| /** |
| * 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.storm.testing; |
| |
| import java.util.HashMap; |
| import java.util.List; |
| import java.util.Map; |
| import java.util.TreeSet; |
| import java.util.concurrent.ConcurrentHashMap; |
| import org.apache.storm.networktopography.AbstractDNSToSwitchMapping; |
| import org.apache.storm.networktopography.DNSToSwitchMapping; |
| |
| /** |
| * This class implements the {@link DNSToSwitchMapping} interface It alternates bewteen RACK1 and RACK2 for the hosts. |
| */ |
| @SuppressWarnings("checkstyle:AbbreviationAsWordInName") |
| public final class AlternateRackDNSToSwitchMapping extends AbstractDNSToSwitchMapping { |
| |
| private Map<String, String> mappingCache = new ConcurrentHashMap<String, String>(); |
| |
| @Override |
| public Map<String, String> resolve(List<String> names) { |
| TreeSet<String> sortedNames = new TreeSet<String>(names); |
| Map<String, String> m = new HashMap<String, String>(); |
| if (names.isEmpty()) { |
| //name list is empty, return an empty map |
| return m; |
| } |
| |
| Boolean odd = true; |
| for (String name : sortedNames) { |
| if (odd) { |
| m.put(name, "RACK1"); |
| mappingCache.put(name, "RACK1"); |
| odd = false; |
| } else { |
| m.put(name, "RACK2"); |
| mappingCache.put(name, "RACK2"); |
| odd = true; |
| } |
| } |
| return m; |
| } |
| |
| @Override |
| public String toString() { |
| return "defaultRackDNSToSwitchMapping (" + mappingCache.size() + " mappings cached)"; |
| } |
| } |