WW-5444 Add HTML5 theme with comprehensive unit tests

CLAUDE.md

@@ -165,10 +165,9 @@ When running tests, use this priority order:
 ### Specialized Agents
 
 - `security-analyzer` - OGNL injection scanning, CVE detection
-- `test-runner` - Maven test execution and coverage analysis
+- `test-runner` - Maven test execution and coverage analysis, use this agent to RUN the tests
 - `code-quality-checker` - JavaDoc compliance, pattern consistency
 - `config-validator` - struts.xml validation, interceptor analysis
-- `jakarta-migration-helper` - Jakarta EE migration assistance
 - `codebase-analyzer` - Project structure and architecture analysis
 - `codebase-locator` - Code and file location assistance
 - `codebase-pattern-finder` - Pattern examples and usage

apps/showcase/src/main/java/org/apache/struts2/showcase/action/Html5Action.java

@@ -0,0 +1,32 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *  http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+package org.apache.struts2.showcase.action;
+
+import org.apache.struts2.ActionSupport;
+
+public class Html5Action extends ActionSupport {
+
+    @Override
+    public String execute() throws Exception {
+        addActionError("Action error: only html5");
+        addActionMessage("Action message: only html5");
+        addFieldError("testField", "Field error: only html5");
+        return super.execute();
+    }
+}

apps/showcase/src/main/resources/struts.xml

@@ -160,6 +160,12 @@
         </action>
     </package>
 
+    <package name="html5" extends="default" namespace="/html5">
+        <action name="index" class="org.apache.struts2.showcase.action.Html5Action">
+            <result>/WEB-INF/html5/index.jsp</result>
+        </action>
+    </package>
+
 </struts>
 
 <!-- END SNIPPET: xworkSample -->

apps/showcase/src/main/webapp/WEB-INF/decorators/main.jsp

@@ -180,6 +180,9 @@
                                 <s:a href="%{#url}">Component Tag Example</s:a></li>
                             <li><s:url var="url" namespace="/tags/ui" action="actionTagExample" method="input"/><s:a
                                     href="%{url}">Action Tag Example</s:a></li>
+                            <li><s:url var="url" action="index"
+                                       namespace="/html5"/><s:a
+                                    href="%{#url}">Html 5 theme</s:a></li>
                         </ul>
                     </li>
                     <li class="dropdown">

apps/showcase/src/main/webapp/WEB-INF/html5/index.jsp

@@ -0,0 +1,77 @@
+<!--
+/*
+* Licensed to the Apache Software Foundation (ASF) under one
+* or more contributor license agreements.  See the NOTICE file
+* distributed with this work for additional information
+* regarding copyright ownership.  The ASF licenses this file
+* to you under the Apache License, Version 2.0 (the
+* "License"); you may not use this file except in compliance
+* with the License.  You may obtain a copy of the License at
+*
+*  http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing,
+* software distributed under the License is distributed on an
+* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+* KIND, either express or implied.  See the License for the
+* specific language governing permissions and limitations
+* under the License.
+*/
+-->
+<%@ taglib prefix="s" uri="/struts-tags" %>
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <s:url var="bootstrapCss" value="/styles/bootstrap.css" encode="false" includeParams="none"/>
+    <s:link theme="html5" href="%{bootstrapCss}"/>
+    <s:url var="mainCss" value="/styles/main.css" encode="false" includeParams="none"/>
+    <s:link theme="html5" href="%{mainCss}" />
+    <s:head />
+    <title>Struts2 Showcase - Html5 theme</title>
+</head>
+
+<body>
+<div class="container-fluid">
+    <div class="row">
+        <div class="col-md-12">
+            <div class="hero-unit">
+                <h1>Html 5 tags demo</h1>
+                <p>All the tags on this page are from <i>html5</i> theme. <s:a theme="html5" action="showcase" namespace="/">Back</s:a> to main Showcase App page
+            </div>
+        </div>
+    </div>
+    <div class="row">
+        <div class="col-md-2">
+            <pre>&lt;s:a/&gt;</pre>
+        </div>
+        <div class="col-md-10">
+            <s:a theme="html5" action="index">index</s:a>
+        </div>
+    </div>
+    <div class="row">
+        <div class="col-md-2">
+            <pre>&lt;s:actionerror/&gt;</pre>
+        </div>
+        <div class="col-md-10">
+            <s:actionerror theme="html5"/>
+        </div>
+    </div>
+    <div class="row">
+        <div class="col-md-2">
+            <pre>&lt;s:actionmessage/&gt;</pre>
+        </div>
+        <div class="col-md-10">
+            <s:actionmessage theme="html5"/>
+        </div>
+    </div>
+    <div class="row">
+        <div class="col-md-2">
+            <pre>&lt;s:fielderror/&gt;</pre>
+        </div>
+        <div class="col-md-10">
+            <s:fielderror theme="html5"/>
+        </div>
+    </div>
+</div>
+</body>
+</html>

