| /* |
| * 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.cassandra.dht; |
| |
| import java.util.HashSet; |
| import java.util.Set; |
| |
| import org.apache.cassandra.config.DatabaseDescriptor; |
| import org.apache.cassandra.locator.IEndpointSnitch; |
| import org.apache.cassandra.locator.InetAddressAndPort; |
| import org.apache.cassandra.service.StorageService; |
| |
| public class Datacenters |
| { |
| |
| private static class DCHandle |
| { |
| private static final String thisDc = DatabaseDescriptor.getEndpointSnitch().getLocalDatacenter(); |
| } |
| |
| public static String thisDatacenter() |
| { |
| return DCHandle.thisDc; |
| } |
| |
| /* |
| * (non-javadoc) Method to generate list of valid data center names to be used to validate the replication parameters during CREATE / ALTER keyspace operations. |
| * All peers of current node are fetched from {@link TokenMetadata} and then a set is build by fetching DC name of each peer. |
| * @return a set of valid DC names |
| */ |
| public static Set<String> getValidDatacenters() |
| { |
| final Set<String> validDataCenters = new HashSet<>(); |
| final IEndpointSnitch snitch = DatabaseDescriptor.getEndpointSnitch(); |
| |
| // Add data center of localhost. |
| validDataCenters.add(thisDatacenter()); |
| // Fetch and add DCs of all peers. |
| for (InetAddressAndPort peer : StorageService.instance.getTokenMetadata().getAllEndpoints()) |
| { |
| validDataCenters.add(snitch.getDatacenter(peer)); |
| } |
| |
| return validDataCenters; |
| } |
| } |