jectpro7 commented on code in PR #24681: URL: https://github.com/apache/flink/pull/24681#discussion_r1574275399
########## flink-state-backends/flink-statebackend-forst/src/main/java/org/apache/flink/state/forst/ForStGeneralMultiGetOperation.java: ########## @@ -0,0 +1,105 @@ +/* + * 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.flink.state.forst; + +import org.rocksdb.RocksDB; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +import java.io.IOException; +import java.util.Arrays; +import java.util.List; +import java.util.concurrent.CompletableFuture; +import java.util.concurrent.Executor; +import java.util.concurrent.atomic.AtomicInteger; + +/** + * The general-purpose multiGet operation implementation for ForStDB, which simulates multiGet by + * calling the Get API multiple times with multiple threads. + * + * @param <K> The type of key in get access request. + * @param <V> The type of value in get access request. + */ +public class ForStGeneralMultiGetOperation<K, V> implements ForStDBOperation<List<V>> { + + private static final Logger LOG = LoggerFactory.getLogger(ForStGeneralMultiGetOperation.class); + + private final RocksDB db; + + private final List<Request<K, V>> batchRequest; + + private final Executor executor; + + ForStGeneralMultiGetOperation(RocksDB db, List<Request<K, V>> batchRequest, Executor executor) { + this.db = db; + this.batchRequest = batchRequest; + this.executor = executor; + } + + @Override + public CompletableFuture<List<V>> process() throws IOException { + + CompletableFuture<List<V>> future = new CompletableFuture<>(); + @SuppressWarnings("unchecked") + V[] result = (V[]) new Object[batchRequest.size()]; + Arrays.fill(result, null); + + AtomicInteger counter = new AtomicInteger(batchRequest.size()); + for (int i = 0; i < batchRequest.size(); i++) { + Request<K, V> request = batchRequest.get(i); + final int index = i; + executor.execute( + () -> { + try { + ForStInnerTable<K, V> table = request.table; + byte[] key = table.serializeKey(request.key); + byte[] value = db.get(table.getColumnFamilyHandle(), key); Review Comment: oh, got it, good to learn. Thanks for sharing the background. -- 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: issues-unsubscr...@flink.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
