| /** |
| * 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.pulsar.common.naming; |
| |
| import java.util.ArrayList; |
| import java.util.Collections; |
| import java.util.List; |
| import java.util.concurrent.CompletableFuture; |
| import org.apache.pulsar.broker.namespace.NamespaceService; |
| |
| /** |
| * This algorithm divides the bundle into two parts with the same topics count. |
| */ |
| public class TopicCountEquallyDivideBundleSplitAlgorithm implements NamespaceBundleSplitAlgorithm { |
| |
| @Override |
| public CompletableFuture<Long> getSplitBoundary(NamespaceService service, NamespaceBundle bundle) { |
| return service.getOwnedTopicListForNamespaceBundle(bundle).thenCompose(topics -> { |
| if (topics == null || topics.size() <= 1) { |
| return CompletableFuture.completedFuture(null); |
| } |
| List<Long> topicNameHashList = new ArrayList<>(topics.size()); |
| for (String topic : topics) { |
| topicNameHashList.add(bundle.getNamespaceBundleFactory().getLongHashCode(topic)); |
| } |
| Collections.sort(topicNameHashList); |
| long splitStart = topicNameHashList.get(Math.max((topicNameHashList.size() / 2) - 1, 0)); |
| long splitEnd = topicNameHashList.get(topicNameHashList.size() / 2); |
| long splitMiddle = splitStart + (splitEnd - splitStart) / 2; |
| return CompletableFuture.completedFuture(splitMiddle); |
| }); |
| } |
| } |