Add support for Redis SINTERCARD command

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

@@ -82,6 +82,7 @@
  * @author Dennis Neufeld
  * @author Shyngys Sapraliyev
  * @author Jeonggyu Choi
+ * @author Mingi Lee
  */
 @NullUnmarked
 @SuppressWarnings({ "ConstantConditions", "deprecation" })
@@ -832,6 +833,11 @@ public Long sInterStore(byte[] destKey, byte[]... keys) {
 		return convertAndReturn(delegate.sInterStore(destKey, keys), Converters.identityConverter());
 	}
 
+	@Override
+	public Long sInterCard(byte[]... keys) {
+		return convertAndReturn(delegate.sInterCard(keys), Converters.identityConverter());
+	}
+
 	@Override
 	public Boolean sIsMember(byte[] key, byte[] value) {
 		return convertAndReturn(delegate.sIsMember(key, value), Converters.identityConverter());
@@ -1824,6 +1830,11 @@ public Long sInterStore(String destKey, String... keys) {
 		return sInterStore(serialize(destKey), serializeMulti(keys));
 	}
 
+	@Override
+	public Long sInterCard(String... keys) {
+		return sInterCard(serializeMulti(keys));
+	}
+
 	@Override
 	public Boolean sIsMember(String key, String value) {
 		return sIsMember(serialize(key), serialize(value));

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

@@ -67,6 +67,7 @@
  * @author Dennis Neufeld
  * @author Shyngys Sapraliyev
  * @author Tihomir Mateev
+ * @author Mingi Lee
  * @since 2.0
  */
 @Deprecated
@@ -890,6 +891,13 @@ default Long sInterStore(byte[] destKey, byte[]... keys) {
 		return setCommands().sInterStore(destKey, keys);
 	}
 
+	/** @deprecated in favor of {@link RedisConnection#setCommands()}}. */
+	@Override
+	@Deprecated
+	default Long sInterCard(byte[]... keys) {
+		return setCommands().sInterCard(keys);
+	}
+
 	/** @deprecated in favor of {@link RedisConnection#setCommands()}}. */
 	@Override
 	@Deprecated

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

@@ -29,6 +29,7 @@
  * @author Costin Leau
  * @author Christoph Strobl
  * @author Mark Paluch
+ * @author Mingi Lee
  * @see RedisCommands
  */
 @NullUnmarked
@@ -153,6 +154,16 @@ public interface RedisSetCommands {
 	 */
 	Long sInterStore(byte @NonNull [] destKey, byte @NonNull [] @NonNull... keys);
 
+	/**
+	 * Returns the cardinality of the set which would result from the intersection of all the given sets.
+	 *
+	 * @param keys must not be {@literal null}.
+	 * @return {@literal null} when used in pipeline / transaction.
+	 * @see <a href="https://redis.io/commands/sintercard">Redis Documentation: SINTERCARD</a>
+	 * @since 3.4
+	 */
+	Long sInterCard(byte @NonNull [] @NonNull... keys);
+
 	/**
 	 * Union all sets at given {@code keys}.
 	 *

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

@@ -74,6 +74,7 @@
  * @author ihaohong
  * @author Shyngys Sapraliyev
  * @author Jeonggyu Choi
+ * @author Mingi Lee
  * @see RedisCallback
  * @see RedisSerializer
  * @see StringRedisTemplate
@@ -1169,6 +1170,17 @@ String bLMove(@NonNull String sourceKey, @NonNull String destinationKey, @NonNul
 	 */
 	Long sInterStore(@NonNull String destKey, @NonNull String @NonNull... keys);
 
+	/**
+	 * Returns the cardinality of the set which would result from the intersection of all the given sets.
+	 *
+	 * @param keys must not be {@literal null}.
+	 * @return
+	 * @see <a href="https://redis.io/commands/sintercard">Redis Documentation: SINTERCARD</a>
+	 * @see RedisSetCommands#sInterCard(byte[]...)
+	 * @since 3.4
+	 */
+	Long sInterCard(@NonNull String @NonNull... keys);
+
 	/**
 	 * Union all sets at given {@code keys}.
 	 *

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

@@ -40,6 +40,7 @@
 /**
  * @author Christoph Strobl
  * @author Mark Paluch
+ * @author Mingi Lee
  * @since 2.0
  */
 class JedisClusterSetCommands implements RedisSetCommands {
@@ -230,6 +231,25 @@ public Long sInterStore(byte[] destKey, byte[]... keys) {
 		return sAdd(destKey, result.toArray(new byte[result.size()][]));
 	}
 
