/*
* Copyright (c) 2008-2017, Hazelcast, Inc. All Rights Reserved.
*
* Licensed 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 com.hazelcast.internal.cluster.impl;
import com.hazelcast.instance.Node;
import com.hazelcast.nio.Address;
import java.util.concurrent.BlockingDeque;
/**
* Listens for {@code SplitBrainJoinMessage}s and adds them for processing by split brain handler. Each messages is added
* to the head of a {@code BlockingDeque}, so that polling the {@code BlockingDeque} will return the message received last
* (thus operating as a stack).
*/
public class SplitBrainMulticastListener implements MulticastListener {
private final Node node;
private final BlockingDeque<SplitBrainJoinMessage> deque;
public SplitBrainMulticastListener(Node node, BlockingDeque<SplitBrainJoinMessage> deque) {
this.node = node;
this.deque = deque;
}
public void onMessage(Object msg) {
if (msg instanceof SplitBrainJoinMessage) {
SplitBrainJoinMessage joinRequest = (SplitBrainJoinMessage) msg;
Address thisAddress = node.getThisAddress();
// only master nodes execute the SplitBrainHandler that processes SplitBrainJoinMessages
if (!thisAddress.equals(joinRequest.getAddress()) && node.isMaster()) {
deque.addFirst(joinRequest);
}
}
}
}