com.lambdaworks.redis.masterslave.MasterSlaveUtils Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of lettuce Show documentation

Advanced and thread-safe Java Redis client for synchronous, asynchronous, and reactive usage. Supports Cluster, Sentinel, Pipelining, Auto-Reconnect, Codecs and much more.

The newest version!

/*
 * Copyright 2011-2016 the original author or authors.
 *
 * 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.lambdaworks.redis.masterslave;

import java.util.Collection;

import com.lambdaworks.redis.RedisURI;
import com.lambdaworks.redis.codec.Utf8StringCodec;
import com.lambdaworks.redis.models.role.RedisNodeDescription;

/**
 * @author Mark Paluch
 */
class MasterSlaveUtils {
    static final Utf8StringCodec CODEC = new Utf8StringCodec();

    /**
     * Check if properties changed.
     * 
     * @param o1 the first object to be compared.
     * @param o2 the second object to be compared.
     * @return {@literal true} if {@code MASTER} or {@code SLAVE} flags changed or the URIs are changed.
     */
    static boolean isChanged(Collection o1, Collection o2) {

        if (o1.size() != o2.size()) {
            return true;
        }

        for (RedisNodeDescription base : o2) {
            if (!essentiallyEqualsTo(base, findNodeByUri(o1, base.getUri()))) {
                return true;
            }
        }

        return false;
    }

    /**
     * Lookup a {@link RedisNodeDescription} by {@link RedisURI}.
     * 
     * @param nodes
     * @param lookupUri
     * @return the {@link RedisNodeDescription} or {@literal null}
     */
    static RedisNodeDescription findNodeByUri(Collection nodes, RedisURI lookupUri) {
        return findNodeByHostAndPort(nodes, lookupUri.getHost(), lookupUri.getPort());
    }

    /**
     * Lookup a {@link RedisNodeDescription} by {@code host} and {@code port}.
     * 
     * @param nodes
     * @param host
     * @param port
     * @return the {@link RedisNodeDescription} or {@literal null}
     */
    static RedisNodeDescription findNodeByHostAndPort(Collection nodes, String host, int port) {
        for (RedisNodeDescription node : nodes) {
            RedisURI nodeUri = node.getUri();
            if (nodeUri.getHost().equals(host) && nodeUri.getPort() == port) {
                return node;
            }
        }
        return null;
    }

    /**
     * Check for {@code MASTER} or {@code SLAVE} roles and the URI.
     * 
     * @param o1 the first object to be compared.
     * @param o2 the second object to be compared.
     * @return {@literal true} if {@code MASTER} or {@code SLAVE} flags changed or the URI changed.
     */
    static boolean essentiallyEqualsTo(RedisNodeDescription o1, RedisNodeDescription o2) {

        if (o2 == null) {
            return false;
        }

        if (o1.getRole() != o2.getRole()) {
            return false;
        }

        if (!o1.getUri().equals(o2.getUri())) {
            return false;
        }

        return true;
    }

}