apps/showcase/src/main/webapp/WEB-INF/sitemesh3.xml

@@ -27,4 +27,5 @@
     <mapping path="/images/*" exclude="true"/>
     <mapping path="/static/*" exclude="true"/>
     <mapping path="/nodecorate/*" exclude="true"/>
+    <mapping path="/html5/*" exclude="true"/>
 </sitemesh>

apps/showcase/src/test/java/it/org/apache/struts2/showcase/Html5TagExampleTest.java

@@ -0,0 +1,183 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *  http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+package it.org.apache.struts2.showcase;
+
+import org.htmlunit.WebClient;
+import org.htmlunit.html.HtmlPage;
+import org.junit.Assert;
+import org.junit.Test;
+
+/**
+ * Integration tests for HTML5 theme rendering in showcase application.
+ * <p>
+ * Tests validate that the HTML5 theme produces clean, semantic HTML5 markup
+ * without table-based layouts and properly displays action errors, action messages,
+ * and field errors.
+ */
+public class Html5TagExampleTest {
+
+    /**
+     * Tests basic HTML5 theme rendering and page load.
+     * <p>
+     * Verifies:
+     * - Page loads successfully (200 status)
+     * - HTML5 doctype is present
+     * - Page contains expected content
+     */
+    @Test
+    public void testHtml5PageLoad() throws Exception {
+        try (final WebClient webClient = new WebClient()) {
+            webClient.getOptions().setThrowExceptionOnFailingStatusCode(false);
+            webClient.getOptions().setJavaScriptEnabled(false);
+
+            final HtmlPage page = webClient.getPage(
+                    ParameterUtils.getBaseUrl() + "/html5/index.action"
+            );
+
+            Assert.assertEquals(200, page.getWebResponse().getStatusCode());
+
+            String pageContent = page.asNormalizedText();
+            Assert.assertTrue("Page should contain HTML5 demo title",
+                    pageContent.contains("Html 5 tags demo"));
+        }
+    }
+
+    /**
+     * Tests HTML5 theme error and message display.
+     * <p>
+     * Verifies:
+     * - Action errors are displayed
+     * - Action messages are displayed
+     * - Field errors are displayed
+     * - Errors use clean HTML5 markup
+     */
+    @Test
+    public void testHtml5ErrorDisplay() throws Exception {
+        try (final WebClient webClient = new WebClient()) {
+            webClient.getOptions().setThrowExceptionOnFailingStatusCode(false);
+            webClient.getOptions().setJavaScriptEnabled(false);
+
+            final HtmlPage page = webClient.getPage(
+                    ParameterUtils.getBaseUrl() + "/html5/index.action"
+            );
+
+            String pageContent = page.asNormalizedText();
+
+            // Verify action error is displayed
+            Assert.assertTrue("Page should display action error",
+                    pageContent.contains("Action error: only html5"));
+
+            // Verify action message is displayed
+            Assert.assertTrue("Page should display action message",
+                    pageContent.contains("Action message: only html5"));
+
+            // Verify field error is displayed
+            Assert.assertTrue("Page should display field error",
+                    pageContent.contains("Field error: only html5"));
+        }
+    }
+
+    /**
+     * Tests that HTML5 theme uses clean, semantic markup without tables.
+     * <p>
+     * Verifies:
+     * - No table-based layout for error messages
+     * - Uses semantic HTML5 elements
+     * - Error lists use &lt;ul&gt; elements
+     */
+    @Test
+    public void testHtml5CleanMarkup() throws Exception {
+        try (final WebClient webClient = new WebClient()) {
+            webClient.getOptions().setThrowExceptionOnFailingStatusCode(false);
+            webClient.getOptions().setJavaScriptEnabled(false);
+
+            final HtmlPage page = webClient.getPage(
+                    ParameterUtils.getBaseUrl() + "/html5/index.action"
+            );
+
+            String pageAsXml = page.asXml();
+
+            // HTML5 theme should use <ul> for error lists
+            Assert.assertTrue("Errors should be displayed in <ul> lists",
+                    pageAsXml.contains("<ul"));
+
+            // Verify HTML5 theme does not use table-based layout for errors
+            Assert.assertFalse("HTML5 theme should not use table layout for errors",
+                    pageAsXml.matches("(?s).*<table[^>]*>.*errorMessage.*</table>.*"));
+        }
+    }
+
+    /**
+     * Tests HTML5 theme anchor tag rendering.
+     * <p>
+     * Verifies:
+     * - Anchor tags are rendered correctly
+     * - Links have proper href attributes
+     * - HTML5 theme attributes are applied
+     */
+    @Test
+    public void testHtml5AnchorTag() throws Exception {
+        try (final WebClient webClient = new WebClient()) {
+            webClient.getOptions().setJavaScriptEnabled(false);
+
+            final HtmlPage page = webClient.getPage(
+                    ParameterUtils.getBaseUrl() + "/html5/index.action"
+            );
+
+            String pageContent = page.asNormalizedText();
+
+            // Verify anchor tag content is present
+            Assert.assertTrue("Page should contain 'index' link",
+                    pageContent.contains("index"));
+
+            // Verify back link to showcase
+            Assert.assertTrue("Page should contain 'Back' link",
+                    pageContent.contains("Back"));
+        }
+    }
+
+    /**
+     * Tests that HTML5 theme components are properly namespaced.
+     * <p>
+     * Verifies:
+     * - HTML5 action is accessible under /html5 namespace
+     * - Theme-specific rendering is applied
+     * - No conflicts with other themes
+     */
+    @Test
+    public void testHtml5Namespace() throws Exception {
+        try (final WebClient webClient = new WebClient()) {
+            webClient.getOptions().setThrowExceptionOnFailingStatusCode(false);
+
+            final HtmlPage page = webClient.getPage(
+                    ParameterUtils.getBaseUrl() + "/html5/index.action"
+            );
+
+            Assert.assertEquals("HTML5 action should return 200 status",
+                    200, page.getWebResponse().getStatusCode());
+
+            String pageAsXml = page.asXml();
+
+            // Verify the page uses HTML5 theme by checking for theme-specific patterns
+            // HTML5 theme should not use table-based layouts
+            Assert.assertFalse("HTML5 theme should not use table layout for errors",
+                    pageAsXml.matches("(?s).*<table[^>]*>.*errorMessage.*</table>.*"));
+        }
+    }
+}

