Document how to enable Hibernate 2nd level cache with JCache

Closes gh-14734

spring-boot-project/spring-boot-docs/pom.xml

@@ -577,6 +577,11 @@
 			<artifactId>hibernate-core</artifactId>
 			<optional>true</optional>
 		</dependency>
+		<dependency>
+			<groupId>org.hibernate</groupId>
+			<artifactId>hibernate-jcache</artifactId>
+			<optional>true</optional>
+		</dependency>
 		<dependency>
 			<groupId>org.hibernate.validator</groupId>
 			<artifactId>hibernate-validator</artifactId>

spring-boot-project/spring-boot-docs/src/main/asciidoc/howto.adoc

@@ -2003,6 +2003,27 @@ for more details.
 
 
 
+[[howto-configure-hibernate-second-level-caching]]
+=== Configure Hibernate Second-Level Caching
+Hibernate {hibernate-documentation}#caching[second-level cache] can be configured for a
+range of cache providers. Rather than configuring Hibernate to lookup the cache provider
+again, it is better to provide the one that is available in the context whenever possible.
+
+If you're using JCache, this is pretty easy. First, make sure that
+`org.hibernate:hibernate-jcache` is available on the classpath. Then, add a
+`HibernatePropertiesCustomizer` bean as shown in the following example:
+
+[source,java,indent=0]
+----
+include::{code-examples}/jpa/HibernateSecondLevelCacheExample.java[tag=configuration]
+----
+
+This customizer will configure Hibernate to use the same `CacheManager` as the one that
+the application uses. It is also possible to use separate `CacheManager` instances, refer
+to {hibernate-documentation}#caching-provider-jcache[the Hibernate user guide].
+
+
+
 [[howto-use-dependency-injection-hibernate-components]]
 === Use Dependency Injection in Hibernate Components
 By default, Spring Boot registers a `BeanContainer` implementation that uses the

spring-boot-project/spring-boot-docs/src/main/java/org/springframework/boot/docs/jpa/HibernateSecondLevelCacheExample.java

+/*
+ * Copyright 2012-2018 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
+ *
+ *      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.springframework.boot.docs.jpa;
+
+import org.hibernate.cache.jcache.ConfigSettings;
+
+import org.springframework.boot.autoconfigure.orm.jpa.HibernatePropertiesCustomizer;
+import org.springframework.cache.jcache.JCacheCacheManager;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+
+/**
+ * Example configuration of using JCache and Hibernate to enable second level caching.
+ *
+ * @author Stephane Nicoll
+ */
+// tag::configuration[]
+@Configuration
+public class HibernateSecondLevelCacheExample {
+
+	@Bean
+	public HibernatePropertiesCustomizer hibernateSecondLevelCacheCustomizer(
+			JCacheCacheManager cacheManager) {
+		return (properties) -> properties.put(ConfigSettings.CACHE_MANAGER,
+				cacheManager.getCacheManager());
+
+	}
+
+}
+// end::configuration[]