Polishing.

Delegate RedisClientProvider.getClient() across connection providers. Use SimpleAsyncTaskExecutor as default in ClusterCommandExecutor to avoid ThreadPoolTaskExecutor pollution.

See #2575

src/main/java/org/springframework/data/redis/connection/ClusterCommandExecutor.java

@@ -24,6 +24,7 @@ import java.util.stream.Collectors;
 
 import org.springframework.beans.factory.DisposableBean;
 import org.springframework.core.task.AsyncTaskExecutor;
+import org.springframework.core.task.SimpleAsyncTaskExecutor;
 import org.springframework.dao.DataAccessException;
 import org.springframework.data.redis.ClusterRedirectException;
 import org.springframework.data.redis.ClusterStateFailureException;
@@ -87,9 +88,7 @@ public class ClusterCommandExecutor implements DisposableBean {
 
 	{
 		if (executor == null) {
-			ThreadPoolTaskExecutor threadPoolTaskExecutor = new ThreadPoolTaskExecutor();
-			threadPoolTaskExecutor.initialize();
-			this.executor = threadPoolTaskExecutor;
+			this.executor = new SimpleAsyncTaskExecutor();
 		}
 	}
 

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

@@ -99,7 +99,6 @@ class LettucePoolingConnectionProvider implements LettuceConnectionProvider, Red
 			StatefulConnection<?, ?> connection = pool.borrowObject();
 
 			poolRef.put(connection, pool);
-
 			return connectionType.cast(connection);
 		} catch (Exception e) {
 			throw new PoolException("Could not get a resource from the pool", e);

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

@@ -15,6 +15,7 @@
  */
 package org.springframework.data.redis.connection.lettuce;
 
+import io.lettuce.core.AbstractRedisClient;
 import io.lettuce.core.ReadFrom;
 import io.lettuce.core.RedisClient;
 import io.lettuce.core.RedisURI;
@@ -44,7 +45,7 @@ import org.springframework.lang.Nullable;
  * @author Christoph Strobl
  * @since 2.0
  */
-class StandaloneConnectionProvider implements LettuceConnectionProvider, TargetAware {
+class StandaloneConnectionProvider implements LettuceConnectionProvider, TargetAware, RedisClientProvider {
 
 	private final RedisClient client;
 	private final RedisCodec<?, ?> codec;
@@ -142,6 +143,11 @@ class StandaloneConnectionProvider implements LettuceConnectionProvider, TargetA
 				.failed(new UnsupportedOperationException("Connection type " + connectionType + " not supported"));
 	}
 
+	@Override
+	public AbstractRedisClient getRedisClient() {
+		return client;
+	}
+
 	private StatefulRedisConnection masterReplicaConnection(RedisURI redisUri, ReadFrom readFrom) {
 
 		StatefulRedisMasterReplicaConnection<?, ?> connection = MasterReplica.connect(client, codec, redisUri);