| /* |
| * 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.gossip.manager; |
| |
| import java.util.List; |
| import java.util.concurrent.TimeUnit; |
| import java.util.concurrent.atomic.AtomicBoolean; |
| |
| import org.apache.gossip.GossipService; |
| import org.apache.gossip.LocalGossipMember; |
| |
| /** |
| * [The active thread: periodically send gossip request.] The class handles gossiping the membership |
| * list. This information is important to maintaining a common state among all the nodes, and is |
| * important for detecting failures. |
| */ |
| abstract public class ActiveGossipThread implements Runnable { |
| |
| protected final GossipManager gossipManager; |
| |
| private final AtomicBoolean keepRunning; |
| |
| public ActiveGossipThread(GossipManager gossipManager) { |
| this.gossipManager = gossipManager; |
| this.keepRunning = new AtomicBoolean(true); |
| } |
| |
| @Override |
| public void run() { |
| while (keepRunning.get()) { |
| try { |
| TimeUnit.MILLISECONDS.sleep(gossipManager.getSettings().getGossipInterval()); |
| sendMembershipList(gossipManager.getMyself(), gossipManager.getMemberList()); |
| } catch (InterruptedException e) { |
| GossipService.LOGGER.error(e); |
| keepRunning.set(false); |
| } |
| } |
| shutdown(); |
| } |
| |
| public void shutdown() { |
| keepRunning.set(false); |
| } |
| |
| /** |
| * Performs the sending of the membership list, after we have incremented our own heartbeat. |
| */ |
| abstract protected void sendMembershipList(LocalGossipMember me, |
| List<LocalGossipMember> memberList); |
| |
| /** |
| * Abstract method which should be implemented by a subclass. This method should return a member |
| * of the list to gossip with. |
| * |
| * @param memberList |
| * The list of members which are stored in the local list of members. |
| * @return The chosen LocalGossipMember to gossip with. |
| */ |
| abstract protected LocalGossipMember selectPartner(List<LocalGossipMember> memberList); |
| } |