version=1&modificationDate=1273638562000&api=v2" title="Errors show on Index page"></p><h2 id="OverridingExcep tionReporting-Version3:DecoratingtheRequestExceptionHandler">Version 3: Decorating the RequestExceptionHandler</h2><p>A third option is available: we don't define a <em>new</em> service, but instead <em>decorate</em> the existing RequestExceptionHandler service. This approach means we don't have to make a contribution to the ServiceOverride service.</p><p>Service decoration is a powerful facility of Tapestry that is generally used to "wrap" an existing service with an interceptor that provides new functionality such as logging, security, transaction management or other cross-cutting concerns. The interceptor is an object that implements the same interface as the service being decorated, and usually delegates method invocations to it.</p><p>However, there's no requirement that an interceptor for a service actually invoke methods on the service; here we contribute a new implementation that <em>replaces</em> the original:</p><div class="code panel pdl" style="border-width: 1px;"><div c lass="codeHeader panelHeader pdl" style="border-bottom-width: 1px;"><b>AppModule.java (partial)</b></div><div class="codeContent panelContent pdl"> +<script class="theme: Default; brush: java; gutter: false" type="syntaxhighlighter"><![CDATA[ public RequestExceptionHandler decorateRequestExceptionHandler( final Logger logger, final ResponseRenderer renderer, final ComponentSource componentSource, @@ -339,17 +252,7 @@ public class Index implements ExceptionR }; } ]]></script> -</div></div> - -<p>As with service builder methods and service configuration method, decorator methods are recognized by the "decorate" prefix on the method name. As used here, the rest of the method name is used to identify the service to be decorated (there are other options that allow a decorator to be applied to many different services).</p> - -<p>A change in this version is that when in development mode (that is, when <em>not</em> in production mode) we use the normal implementation. Returning null from a service decoration method indicates that the decorator chooses not to decorate.</p> - -<p>The Logger injected here is the Logger for the service being decorated, the default RequestExceptionHandler service.</p> - -<p>Otherwise, we return an interceptor whose implementation is the same as the new service in version #2.</p> - -<p>The end result is that in development mode we get the full exception report, and in production mode we get an abbreviated message on the application's Index page.</p></div> +</div></div><p>As with service builder methods and service configuration method, decorator methods are recognized by the "decorate" prefix on the method name. As used here, the rest of the method name is used to identify the service to be decorated (there are other options that allow a decorator to be applied to many different services).</p><p>A change in this version is that when in development mode (that is, when <em>not</em> in production mode) we use the normal implementation. Returning null from a service decoration method indicates that the decorator chooses not to decorate.</p><p>The Logger injected here is the Logger for the service being decorated, the default RequestExceptionHandler service.</p><p>Otherwise, we return an interceptor whose implementation is the same as the new service in version #2.</p><p>The end result is that in development mode we get the full exception report, and in production mode we get an abbreviated message on the application's Index page.</p></div > </div> <div class="clearer"></div> Modified: websites/production/tapestry/content/security.html ============================================================================== --- websites/production/tapestry/content/security.html (original) +++ websites/production/tapestry/content/security.html Sat Jan 18 18:21:05 2014 @@ -61,16 +61,14 @@ </div> <div id="content"> -<div id="ConfluenceContent"><p>Tapestry does not come with a built-in security implementation to avoid lock-in to a specific security framework. There are various Java security frameworks available, but the main two Java-based open source security frameworks are Apache Shiro (earlier JSecurity) and Spring Security (earlier Acegi Security). Spring Security is the more popular of the two (because of Spring's popularity), whereas Shiro is widely regarded as the more flexible choice. There are well-maintained Tapestry integration projects for both of these frameworks, <strong><a shape="rect" class="external-link" href="http://tynamo.org/tapestry-security+guide"; >tapestry-security</a></strong> for Apache Shiro (from Tynamo.org) and <strong><a shape="rect" class="external-link" href="http://www.localhost.nu/java/tapestry-spring-security"; >tapestry-spring-security</a></strong> for Spring Security.