| /* |
| * 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.geode.distributed.internal; |
| |
| import java.util.List; |
| import java.util.Set; |
| |
| import org.apache.geode.distributed.internal.membership.InternalDistributedMember; |
| |
| /** |
| * This interface specifies callback methods that are invoked when remote GemFire systems enter and |
| * exit the distributed cache. Note that a {@code MembershipListener} can be added from any VM, |
| * but the callback methods are always invoked in the GemFire manager VM. Thus, the callback methods |
| * should not perform time-consuming operations. |
| * |
| * @see ClusterDistributionManager#addMembershipListener |
| */ |
| public interface MembershipListener { |
| |
| /** |
| * This method is invoked when a new member joins the system |
| * |
| * @param distributionManager that is calling this listener |
| * @param id The id of the new member that has joined the system |
| */ |
| default void memberJoined(DistributionManager distributionManager, InternalDistributedMember id) { |
| // implement if needed |
| } |
| |
| /** |
| * This method is invoked after a member has explicitly left the system. It may not get invoked if |
| * a member becomes unreachable due to crash or network problems. |
| * |
| * @param distributionManager that is calling this listener |
| * @param id The id of the new member that has joined the system |
| * @param crashed True if member did not depart in an orderly manner. |
| */ |
| default void memberDeparted(DistributionManager distributionManager, InternalDistributedMember id, |
| boolean crashed) { |
| // implement if needed |
| } |
| |
| /** |
| * This method is invoked after the group membership service has suspected that a member is no |
| * longer alive, but has not yet been removed from the membership view |
| * |
| * @param distributionManager that is calling this listener |
| * @param id the suspected member |
| * @param whoSuspected the member that initiated suspect processing |
| * @param reason the reason the member was suspected |
| */ |
| default void memberSuspect(DistributionManager distributionManager, InternalDistributedMember id, |
| InternalDistributedMember whoSuspected, String reason) { |
| // implement if needed |
| } |
| |
| /** |
| * This is notification that more than 50% of member weight has been lost in a single view change. |
| * Notification is performed before the view has been installed. |
| * |
| * @param distributionManager that is calling this listener |
| * @param failures members that have been lost |
| * @param remaining members that remain |
| */ |
| default void quorumLost(DistributionManager distributionManager, |
| Set<InternalDistributedMember> failures, |
| List<InternalDistributedMember> remaining) { |
| // implement if needed |
| } |
| } |