+	@Override
+	public Long sInterCard(byte[]... keys) {
+
+		Assert.notNull(keys, "Keys must not be null");
+		Assert.noNullElements(keys, "Keys must not contain null elements");
+
+		if (ClusterSlotHashUtil.isSameSlotForAllKeys(keys)) {
+			try {
+				return connection.getCluster().sintercard(keys);
+			} catch (Exception ex) {
+				throw convertJedisAccessException(ex);
+			}
+		}
+
+		// For multi-slot clusters, calculate intersection cardinality by performing intersection
+		Set<byte[]> result = sInter(keys);
+		return (long) result.size();
+	}
+
 	@Override
 	public Set<byte[]> sUnion(byte[]... keys) {
 

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

@@ -38,6 +38,7 @@
 /**
  * @author Christoph Strobl
  * @author Mark Paluch
+ * @author Mingi Lee
  * @since 2.0
  */
 @NullUnmarked
@@ -105,6 +106,15 @@ public Long sInterStore(byte @NonNull [] destKey, byte @NonNull [] @NonNull... k
 		return connection.invoke().just(Jedis::sinterstore, PipelineBinaryCommands::sinterstore, destKey, keys);
 	}
 
+	@Override
+	public Long sInterCard(byte @NonNull [] @NonNull... keys) {
+
+		Assert.notNull(keys, "Keys must not be null");
+		Assert.noNullElements(keys, "Keys must not contain null elements");
+
+		return connection.invoke().just(Jedis::sintercard, PipelineBinaryCommands::sintercard, keys);
+	}
+
 	@Override
 	public Boolean sIsMember(byte @NonNull [] key, byte @NonNull [] value) {
 

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

@@ -31,6 +31,7 @@
 /**
  * @author Christoph Strobl
  * @author Mark Paluch
+ * @author Mingi Lee
  * @since 2.0
  */
 class LettuceClusterSetCommands extends LettuceSetCommands {
@@ -118,6 +119,21 @@ public Long sInterStore(byte[] destKey, byte[]... keys) {
 		return sAdd(destKey, result.toArray(new byte[result.size()][]));
 	}
 
+	@Override
+	public Long sInterCard(byte[]... keys) {
+
+		Assert.notNull(keys, "Keys must not be null");
+		Assert.noNullElements(keys, "Keys must not contain null elements");
+
+		if (ClusterSlotHashUtil.isSameSlotForAllKeys(keys)) {
+			return super.sInterCard(keys);
+		}
+
+		// For multi-slot clusters, calculate intersection cardinality by performing intersection
+		Set<byte[]> result = sInter(keys);
+		return (long) result.size();
+	}
+
 	@Override
 	public Set<byte[]> sUnion(byte[]... keys) {
 

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

@@ -39,6 +39,7 @@
 /**
  * @author Christoph Strobl
  * @author Mark Paluch
+ * @author Mingi Lee
  * @since 2.0
  */
 @NullUnmarked
@@ -106,6 +107,15 @@ public Long sInterStore(byte @NonNull [] destKey, byte @NonNull [] @NonNull... k
 		return connection.invoke().just(RedisSetAsyncCommands::sinterstore, destKey, keys);
 	}
 
+	@Override
+	public Long sInterCard(byte @NonNull [] @NonNull... keys) {
+
+		Assert.notNull(keys, "Keys must not be null");
+		Assert.noNullElements(keys, "Keys must not contain null elements");
+
+		return connection.invoke().just(RedisSetAsyncCommands::sintercard, keys);
+	}
+
 	@Override
 	public Boolean sIsMember(byte @NonNull [] key, byte @NonNull [] value) {
 

src/main/java/org/springframework/data/redis/core/DefaultSetOperations.java

@@ -140,6 +140,25 @@ public Long intersectAndStore(Collection<K> keys, K destKey) {
 		return execute(connection -> connection.sInterStore(rawDestKey, rawKeys));
 	}
 
