pudidic commented on code in PR #3444: URL: https://github.com/apache/hive/pull/3444#discussion_r935269108
########## ql/src/java/org/apache/hadoop/hive/ql/parse/repl/dump/DumpExporter.java: ########## @@ -0,0 +1,95 @@ +/* + * 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.hadoop.hive.ql.parse.repl.dump; + +import com.google.common.util.concurrent.ThreadFactoryBuilder; +import org.apache.hadoop.hive.conf.HiveConf; +import org.apache.hadoop.hive.metastore.ThreadPool; +import org.apache.hadoop.hive.ql.metadata.HiveException; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +import java.util.LinkedList; +import java.util.List; +import java.util.concurrent.*; + +public class DumpExporter { Review Comment: The role of DumpExporter isn't to export, which its name implies. It's a wrapper of an ExecutorService, which accepts general Runnable objects with the configured number of threads with a logger. Exposing DumpExporter.submit(Runnable) can lead to unexpected results, especially eating up the thread pool with unexpected tasks and delaying the expected ones. I suggest two design change options; 1. Call private ExecutorService.submit() in a service only. See ScheduledQueryExecutionService and ScheduledQueryExecutor for its pattern. Rename DumpExporter as ExportService and move TableExport and PartitionExport inside ExportService. Hide the object creation from outside and make method call instead. 2. Publish submit(T) and expose interface T for future extension. See JobRequestExecutor and EventualCleanupService for its pattern. Rename DumpExporter as ExportExecutor. Introduce a new interface Export and limit submit(Export) method parameter type. Let TableExport and PartitionExport to implement Export interface. If you can find common methods, you can put them in the Export interface. I prefer the first design as I see there's a small room for future extension. Also please add class description. -- 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. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
