Remove web concerns from template package and move out of -all

Co-authored-by: Phillip Webb <phil.webb@broadcom.com>

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/template/PathBasedTemplateAvailabilityProvider.java

@@ -0,0 +1,104 @@
+/*
+ * Copyright 2012-2025 the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.springframework.boot.autoconfigure.template;
+
+import java.util.List;
+
+import org.springframework.boot.context.properties.bind.Binder;
+import org.springframework.core.env.Environment;
+import org.springframework.core.io.ResourceLoader;
+import org.springframework.util.ClassUtils;
+
+/**
+ * Abstract base class for {@link TemplateAvailabilityProvider} implementations that find
+ * templates from paths.
+ *
+ * @author Andy Wilkinson
+ * @author Phillip Webb
+ * @author Madhura Bhave
+ * @since 1.4.6
+ */
+public abstract class PathBasedTemplateAvailabilityProvider implements TemplateAvailabilityProvider {
+
+	private final String className;
+
+	private final Class<TemplateAvailabilityProperties> propertiesClass;
+
+	private final String propertyPrefix;
+
+	@SuppressWarnings("unchecked")
+	public PathBasedTemplateAvailabilityProvider(String className,
+			Class<? extends TemplateAvailabilityProperties> propertiesClass, String propertyPrefix) {
+		this.className = className;
+		this.propertiesClass = (Class<TemplateAvailabilityProperties>) propertiesClass;
+		this.propertyPrefix = propertyPrefix;
+	}
+
+	@Override
+	public boolean isTemplateAvailable(String view, Environment environment, ClassLoader classLoader,
+			ResourceLoader resourceLoader) {
+		if (ClassUtils.isPresent(this.className, classLoader)) {
+			Binder binder = Binder.get(environment);
+			TemplateAvailabilityProperties properties = binder.bindOrCreate(this.propertyPrefix, this.propertiesClass);
+			return isTemplateAvailable(view, resourceLoader, properties);
+		}
+		return false;
+	}
+
+	private boolean isTemplateAvailable(String view, ResourceLoader resourceLoader,
+			TemplateAvailabilityProperties properties) {
+		String location = properties.getPrefix() + view + properties.getSuffix();
+		for (String path : properties.getLoaderPath()) {
+			if (resourceLoader.getResource(path + location).exists()) {
+				return true;
+			}
+		}
+		return false;
+	}
+
+	protected abstract static class TemplateAvailabilityProperties {
+
+		private String prefix;
+
+		private String suffix;
+
+		protected TemplateAvailabilityProperties(String prefix, String suffix) {
+			this.prefix = prefix;
+			this.suffix = suffix;
+		}
+
+		protected abstract List<String> getLoaderPath();
+
+		public String getPrefix() {
+			return this.prefix;
+		}
+
+		public void setPrefix(String prefix) {
+			this.prefix = prefix;
+		}
+
+		public String getSuffix() {
+			return this.suffix;
+		}
+
+		public void setSuffix(String suffix) {
+			this.suffix = suffix;
+		}
+
+	}
+
+}

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/template/TemplateAvailabilityProvider.java

@@ -0,0 +1,43 @@
+/*
+ * Copyright 2012-2025 the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.springframework.boot.autoconfigure.template;
+
+import org.springframework.core.env.Environment;
+import org.springframework.core.io.ResourceLoader;
+
+/**
+ * Indicates the availability of view templates for a particular templating engine such as
+ * FreeMarker or Thymeleaf.
+ *
+ * @author Andy Wilkinson
+ * @since 1.1.0
+ */
+@FunctionalInterface
+public interface TemplateAvailabilityProvider {
+
+	/**
+	 * Returns {@code true} if a template is available for the given {@code view}.
+	 * @param view the view name
+	 * @param environment the environment
+	 * @param classLoader the class loader
+	 * @param resourceLoader the resource loader
+	 * @return if the template is available
+	 */
+	boolean isTemplateAvailable(String view, Environment environment, ClassLoader classLoader,
+			ResourceLoader resourceLoader);
+
+}

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/template/TemplateAvailabilityProviders.java

