Add Lettuce Redis driver autoconfiguration

Introduce an alternative autoconfiguration if the lettuce Redis driver is
available. Add Lettuce-specific configuration property options
"spring.redis.lettuce.shutdown-timeout" to control the shutdown timeout
of the lettuce driver. Add documentation for the properties, the
supported drivers, and how to switch between drivers.

Split client-specific properties from spring.redis.pool to
spring.redis.jedis.pool and introduce spring.redis.lettuce namespace.
Deprecate spring.redis.pool property.

See gh-5311

spring-boot-docs/src/main/asciidoc/appendix-application-properties.adoc

@@ -852,21 +852,36 @@ content into your application; rather pick only the properties that you need.
 	spring.redis.host=localhost # Redis server host.
 	spring.redis.password= # Login password of the redis server.
 	spring.redis.ssl=false # Enable SSL support.
-	spring.redis.pool.max-active=8 # Max number of connections that can be allocated by the pool at a given time. Use a negative value for no limit.
-	spring.redis.pool.max-idle=8 # Max number of "idle" connections in the pool. Use a negative value to indicate an unlimited number of idle connections.
-	spring.redis.pool.max-wait=-1 # Maximum amount of time (in milliseconds) a connection allocation should block before throwing an exception when the pool is exhausted. Use a negative value to block indefinitely.
-	spring.redis.pool.min-idle=0 # Target for the minimum number of idle connections to maintain in the pool. This setting only has an effect if it is positive.
+	spring.redis.jedis.pool.max-active=8 # Max number of connections that can be allocated by the pool at a given time. Use a negative value for no limit.
+	spring.redis.jedis.pool.max-idle=8 # Max number of "idle" connections in the pool. Use a negative value to indicate an unlimited number of idle connections.
+	spring.redis.jedis.pool.max-wait=-1 # Maximum amount of time (in milliseconds) a connection allocation should block before throwing an exception when the pool is exhausted. Use a negative value to block indefinitely.
+	spring.redis.jedis.pool.min-idle=0 # Target for the minimum number of idle connections to maintain in the pool. This setting only has an effect if it is positive.
 	spring.redis.port=6379 # Redis server port.
 	spring.redis.sentinel.master= # Name of Redis server.
 	spring.redis.sentinel.nodes= # Comma-separated list of host:port pairs.
 	spring.redis.timeout=0 # Connection timeout in milliseconds.
+	spring.redis.ssl.enabled=false # Enable SSL support.
+	spring.redis.ssl.verify-peer=true # Enable SSL peer verification.
+	spring.redis.ssl.start-tls=false # Enable StartTLS support.
+
+	# REDIS JEDIS DRIVER
+	spring.redis.jedis.pool.max-active=8 # Max number of connections that can be allocated by the pool at a given time. Use a negative value for no limit.
+	spring.redis.jedis.pool.max-idle=8 # Max number of "idle" connections in the pool. Use a negative value to indicate an unlimited number of idle connections.
+	spring.redis.jedis.pool.max-wait=-1 # Maximum amount of time (in milliseconds) a connection allocation should block before throwing an exception when the pool is exhausted. Use a negative value to block indefinitely.
+	spring.redis.jedis.pool.min-idle=0 # Target for the minimum number of idle connections to maintain in the pool. This setting only has an effect if it is positive.
+
+	# REDIS LETTUCE DRIVER
+	spring.redis.lettuce.pool.max-active=8 # Max number of connections that can be allocated by the pool at a given time. Use a negative value for no limit.
+	spring.redis.lettuce.pool.max-idle=8 # Max number of "idle" connections in the pool. Use a negative value to indicate an unlimited number of idle connections.
+	spring.redis.lettuce.pool.max-wait=-1 # Maximum amount of time (in milliseconds) a connection allocation should block before throwing an exception when the pool is exhausted. Use a negative value to block indefinitely.
+	spring.redis.lettuce.pool.min-idle=0 # Target for the minimum number of idle connections to maintain in the pool. This setting only has an effect if it is positive.
+	spring.redis.lettuce.shutdown-timeout=2000 # Shutdown timeout in milliseconds.
+
 
 	# TRANSACTION ({sc-spring-boot-autoconfigure}/transaction/TransactionProperties.{sc-ext}[TransactionProperties])
 	spring.transaction.default-timeout= # Default transaction timeout in seconds.
 	spring.transaction.rollback-on-commit-failure= # Perform the rollback on commit failures.
 
-
-
 	# ----------------------------------------
 	# INTEGRATION PROPERTIES
 	# ----------------------------------------

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

@@ -3074,3 +3074,44 @@ but the rest of it is normal for a Spring application in Servlet 2.5. Example:
 In this example we are using a single application context (the one created by the context
 listener) and attaching it to the `DispatcherServlet` using an init parameter. This is
 normal in a Spring Boot application (you normally only have one application context).
+
+[[howto-use-lettuce-instead-of-jedis]]
+=== Use Lettuce instead of Jedis
+The Spring Boot Redis starter (`spring-boot-starter-data-redis` in particular) uses
+https://github.com/xetorthio/jedis/[Jedis] by default. You need to exclude that dependency
+and include the https://github.com/lettuce-io/lettuce-core/[Lettuce] one instead. Spring Boot provides a managed dependency
+to help make this process as easy as possible.
+
+Example in Maven:
+
+[source,xml,indent=0,subs="verbatim,quotes,attributes"]
+----
+	<dependency>
+		<groupId>org.springframework.boot</groupId>
+		<artifactId>spring-boot-starter-data-redis</artifactId>
+		<exclusions>
+			<exclusion>
+				<groupId>redis.clients</groupId>
+				<artifactId>jedis</artifactId>
+			</exclusion>
+		</exclusions>
+	</dependency>
+	<dependency>
+		<groupId>io.lettuce</groupId>
+		<artifactId>lettuce-core</artifactId>
+	</dependency>
+----
+
+Example in Gradle:
+
+[source,groovy,indent=0,subs="verbatim,quotes,attributes"]
+----
+	configurations {
+		compile.exclude module: "jedis"
+	}
+
+	dependencies {
+		compile("io.lettuce:lettuce-core:{lettuce.version}")
+		// ...
+	}
+----

spring-boot-docs/src/main/asciidoc/spring-boot-features.adoc

@@ -3262,10 +3262,11 @@ http://projects.spring.io/spring-data[projects.spring.io/spring-data].
 === Redis
 http://redis.io/[Redis] is a cache, message broker and richly-featured key-value store.
 Spring Boot offers basic auto-configuration for the
-https://github.com/xetorthio/jedis/[Jedis] client library and abstractions on top of it
-provided by https://github.com/spring-projects/spring-data-redis[Spring Data Redis]. There
+https://github.com/xetorthio/jedis/[Jedis] and and https://github.com/mp911de/lettuce/[Lettuce]
+client library and abstractions on top of it provided by
+https://github.com/spring-projects/spring-data-redis[Spring Data Redis]. There
 is a `spring-boot-starter-data-redis` '`Starter`' for collecting the dependencies in a
-convenient way.
+convenient way that uses https://github.com/xetorthio/jedis/[Jedis] by default.