DATAREDIS-775 - Polishing.

Remove whitespaces, update Javadoc and use most specific return type to avoid unnecessary casts.

Original Pull Request: #316

src/main/java/org/springframework/data/redis/connection/lettuce/ClusterConnectionProvider.java

@@ -15,7 +15,6 @@
  */
 package org.springframework.data.redis.connection.lettuce;
 
-import io.lettuce.core.AbstractRedisClient;
 import io.lettuce.core.ReadFrom;
 import io.lettuce.core.api.StatefulConnection;
 import io.lettuce.core.cluster.RedisClusterClient;
@@ -97,7 +96,7 @@ class ClusterConnectionProvider implements LettuceConnectionProvider, RedisClien
 	 * @see org.springframework.data.redis.connection.lettuce.RedisClientProvider#getRedisClient()
 	 */
 	@Override
-	public AbstractRedisClient getRedisClient() {
+	public RedisClusterClient getRedisClient() {
 		return client;
 	}
 }

src/main/java/org/springframework/data/redis/connection/lettuce/LettucePoolingConnectionProvider.java

@@ -43,7 +43,7 @@ import org.springframework.util.Assert;
  * @since 2.0
  * @see #getConnection(Class)
  */
-class LettucePoolingConnectionProvider implements LettuceConnectionProvider, RedisClientProvider,  DisposableBean {
+class LettucePoolingConnectionProvider implements LettuceConnectionProvider, RedisClientProvider, DisposableBean {
 
 	private final static Log log = LogFactory.getLog(LettucePoolingConnectionProvider.class);
 

src/main/java/org/springframework/data/redis/connection/lettuce/RedisClientProvider.java

@@ -28,7 +28,7 @@ interface RedisClientProvider {
 	/**
 	 * Returns the underlying Redis Client.
 	 *
-	 * @return the {@link AbstractRedisClient}.
+	 * @return the {@link AbstractRedisClient}. Never {@literal null}.
 	 */
 	AbstractRedisClient getRedisClient();
 }