add Experimental

Author: cloud-fan

sql/catalyst/src/main/java/org/apache/spark/sql/catalog/v2/CatalogExtension.java

@@ -17,6 +17,7 @@
 
 package org.apache.spark.sql.catalog.v2;
 
+import org.apache.spark.annotation.Experimental;
 import org.apache.spark.sql.util.CaseInsensitiveStringMap;
 
 /**
@@ -26,6 +27,7 @@
  * implement {@code createTable}, do something else before calling {@code createTable} of the
  * built-in session catalog.
  */
+@Experimental
 public interface CatalogExtension extends TableCatalog {
 
   /**

sql/catalyst/src/main/java/org/apache/spark/sql/catalog/v2/DelegatingCatalogExtension.java

@@ -19,6 +19,7 @@
 
 import java.util.Map;
 
+import org.apache.spark.annotation.Experimental;
 import org.apache.spark.sql.catalog.v2.expressions.Transform;
 import org.apache.spark.sql.catalyst.analysis.NoSuchNamespaceException;
 import org.apache.spark.sql.catalyst.analysis.NoSuchTableException;
@@ -33,6 +34,7 @@
  * only need to override some methods where they want to apply custom logic. For example, they can
  * override {@code createTable}, do something else before calling {@code super.createTable}.
  */
+@Experimental
 public abstract class DelegatingCatalogExtension implements CatalogExtension {
 
   private TableCatalog delegate;