rdblue commented on a change in pull request #25104: [SPARK-28341][SQL] create a public API for V2SessionCatalog URL: https://github.com/apache/spark/pull/25104#discussion_r319235220
########## File path: sql/catalyst/src/main/java/org/apache/spark/sql/catalog/v2/CatalogExtension.java ########## @@ -0,0 +1,101 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +package org.apache.spark.sql.catalog.v2; + +import java.util.Map; + +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; +import org.apache.spark.sql.catalyst.analysis.TableAlreadyExistsException; +import org.apache.spark.sql.sources.v2.Table; +import org.apache.spark.sql.types.StructType; +import org.apache.spark.sql.util.CaseInsensitiveStringMap; + +/** + * An API to extend the Spark built-in session catalog. Implementation can override some methods + * to apply custom logic. For example, they can override {@code createTable}, do something else + * before calling {@code super.createTable}. + */ +public abstract class CatalogExtension implements TableCatalog { Review comment: Minor: Using `setDelegateCatalog` requires extending `CatalogExtension`. In Java, I normally try to avoid forcing users to extend a superclass because a class can only have one parent. Instead, I would add `CatalogExtension` as an interface and also create an abstract class, `DelegatingCatalogExtension` that implements the interface. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: [email protected] With regards, Apache Git Services --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