@@ -0,0 +1,166 @@
+/*
+ * Copyright 2012-2025 the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.springframework.boot.autoconfigure.template;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.LinkedHashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
+
+import org.springframework.context.ApplicationContext;
+import org.springframework.core.env.Environment;
+import org.springframework.core.io.ResourceLoader;
+import org.springframework.core.io.support.SpringFactoriesLoader;
+import org.springframework.util.Assert;
+
+/**
+ * Collection of {@link TemplateAvailabilityProvider} beans that can be used to check
+ * which (if any) templating engine supports a given view. Caches responses unless the
+ * {@code spring.template.provider.cache} property is set to {@code false}.
+ *
+ * @author Phillip Webb
+ * @author Madhura Bhave
+ * @since 1.4.0
+ */
+public class TemplateAvailabilityProviders {
+
+	private final List<TemplateAvailabilityProvider> providers;
+
+	private static final int CACHE_LIMIT = 1024;
+
+	private static final TemplateAvailabilityProvider NONE = new NoTemplateAvailabilityProvider();
+
+	/**
+	 * Resolved template views, returning already cached instances without a global lock.
+	 */
+	private final Map<String, TemplateAvailabilityProvider> resolved = new ConcurrentHashMap<>(CACHE_LIMIT);
+
+	/**
+	 * Map from view name resolve template view, synchronized when accessed.
+	 */
+	private final Map<String, TemplateAvailabilityProvider> cache = new LinkedHashMap<>(CACHE_LIMIT, 0.75f, true) {
+
+		@Override
+		protected boolean removeEldestEntry(Map.Entry<String, TemplateAvailabilityProvider> eldest) {
+			if (size() > CACHE_LIMIT) {
+				TemplateAvailabilityProviders.this.resolved.remove(eldest.getKey());
+				return true;
+			}
+			return false;
+		}
+
+	};
+
+	/**
+	 * Create a new {@link TemplateAvailabilityProviders} instance.
+	 * @param applicationContext the source application context
+	 */
+	public TemplateAvailabilityProviders(ApplicationContext applicationContext) {
+		this((applicationContext != null) ? applicationContext.getClassLoader() : null);
+	}
+
+	/**
+	 * Create a new {@link TemplateAvailabilityProviders} instance.
+	 * @param classLoader the source class loader
+	 */
+	public TemplateAvailabilityProviders(ClassLoader classLoader) {
+		Assert.notNull(classLoader, "'classLoader' must not be null");
+		this.providers = SpringFactoriesLoader.loadFactories(TemplateAvailabilityProvider.class, classLoader);
+	}
+
+	/**
+	 * Create a new {@link TemplateAvailabilityProviders} instance.
+	 * @param providers the underlying providers
+	 */
+	protected TemplateAvailabilityProviders(Collection<? extends TemplateAvailabilityProvider> providers) {
+		Assert.notNull(providers, "'providers' must not be null");
+		this.providers = new ArrayList<>(providers);
+	}
+
+	/**
+	 * Return the underlying providers being used.
+	 * @return the providers being used
+	 */
+	public List<TemplateAvailabilityProvider> getProviders() {
+		return this.providers;
+	}
+
+	/**
+	 * Get the provider that can be used to render the given view.
+	 * @param view the view to render
+	 * @param applicationContext the application context
+	 * @return a {@link TemplateAvailabilityProvider} or null
+	 */
+	public TemplateAvailabilityProvider getProvider(String view, ApplicationContext applicationContext) {
+		Assert.notNull(applicationContext, "'applicationContext' must not be null");
+		return getProvider(view, applicationContext.getEnvironment(), applicationContext.getClassLoader(),
+				applicationContext);
+	}
+
+	/**
+	 * Get the provider that can be used to render the given view.
+	 * @param view the view to render
+	 * @param environment the environment
+	 * @param classLoader the class loader
+	 * @param resourceLoader the resource loader
+	 * @return a {@link TemplateAvailabilityProvider} or null
+	 */
+	public TemplateAvailabilityProvider getProvider(String view, Environment environment, ClassLoader classLoader,
+			ResourceLoader resourceLoader) {
+		Assert.notNull(view, "'view' must not be null");
+		Assert.notNull(environment, "'environment' must not be null");
+		Assert.notNull(classLoader, "'classLoader' must not be null");
+		Assert.notNull(resourceLoader, "'resourceLoader' must not be null");
+		Boolean useCache = environment.getProperty("spring.template.provider.cache", Boolean.class, true);
+		if (!useCache) {
+			return findProvider(view, environment, classLoader, resourceLoader);
+		}
+		TemplateAvailabilityProvider provider = this.resolved.get(view);
+		if (provider == null) {
+			synchronized (this.cache) {
+				provider = findProvider(view, environment, classLoader, resourceLoader);
+				provider = (provider != null) ? provider : NONE;
+				this.resolved.put(view, provider);
+				this.cache.put(view, provider);
+			}
+		}
+		return (provider != NONE) ? provider : null;
+	}
+
+	private TemplateAvailabilityProvider findProvider(String view, Environment environment, ClassLoader classLoader,
+			ResourceLoader resourceLoader) {
+		for (TemplateAvailabilityProvider candidate : this.providers) {
+			if (candidate.isTemplateAvailable(view, environment, classLoader, resourceLoader)) {
+				return candidate;
+			}
+		}
+		return null;
+	}
+
+	private static final class NoTemplateAvailabilityProvider implements TemplateAvailabilityProvider {
+
+		@Override
+		public boolean isTemplateAvailable(String view, Environment environment, ClassLoader classLoader,
+				ResourceLoader resourceLoader) {
+			return false;
+		}
+
+	}
+
+}

