DATACASS-833 - Deprecate cached PreparedStatementCreator support classes.

Since Cassandra driver version 4, the driver itself tracks prepared statements so external prepared statement caching is no longer required.

spring-data-cassandra/src/main/java/org/springframework/data/cassandra/core/cql/CachedPreparedStatementCreator.java

@@ -18,15 +18,16 @@ package org.springframework.data.cassandra.core.cql;
 import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
 
-import com.datastax.oss.driver.api.core.CqlIdentifier;
-import com.datastax.oss.driver.api.core.CqlSession;
-import com.datastax.oss.driver.api.core.DriverException;
-import com.datastax.oss.driver.api.core.cql.PreparedStatement;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 import org.springframework.util.Assert;
 
+import com.datastax.oss.driver.api.core.CqlIdentifier;
+import com.datastax.oss.driver.api.core.CqlSession;
+import com.datastax.oss.driver.api.core.DriverException;
+import com.datastax.oss.driver.api.core.cql.PreparedStatement;
+
 /**
  * This {@link PreparedStatementCreator} maintains a static cache of all prepared statements for the duration of the JVM
  * runtime, more specific the lifecycle of the associated {@link ClassLoader}. When preparing statements with Cassandra,
@@ -38,8 +39,7 @@ import org.springframework.util.Assert;
  * @author David Webb
  * @author Mark Paluch
  * @deprecated since 2.0. This class uses an unsafe, static held cache and is not able to prepare
- *             {@link com.datastax.driver.core.querybuilder.BuiltStatement}. Use
- *             {@link org.springframework.data.cassandra.core.cql.support.CachedPreparedStatementCreator}.
+ *             {@link com.datastax.driver.core.querybuilder.BuiltStatement}.
  */
 @Deprecated
 public class CachedPreparedStatementCreator implements PreparedStatementCreator {

spring-data-cassandra/src/main/java/org/springframework/data/cassandra/core/cql/SimplePreparedStatementCreator.java

@@ -24,14 +24,11 @@ import com.datastax.oss.driver.api.core.cql.SimpleStatement;
 
 /**
  * Trivial implementation of {@link PreparedStatementCreator}. This prepared statement creator simply prepares a
- * statement from the CQL string.
- * <p>
- * This implementation is useful for testing. It should not be used in production systems with high volume reads and
- * writes. Use {@link CachedPreparedStatementCreator} When preparing statements with Cassandra, each Statement should be
- * prepared once and only once due to the overhead of preparing the statement.
+ * statement from the CQL string. Exposes the given CQL statement through {@link CqlProvider#getCql()},
  *
  * @author David Webb
  * @author Mark Paluch
+ * @see CqlProvider
  */
 public class SimplePreparedStatementCreator implements PreparedStatementCreator, CqlProvider {
 

spring-data-cassandra/src/main/java/org/springframework/data/cassandra/core/cql/support/CachedPreparedStatementCreator.java

@@ -15,16 +15,16 @@
  */
 package org.springframework.data.cassandra.core.cql.support;
 
+import org.springframework.data.cassandra.core.cql.PreparedStatementCreator;
+import org.springframework.data.cassandra.core.cql.QueryOptions;
+import org.springframework.util.Assert;
+
 import com.datastax.oss.driver.api.core.CqlSession;
 import com.datastax.oss.driver.api.core.DriverException;
 import com.datastax.oss.driver.api.core.cql.PreparedStatement;
 import com.datastax.oss.driver.api.core.cql.SimpleStatement;
 import com.datastax.oss.driver.api.core.cql.Statement;
 
-import org.springframework.data.cassandra.core.cql.PreparedStatementCreator;
-import org.springframework.data.cassandra.core.cql.QueryOptions;
-import org.springframework.util.Assert;
-
 /**
  * {@link PreparedStatementCreator} implementation using caching of prepared statements.
  * <p />
@@ -35,7 +35,9 @@ import org.springframework.util.Assert;
  * @author Mark Paluch
  * @since 2.0
  * @see PreparedStatementCache
+ * @deprecated since 3.2, the Cassandra driver has a built-in prepared statement cache with makes external caching of prepared statements superfluous.
  */
+@Deprecated
 public class CachedPreparedStatementCreator implements PreparedStatementCreator {
 
 	private final PreparedStatementCache cache;

spring-data-cassandra/src/main/java/org/springframework/data/cassandra/core/cql/support/MapPreparedStatementCache.java

@@ -36,7 +36,9 @@ import com.datastax.oss.driver.api.core.cql.SimpleStatement;
  * @author Mark Paluch
  * @author Aldo Bongio
  * @since 2.0
+ * @deprecated since 3.2, the Cassandra driver has a built-in prepared statement cache with makes external caching of prepared statements superfluous.
  */
+@Deprecated
 public class MapPreparedStatementCache implements PreparedStatementCache {
 
 	private final Map<CacheKey, PreparedStatement> cache;

spring-data-cassandra/src/main/java/org/springframework/data/cassandra/core/cql/support/PreparedStatementCache.java

@@ -31,7 +31,10 @@ import com.datastax.oss.driver.api.core.cql.SimpleStatement;
  * @author Mark Paluch
  * @since 2.0
  * @see PreparedStatement
+ * @deprecated since 3.2, the Cassandra driver has a built-in prepared statement cache with makes external caching of
+ *             prepared statements superfluous.
  */
+@Deprecated
 public interface PreparedStatementCache {
 
 	/**

src/main/asciidoc/reference/reactive-cassandra.adoc

@@ -18,7 +18,7 @@ Spring Data for Apache Cassandra uses consistent naming conventions on objects i
 [[cassandra.reactive.getting-started]]
 == Getting Started
 
-Spring Data for Apache Cassandra requires Apache Cassandra 2.1 or later and Datastax Java Driver 3.0 or later.
+Spring Data for Apache Cassandra requires Apache Cassandra 2.1 or later and Datastax Java Driver 4.0 or later.
 An easy way to quickly set up and bootstrap a working environment is to create a Spring-based project in https://spring.io/tools/sts[STS] or use https://start.spring.io/[Spring Initializer].
 
 First, you need to set up a running Apache Cassandra server.