+	@Override
+	public Long intersectSize(K key, K otherKey) {
+		return intersectSize(Arrays.asList(key, otherKey));
+	}
+
+	@Override
+	public Long intersectSize(K key, Collection<K> otherKeys) {
+
+		byte[][] rawKeys = rawKeys(key, otherKeys);
+		return execute(connection -> connection.sInterCard(rawKeys));
+	}
+
+	@Override
+	public Long intersectSize(Collection<K> keys) {
+
+		byte[][] rawKeys = rawKeys(keys);
+		return execute(connection -> connection.sInterCard(rawKeys));
+	}
+
 	@Override
 	public Boolean isMember(K key, Object o) {
 

src/main/java/org/springframework/data/redis/core/SetOperations.java

@@ -30,6 +30,7 @@
  * @author Christoph Strobl
  * @author Mark Paluch
  * @author Roman Bezpalko
+ * @author Mingi Lee
  */
 @NullUnmarked
 public interface SetOperations<K, V> {
@@ -178,6 +179,38 @@ public interface SetOperations<K, V> {
 	 */
 	Long intersectAndStore(@NonNull Collection<@NonNull K> keys, @NonNull K destKey);
 
+	/**
+	 * Returns the cardinality of the set which would result from the intersection of {@code key} and {@code otherKey}.
+	 *
+	 * @param key must not be {@literal null}.
+	 * @param otherKey must not be {@literal null}.
+	 * @return {@literal null} when used in pipeline / transaction.
+	 * @see <a href="https://redis.io/commands/sintercard">Redis Documentation: SINTERCARD</a>
+	 * @since 3.4
+	 */
+	Long intersectSize(@NonNull K key, @NonNull K otherKey);
+
+	/**
+	 * Returns the cardinality of the set which would result from the intersection of {@code key} and {@code otherKeys}.
+	 *
+	 * @param key must not be {@literal null}.
+	 * @param otherKeys must not be {@literal null}.
+	 * @return {@literal null} when used in pipeline / transaction.
+	 * @see <a href="https://redis.io/commands/sintercard">Redis Documentation: SINTERCARD</a>
+	 * @since 3.4
+	 */
+	Long intersectSize(@NonNull K key, @NonNull Collection<@NonNull K> otherKeys);
+
+	/**
+	 * Returns the cardinality of the set which would result from the intersection of all given sets at {@code keys}.
+	 *
+	 * @param keys must not be {@literal null}.
+	 * @return {@literal null} when used in pipeline / transaction.
+	 * @see <a href="https://redis.io/commands/sintercard">Redis Documentation: SINTERCARD</a>
+	 * @since 3.4
+	 */
+	Long intersectSize(@NonNull Collection<@NonNull K> keys);
+
 	/**
 	 * Union all sets at given {@code keys} and {@code otherKey}.
 	 *

src/test/java/org/springframework/data/redis/core/DefaultSetOperationsIntegrationTests.java

@@ -38,6 +38,7 @@
  * @author Christoph Strobl
  * @author Thomas Darimont
  * @author Mark Paluch
+ * @author Mingi Lee
  */
 @ParameterizedClass
 @MethodSource("testParams")
@@ -329,6 +330,38 @@ void intersectAndStoreShouldReturnNumberOfElementsInDestination() {
 		assertThat(setOps.intersectAndStore(Arrays.asList(sourceKey1, sourceKey2), destinationKey)).isEqualTo(2L);
 	}
 
+	@Test // GH-2906
+	@EnabledOnCommand("SINTERCARD")
+	void intersectSizeShouldReturnIntersectionCardinality() {
+
+		K sourceKey1 = keyFactory.instance();
+		K sourceKey2 = keyFactory.instance();
+		K sourceKey3 = keyFactory.instance();
+
+		V v1 = valueFactory.instance();
+		V v2 = valueFactory.instance();
+		V v3 = valueFactory.instance();
+		V v4 = valueFactory.instance();
+		V v5 = valueFactory.instance();
+
+		setOps.add(sourceKey1, v1, v2, v3);
+		setOps.add(sourceKey2, v2, v3, v4);
+		setOps.add(sourceKey3, v3, v4, v5);
+
+		// Test two keys intersection
+		assertThat(setOps.intersectSize(sourceKey1, sourceKey2)).isEqualTo(2L);
+
+		// Test key and collection intersection
+		assertThat(setOps.intersectSize(sourceKey1, Arrays.asList(sourceKey2, sourceKey3))).isEqualTo(1L);
+
+		// Test collection intersection
+		assertThat(setOps.intersectSize(Arrays.asList(sourceKey1, sourceKey2, sourceKey3))).isEqualTo(1L);
+
+		// Test empty intersection
+		K emptyKey = keyFactory.instance();
+		assertThat(setOps.intersectSize(sourceKey1, emptyKey)).isEqualTo(0L);
+	}
+
 	@Test // GH-2037
 	@EnabledOnCommand("SMISMEMBER")
 	void isMember() {