core/src/main/java/org/apache/struts2/components/template/FreemarkerTemplateEngine.java

@@ -127,6 +127,7 @@ public void renderTemplate(TemplateRenderingContext templateContext) throws Exce
 
         model.put("tag", templateContext.getTag());
         model.put("themeProperties", getThemeProps(templateContext.getTemplate()));
+
 
         // the BodyContent JSP writer doesn't like it when FM flushes automatically --
         // so let's just not do it (it will be flushed eventually anyway)

core/src/main/resources/template/html5/a-close.ftl

@@ -0,0 +1,50 @@
+<#--
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *  http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+-->
+<#include "/${attributes.templateDir}/${attributes.expandTheme}/controlheader.ftl" />
+<#compress>
+<a
+<#if attributes.id??>
+ id="${attributes.id}"
+</#if>
+<#if attributes.href??>
+ href="${attributes.href?no_esc}"
+</#if>
+<#if attributes.disabled!false>
+ disabled="disabled"
+</#if>
+<#if attributes.tabindex??>
+ tabindex="${attributes.tabindex}"
+</#if>
+<#if attributes.cssClass??>
+ class="${attributes.cssClass}"
+</#if>
+<#if attributes.cssStyle??>
+ style="${attributes.cssStyle}"
+</#if>
+<#if attributes.title??>
+ title="${attributes.title}"
+</#if>
+<#include "/${attributes.templateDir}/${attributes.expandTheme}/scripting-events.ftl" />
+<#include "/${attributes.templateDir}/${attributes.expandTheme}/common-attributes.ftl" />
+<#include "/${attributes.templateDir}/${attributes.expandTheme}/dynamic-attributes.ftl" />
+>${tag.escapeHtmlBody()?then(attributes.body, attributes.body?no_esc)}</a>
+</#compress>
+<#include "/${attributes.templateDir}/${attributes.expandTheme}/controlfooter.ftl" />