| /* |
| * 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.locator; |
| |
| import java.net.InetAddress; |
| import java.util.*; |
| |
| import org.apache.cassandra.config.DatabaseDescriptor; |
| |
| public abstract class AbstractEndpointSnitch implements IEndpointSnitch |
| { |
| public abstract int compareEndpoints(InetAddress target, InetAddress a1, InetAddress a2); |
| |
| /** |
| * Sorts the <tt>Collection</tt> of node addresses by proximity to the given address |
| * @param address the address to sort by proximity to |
| * @param unsortedAddress the nodes to sort |
| * @return a new sorted <tt>List</tt> |
| */ |
| public List<InetAddress> getSortedListByProximity(InetAddress address, Collection<InetAddress> unsortedAddress) |
| { |
| List<InetAddress> preferred = new ArrayList<InetAddress>(unsortedAddress); |
| sortByProximity(address, preferred); |
| return preferred; |
| } |
| |
| /** |
| * Sorts the <tt>List</tt> of node addresses, in-place, by proximity to the given address |
| * @param address the address to sort the proximity by |
| * @param addresses the nodes to sort |
| */ |
| public void sortByProximity(final InetAddress address, List<InetAddress> addresses) |
| { |
| Collections.sort(addresses, new Comparator<InetAddress>() |
| { |
| public int compare(InetAddress a1, InetAddress a2) |
| { |
| return compareEndpoints(address, a1, a2); |
| } |
| }); |
| } |
| |
| public void gossiperStarting() |
| { |
| // noop by default |
| } |
| |
| public boolean isWorthMergingForRangeQuery(List<InetAddress> merged, List<InetAddress> l1, List<InetAddress> l2) |
| { |
| // Querying remote DC is likely to be an order of magnitude slower than |
| // querying locally, so 2 queries to local nodes is likely to still be |
| // faster than 1 query involving remote ones |
| boolean mergedHasRemote = hasRemoteNode(merged); |
| return mergedHasRemote |
| ? hasRemoteNode(l1) || hasRemoteNode(l2) |
| : true; |
| } |
| |
| private boolean hasRemoteNode(List<InetAddress> l) |
| { |
| String localDc = DatabaseDescriptor.getLocalDataCenter(); |
| for (InetAddress ep : l) |
| { |
| if (!localDc.equals(getDatacenter(ep))) |
| return true; |
| } |
| return false; |
| } |
| } |