DATAREDIS-714 - Use Jedis API for database selection.

We now rely more on Jedis to select the appropriate Redis database and we no longer select the database when opening/closing a connection. Previously, we always reset the database if a database index greater zero was configured.
A properly configured Jedis pool ensures that the appropriate database is selected even if the database was selected during connection interaction.

Relying on Jedis reduces the number of issued SELECT commands and improves that way overall performance when executing commands via the Template API.

Original Pull Request: #291

Author: mp911de

src/main/java/org/springframework/data/redis/connection/jedis/JedisConnection.java

@@ -161,7 +161,7 @@ protected JedisConnection(Jedis jedis, @Nullable Pool<Jedis> pool, int dbIndex,
 		// select the db
 		// if this fail, do manual clean-up before propagating the exception
 		// as we're inside the constructor
-		if (dbIndex > 0) {
+		if (dbIndex != jedis.getDB()) {
 			try {
 				select(dbIndex);
 			} catch (DataAccessException ex) {
@@ -332,19 +332,9 @@ public void close() throws DataAccessException {
 			if (broken) {
 				pool.returnBrokenResource(jedis);
 			} else {
-
-				// reset the connection
-				try {
-					if (dbIndex > 0) {
-						jedis.select(0);
-					}
-					return;
-				} catch (Exception ex) {
-					throw convertJedisAccessException(ex);
-				} finally {
-					jedis.close();
-				}
+				jedis.close();
 			}
+			return;
 		}
 		// else close the connection normally (doing the try/catch dance)
 		Exception exc = null;

src/main/java/org/springframework/data/redis/connection/jedis/JedisConnectionFactory.java

@@ -370,7 +370,7 @@ protected Pool<Jedis> createRedisSentinelPool(RedisSentinelConfiguration config)
 
 		GenericObjectPoolConfig poolConfig = getPoolConfig() != null ? getPoolConfig() : new JedisPoolConfig();
 		return new JedisSentinelPool(config.getMaster().getName(), convertToJedisSentinelSet(config.getSentinels()),
-				poolConfig, getConnectTimeout(), getReadTimeout(), getPassword(), Protocol.DEFAULT_DATABASE, getClientName());
+				poolConfig, getConnectTimeout(), getReadTimeout(), getPassword(), getDatabase(), getClientName());
 	}
 
 	/**
@@ -382,7 +382,7 @@ protected Pool<Jedis> createRedisSentinelPool(RedisSentinelConfiguration config)
 	protected Pool<Jedis> createRedisPool() {
 
 		return new JedisPool(getPoolConfig(), getHostName(), getPort(), getConnectTimeout(), getReadTimeout(),
-				getPassword(), Protocol.DEFAULT_DATABASE, getClientName(), isUseSsl(),
+				getPassword(), getDatabase(), getClientName(), isUseSsl(),
 				clientConfiguration.getSslSocketFactory().orElse(null), //
 				clientConfiguration.getSslParameters().orElse(null), //
 				clientConfiguration.getHostnameVerifier().orElse(null));

src/test/java/org/springframework/data/redis/connection/jedis/JedisConnectionIntegrationTests.java

@@ -36,6 +36,7 @@
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.springframework.dao.InvalidDataAccessApiUsageException;
+import org.springframework.data.redis.RedisConnectionFailureException;
 import org.springframework.data.redis.SettingsUtils;
 import org.springframework.data.redis.connection.AbstractConnectionIntegrationTests;
 import org.springframework.data.redis.connection.ConnectionUtils;
@@ -113,13 +114,18 @@ public void testCreateConnectionWithDb() {
 		factory2.destroy();
 	}
 
-	@Test(expected = InvalidDataAccessApiUsageException.class)
+	@Test(expected = RedisConnectionFailureException.class) // DATAREDIS-714
 	public void testCreateConnectionWithDbFailure() {
+
 		JedisConnectionFactory factory2 = new JedisConnectionFactory();
 		factory2.setDatabase(77);
 		factory2.afterPropertiesSet();
-		factory2.getConnection();
-		factory2.destroy();
+
+		try {
+			factory2.getConnection();
+		} finally {
+			factory2.destroy();
+		}
 	}
 
 	@Test
@@ -381,8 +387,8 @@ public void pExpireShouldSupportExiprationForValuesLargerThanInteger() {
 	@RequiresRedisSentinel(SentinelsAvailable.ONE_ACTIVE)
 	public void shouldReturnSentinelCommandsWhenWhenActiveSentinelFound() {
 
-		((JedisConnection) byteConnection).setSentinelConfiguration(new RedisSentinelConfiguration().master("mymaster")
-				.sentinel("127.0.0.1", 26379).sentinel("127.0.0.1", 26380));
+		((JedisConnection) byteConnection).setSentinelConfiguration(
+				new RedisSentinelConfiguration().master("mymaster").sentinel("127.0.0.1", 26379).sentinel("127.0.0.1", 26380));
 		assertThat(connection.getSentinelConnection(), notNullValue());
 	}