Fix update to cache documentation. (#1359)

Closes #1358.

src/main/asciidoc/caching.adoc

@@ -0,0 +1,57 @@
+[[couchbase.caching]]
+= Caching
+
+This chapter describes additional support for caching and `@Cacheable`.
+
+[[caching.usage]]
+== Configuration & Usage
+
+Technically, caching is not part of spring-data, but is implemented directly in the spring core. Most database implementations in the spring-data package can't support `@Cacheable`, because it is not possible to store arbitrary data.
+
+Couchbase supports both binary and JSON data, so you can get both out of the same database.
+
+To make it work, you need to add the `@EnableCaching` annotation and configure the `cacheManager` bean:
+
+.`AbstractCouchbaseConfiguration` for Caching
+====
+[source,java]
+----
+
+@Configuration
+@EnableCaching
+public class Config extends AbstractCouchbaseConfiguration {
+    // general methods
+
+    @Bean
+    public CouchbaseCacheManager cacheManager(CouchbaseTemplate couchbaseTemplate) throws Exception {
+        CouchbaseCacheManager.CouchbaseCacheManagerBuilder builder = CouchbaseCacheManager.CouchbaseCacheManagerBuilder
+                .fromConnectionFactory(couchbaseTemplate.getCouchbaseClientFactory());
+            return builder.build();
+        }
+
+----
+====
+
+The `persistent` identifier can then be used on the `@Cacheable` annotation to identify the cache manager to use (you can have more than one configured).
+
+Once it is set up, you can annotate every method with the `@Cacheable` annotation to transparently cache it in your couchbase bucket. You can also customize how the key is generated.
+
+.Caching example
+====
+[source,java]
+----
+@Cacheable(value="persistent", key="'longrunsim-'+#time")
+public String simulateLongRun(long time) {
+    try {
+        Thread.sleep(time);
+    } catch(Exception ex) {
+        System.out.println("This shouldnt happen...");
+    }
+    return "I've slept " + time + " miliseconds.;
+}
+----
+====
+
+If you run the method multiple times, you'll see a set operation happening first, followed by multiple get operations and no sleep time (which fakes the expensive execution). You can store whatever you want, if it is JSON of course you can access it through views and look at it in the Web UI.
+
+Note that to use cache.clear() or catch.invalidate(), the bucket must have a primary key.

src/test/java/org/springframework/data/couchbase/domain/Config.java

@@ -17,12 +17,17 @@
 package org.springframework.data.couchbase.domain;
 
 import java.lang.reflect.InvocationTargetException;
+import java.util.HashMap;
+import java.util.Map;
 
+import org.springframework.cache.annotation.EnableCaching;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.data.auditing.DateTimeProvider;
 import org.springframework.data.couchbase.CouchbaseClientFactory;
 import org.springframework.data.couchbase.SimpleCouchbaseClientFactory;
+import org.springframework.data.couchbase.cache.CouchbaseCacheConfiguration;
+import org.springframework.data.couchbase.cache.CouchbaseCacheManager;
 import org.springframework.data.couchbase.config.AbstractCouchbaseConfiguration;
 import org.springframework.data.couchbase.core.CouchbaseTemplate;
 import org.springframework.data.couchbase.core.ReactiveCouchbaseTemplate;
@@ -214,6 +219,13 @@ public class Config extends AbstractCouchbaseConfiguration {
 		return jacksonTranslationService;
 	}
 
+	@Bean
+	public CouchbaseCacheManager cacheManager(CouchbaseTemplate couchbaseTemplate) throws Exception {
+		CouchbaseCacheManager.CouchbaseCacheManagerBuilder builder = CouchbaseCacheManager.CouchbaseCacheManagerBuilder
+				.fromConnectionFactory(couchbaseTemplate.getCouchbaseClientFactory());
+		return builder.build();
+	}
+
 	@Override
 	public String typeKey() {
 		return "t"; // this will override '_class', is passed in to new CustomMappingCouchbaseConverter