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/template/TemplateLocation.java

@@ -0,0 +1,82 @@
+/*
+ * Copyright 2012-2025 the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.springframework.boot.autoconfigure.template;
+
+import java.io.IOException;
+
+import org.springframework.core.io.Resource;
+import org.springframework.core.io.ResourceLoader;
+import org.springframework.core.io.support.ResourcePatternResolver;
+import org.springframework.util.Assert;
+
+/**
+ * Contains a location that templates can be loaded from.
+ *
+ * @author Phillip Webb
+ * @since 1.2.1
+ */
+public class TemplateLocation {
+
+	private final String path;
+
+	public TemplateLocation(String path) {
+		Assert.notNull(path, "'path' must not be null");
+		this.path = path;
+	}
+
+	/**
+	 * Determine if this template location exists using the specified
+	 * {@link ResourcePatternResolver}.
+	 * @param resolver the resolver used to test if the location exists
+	 * @return {@code true} if the location exists.
+	 */
+	public boolean exists(ResourcePatternResolver resolver) {
+		Assert.notNull(resolver, "'resolver' must not be null");
+		if (resolver.getResource(this.path).exists()) {
+			return true;
+		}
+		try {
+			return anyExists(resolver);
+		}
+		catch (IOException ex) {
+			return false;
+		}
+	}
+
+	private boolean anyExists(ResourcePatternResolver resolver) throws IOException {
+		String searchPath = this.path;
+		if (searchPath.startsWith(ResourceLoader.CLASSPATH_URL_PREFIX)) {
+			searchPath = ResourcePatternResolver.CLASSPATH_ALL_URL_PREFIX
+					+ searchPath.substring(ResourceLoader.CLASSPATH_URL_PREFIX.length());
+		}
+		if (searchPath.startsWith(ResourcePatternResolver.CLASSPATH_ALL_URL_PREFIX)) {
+			Resource[] resources = resolver.getResources(searchPath);
+			for (Resource resource : resources) {
+				if (resource.exists()) {
+					return true;
+				}
+			}
+		}
+		return false;
+	}
+
+	@Override
+	public String toString() {
+		return this.path;
+	}
+
+}

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/template/TemplateRuntimeHints.java

@@ -0,0 +1,34 @@
+/*
+ * Copyright 2012-2025 the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.springframework.boot.autoconfigure.template;
+
+import org.springframework.aot.hint.RuntimeHints;
+import org.springframework.aot.hint.RuntimeHintsRegistrar;
+
+/**
+ * {@link RuntimeHintsRegistrar} for default template location.
+ *
+ * @author Stephane Nicoll
+ */
+class TemplateRuntimeHints implements RuntimeHintsRegistrar {
+
+	@Override
+	public void registerHints(RuntimeHints hints, ClassLoader classLoader) {
+		hints.resources().registerPatternIfPresent(classLoader, "templates", (hint) -> hint.includes("templates/**"));
+	}
+
+}

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/template/package-info.java

@@ -0,0 +1,20 @@
+/*
+ * Copyright 2012-2025 the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.
+ */
+
+/**
+ * Base classes for template Auto-configuration.
+ */
+package org.springframework.boot.autoconfigure.template;

spring-boot-project/spring-boot-autoconfigure/src/main/resources/META-INF/spring/aot.factories

@@ -3,3 +3,6 @@ org.springframework.boot.autoconfigure.logging.ConditionEvaluationReportLoggingP
 
 org.springframework.beans.factory.aot.BeanRegistrationExcludeFilter=\
 org.springframework.boot.autoconfigure.SharedMetadataReaderFactoryContextInitializer
+
+org.springframework.aot.hint.RuntimeHintsRegistrar=\
+org.springframework.boot.autoconfigure.template.TemplateRuntimeHints