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Java client for Arcus memcached

There is a newer version: 1.13.2

/*
 * arcus-java-client : Arcus Java client
 * Copyright 2010-2014 NAVER Corp.
 *
 * 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.
 */
/* ENABLE_REPLICATION if */
package net.spy.memcached;

import net.spy.memcached.compat.SpyObject;

public abstract class MemcachedReplicaGroup extends SpyObject {
	protected final String group;
	protected MemcachedNode masterNode;
	protected MemcachedNode slaveNode;
	private boolean prevMasterPick;

	protected MemcachedReplicaGroup(final String groupName) {
		if (groupName == null)
			throw new IllegalArgumentException("Memcached in Replica Group must have group name");
		this.group = groupName;
	}

	public String toString() {
		return "[" + this.masterNode + ", " + this.slaveNode + "]";
	}

	public boolean isEmptyGroup() {
		return masterNode == null && slaveNode == null;
	}

	public abstract boolean setMemcachedNode(final MemcachedNode node);

	public abstract boolean deleteMemcachedNode(final MemcachedNode node);

	public String getGroupName() {
		return this.group;
	}

	public MemcachedNode getMasterNode() {
		return masterNode;
	}

	public MemcachedNode getSlaveNode() {
		return slaveNode;
	}

	public MemcachedNode getNodeForReplicaPick(ReplicaPick priority) {
		MemcachedNode node = null;

		switch (priority) {
			case MASTER:
				node = masterNode;
				break;
			case SLAVE:
				if (slaveNode != null && slaveNode.isActive()) {
					node = slaveNode;
				} else {
					node = masterNode;
				}
				break;
			case RR:
				if (prevMasterPick && slaveNode != null && slaveNode.isActive()) {
					node = slaveNode;
				} else {
					node = masterNode;
				}
				prevMasterPick = prevMasterPick ? false : true;
				break;
			default: // This case never exist.
				break;
		}
		return node; 
	}

	public abstract boolean changeRole();

	public static String getGroupNameForNode(final MemcachedNode node) {
		return ((ArcusReplNodeAddress)node.getSocketAddress()).getGroupName();
	}
}
/* ENABLE_REPLICATION end */