Polish contribution

Closes gh-4903

spring-boot-samples/spring-boot-sample-cache/README.adoc

@@ -84,6 +84,13 @@ a redis instance with the default settings is expected on your local box).
 
 
 
+=== Caffeine
+Simply add the `com.github.ben-manes.caffeine:caffeine` dependency to enable support
+for Caffeine. You can customize how caches are created in different ways, see
+`application.properties` for an example and the documentation for more details.
+
+
+
 === Guava
 Spring Boot does not provide any dependency management for _Guava_ so you'll have to add
 the `com.google.guava:guava` dependency with a version. You can customize how caches are

spring-boot-samples/spring-boot-sample-cache/src/main/resources/application.properties

@@ -10,6 +10,12 @@
 #spring.cache.jcache.config=hazelcast.xml
 
 
+#
+# Caffeine configuration
+#
+#spring.cache.caffeine.spec=maximumSize=200,expireAfterAccess=600s
+
+
 #
 # Guava configuration
 #