</p> - -<div class="navmenu" style="float:right; background:#eee; margin:3px; padding:3px"> +<div id="ConfluenceContent"><p>Tapestry does not come with a built-in security implementation to avoid lock-in to a specific security framework. There are various Java security frameworks available, but the main two Java-based open source security frameworks are Apache Shiro (earlier JSecurity) and Spring Security (earlier Acegi Security). Spring Security is the more popular of the two (because of Spring's popularity), whereas Shiro is widely regarded as the more flexible choice. There are well-maintained Tapestry integration projects for both of these frameworks, <strong><a shape="rect" class="external-link" href="http://tynamo.org/tapestry-security+guide"; >tapestry-security</a></strong> for Apache Shiro (from Tynamo.org) and <strong><a shape="rect" class="external-link" href="http://www.localhost.nu/java/tapestry-spring-security"; >tapestry-spring-security</a></strong> for Spring Security.</p><div class="navmenu" style="float:right; background:#eee; margin:3px; padding:3px"> <h3>Related Articles</h3> <ul class="content-by-label"><li> <div> <span class="icon icon-page" title="Page">Page:</span> </div> <div class="details"> - <a shape="rect" href="integrating-with-spring-framework.html">Integrating with Spring Framework</a> + <a shape="rect" href="security.html">Security</a> </div> @@ -79,27 +77,21 @@ <span class="icon icon-page" title="Page">Page:</span> </div> <div class="details"> - <a shape="rect" href="security.html">Security</a> + <a shape="rect" href="https.html">HTTPS</a> </div> - </li></ul> -</div> - -<p>For tapestry-security (Shiro-based)</p> - -<ul><li><a shape="rect" class="external-link" href="http://tynamo.org/tynamo-federatedaccounts+guide"; >Tynamo-federatedaccounts</a> Facebook etc. 3rd party authentication provider integrations, building on Tapestry-security</li></ul> - - -<p>For tapestry-spring-security</p> - -<ul><li><a shape="rect" class="external-link" href="http://www.localhost.nu/java/tapestry-spring-security/conf.html"; >http://www.localhost.nu/java/tapestry-spring-security/conf.html</a></li></ul> - - -<p>To include OpenID with Spring Security in your application, see the following Wiki entry:</p> + </li><li> + <div> + <span class="icon icon-page" title="Page">Page:</span> </div> -<ul><li><a shape="rect" class="external-link" href="http://wiki.apache.org/tapestry/Tapestry5HowToSpringSecurityAndOpenId";>http://wiki.apache.org/tapestry/Tapestry5HowToSpringSecurityAndOpenId</a></li></ul> -</div> + <div class="details"> + <a shape="rect" href="integrating-with-spring-framework.html">Integrating with Spring Framework</a> + + + </div> + </li></ul> +</div><p>For tapestry-security (Shiro-based)</p><ul><li><a shape="rect" class="external-link" href="http://tynamo.org/tynamo-federatedaccounts+guide"; >Tynamo-federatedaccounts</a> Facebook etc. 3rd party authentication provider integrations, building on Tapestry-security</li></ul><p>For tapestry-spring-security</p><ul><li><a shape="rect" class="external-link" href="http://www.localhost.nu/java/tapestry-spring-security/conf.html"; >http://www.localhost.nu/java/tapestry-spring-security/conf.html</a></li></ul><p>To include OpenID with Spring Security in your application, see the following Wiki entry:</p><ul><li><a shape="rect" class="external-link" href="http://wiki.apache.org/tapestry/Tapestry5HowToSpringSecurityAndOpenId";>http://wiki.apache.org/tapestry/Tapestry5HowToSpringSecurityAndOpenId</a></li></ul></div> </div> <div class="clearer"></div> Modified: websites/production/tapestry/content/switching-cases.html ============================================================================== --- websites/production/tapestry/content/switching-cases.html (original) +++ websites/production/tapestry/content/switching-cases.html Sat Jan 18 18:21:05 2014 @@ -29,6 +29,7 @@ <link href='http://cxf.apache.org/resources/highlighter/styles/shThemeCXF.css' rel='stylesheet' type='text/css' /> <script src='http://cxf.apache.org/resources/highlighter/scripts/shCore.js' type='text/javascript'></script> <script src='http://cxf.apache.org/resources/highlighter/scripts/shBrushJava.js' type='text/javascript'></script> + <script src='http://cxf.apache.org/resources/highlighter/scripts/shBrushXml.js' type='text/javascript'></script> <script type="text/javascript"> SyntaxHighlighter.defaults['toolbar'] = false; SyntaxHighlighter.all(); @@ -77,24 +78,10 @@ table.ScrollbarTable td.ScrollbarParent table.ScrollbarTable td.ScrollbarNextName {text-align: right;border: none;} table.ScrollbarTable td.ScrollbarNextIcon {text-align: center;width: 16px;border: none;} -/*]]>*/</style><div class="Scrollbar"><table class="ScrollbarTable"><tr><td colspan="1" rowspan="1" class="ScrollbarPrevIcon"><a shape="rect" href="component-libraries.html"><img align="middle" border="0" src="https://cwiki.apache.org/confluence/images/icons/back_16.gif"; width="16" height="16"></a></td><td colspan="1" rowspan="1" class="ScrollbarPrevName" width="33%"><a shape="rect" href="component-libraries.html">Component Libraries</a> </td><td colspan="1" rowspan="1" class="ScrollbarParent" width="33%"><sup><a shape="rect" href="cookbook.html"><img align="middle" border="0" src="https://cwiki.apache.org/confluence/images/icons/up_16.gif"; width="8" height="8"></a></sup><a shape="rect" href="cookbook.html">Cookbook</a></td><td colspan="1" rowspan="1" class="ScrollbarNextName" width="33%"> <a shape="rect" href="enum-parameter-recipe.html">Enum Parameter Recipe</a></td><td colspan="1" rowspan="1" class="ScrollbarNextIcon"><a shape="rect" href="enum-parameter-recipe.html"><i mg align="middle" border="0" src="https://cwiki.apache.org/confluence/images/icons/forwd_16.gif"; width="16" height="16"></a></td></tr></table></div> -<p></p> - -<h1 id="SwitchingCases-SwitchingCases">Switching Cases</h1> - -<p>With Tapestry's <code>If</code> component you can only test one condition at a time. In order to distinguish multiple cases, you'd have to write complex nested if/else constructs in your page template and have a checker method for each test inside your page class.</p> - -<div class="navmenu" style="float:right; background:#eee; margin:3px; padding:0 1em"> +/*]]>*/</style><div class="Scrollbar"><table class="ScrollbarTable"><tr><td colspan="1" rowspan="1" class="ScrollbarPrevIcon"><a shape="rect" href="component-libraries.html"><img align="middle" border="0" src="https://cwiki.apache.org/confluence/images/icons/back_16.gif"; width="16" height="16"></a></td><td colspan="1" rowspan="1" class="ScrollbarPrevName" width="33%"><a shape="rect" href="component-libraries.html">Component Libraries</a> </td><td colspan="1" rowspan="1" class="ScrollbarParent" width="33%"><sup><a shape="rect" href="cookbook.html"><img align="middle" border="0" src="https://cwiki.apache.org/confluence/images/icons/up_16.gif"; width="8" height="8"></a></sup><a shape="rect" href="cookbook.html">Cookbook</a></td><td colspan="1" rowspan="1" class="ScrollbarNextName" width="33%"> <a shape="rect" href="enum-parameter-recipe.html">Enum Parameter Recipe</a></td><td colspan="1" rowspan="1" class="ScrollbarNextIcon"><a shape="rect" href="enum-parameter-recipe.html"><i mg align="middle" border="0" src="https://cwiki.apache.org/confluence/images/icons/forwd_16.gif"; width="16" height="16"></a></td></tr></table></div><h1 id="SwitchingCases-SwitchingCases">Switching Cases</h1><p>With Tapestry's <code>If</code> component you can only test one condition at a time. In order to distinguish multiple cases, you'd have to write complex nested if/else constructs in your page template and have a checker method for each test inside your page class.</p><div class="navmenu" style="float:right; background:#eee; margin:3px; padding:0 1em"> <p> <strong>JumpStart Demo:</strong><br clear="none"> - <a shape="rect" class="external-link" href="http://jumpstart.doublenegative.com.au/jumpstart/examples/lang/ifnotnegateswitchelseunless"; >If, Not, Negate, Switch, Else, Unless</a></p></div> - -<p>In cases where you have to distinguish multiple cases, the <code>Delegate</code> component comes in. It delegates rendering to some other component, for example a <code>Block</code>. For each case you have, you basically wrap the content inside a <code>Block</code> that doesn't get rendered by default. You then place a Delegate component on your page and point it to a method inside your page class that will decide which of your Blocks should be rendered.</p> - -<p>Imagine for example a use case, where you want to distinguish between 4 cases and you have an int property called <code>whichCase</code> that should be tested against. Your page template would look as follows:</p> - -<div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1px;"><b>SwitchMe.tml</b></div><div class="codeContent panelContent pdl"> -<script class="theme: Default; brush: xml; gutter: false" type="syntaxhighlighter"><![CDATA[ -<html xmlns:t="http://tapestry.apache.org/schema/tapestry_5_1_0.xsd"> + <a shape="rect" class="external-link" href="http://jumpstart.doublenegative.com.au/jumpstart/examples/lang/ifnotnegateswitchelseunless"; >If, Not, Negate, Switch, Else, Unless</a></p></div><p>In cases where you have to distinguish multiple cases, the <code>Delegate</code> component comes in. It delegates rendering to some other component, for example a <code>Block</code>. For each case you have, you basically wrap the content inside a <code>Block</code> that doesn't get rendered by default. You then place a Delegate component on your page and point it to a method inside your page class that will decide which of your Blocks should be rendered.</p><p>Imagine for example a use case, where you want to distinguish between 4 cases and you have an int property called <code>whichCase</code> that should be tested against. Your page template would look as follows:</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1 px;"><b>SwitchMe.tml</b></div><div class="codeContent panelContent pdl"> +<script class="theme: Default; brush: xml; gutter: false" type="syntaxhighlighter"><![CDATA[<html xmlns:t="http://tapestry.apache.org/schema/tapestry_5_1_0.xsd"> <body> <h1>Switch</h1> @@ -118,13 +105,8 @@ table.ScrollbarTable td.ScrollbarNextIco </body> </html> ]]></script> -</div></div> - -<p>You can see, that the <code>Delegate</code> component's <code>to</code> parameter is bound to the case property of your page class. In your page class you therefore have a <code>getCase()</code> method that is responsible for telling the <code>Delegate</code> component which component should be rendered. For that we are injecting references to the <code>Block}}s defined in your page template into the page class and return the according {{Block</code> in the <code>getCase()</code> method.</p> - -<div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1px;"><b>SwitchMe.java</b></div><div class="codeContent panelContent pdl"> -<script class="theme: Default; brush: java; gutter: false" type="syntaxhighlighter"><![CDATA[ -public class SwitchMe +</div></div><p>You can see, that the <code>Delegate</code> component's <code>to</code> parameter is bound to the case property of your page class. In your page class you therefore have a <code>getCase()</code> method that is responsible for telling the <code>Delegate</code> component which component should be rendered. For that we are injecting references to the <code>Block}}s defined in your page template into the page class and return the according {{Block</code> in the <code>getCase()</code> method.</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1px;"><b>SwitchMe.java</b></div><div class="codeContent panelContent pdl"> +<script class="theme: Default; brush: java; gutter: false" type="syntaxhighlighter"><![CDATA[public class SwitchMe { @Persist private int whichCase; @@ -150,9 +132,7 @@ public class SwitchMe } } ]]></script> -</div></div> - -<p>Happy switching!</p></div> +</div></div><p>Happy switching!</p></div> </div> <div class="clearer"></div>
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