Apache ZooKeeper is an open-source server which enables highly reliable distributed coordination.

Apache ZooKeeper Server Source Code files are provided in the source packge (apache-zookeeper-3.7.0.tar.gz). You can download it at Apache ZooKeeper Website.

You can also browse Apache ZooKeeper Server Source Code below:

⏎ org/apache/zookeeper/server/quorum/StateSummary.java

/*
 * 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.zookeeper.server.quorum;

/**
 * This class encapsulates the state comparison logic. Specifically,
 * how two different states are compared.
 */
public class StateSummary {

    private long currentEpoch;
    private long lastZxid;
    public StateSummary(long currentEpoch, long lastZxid) {
        this.currentEpoch = currentEpoch;
        this.lastZxid = lastZxid;
    }

    public long getCurrentEpoch() {
        return currentEpoch;
    }

    public long getLastZxid() {
        return lastZxid;
    }

    public boolean isMoreRecentThan(StateSummary ss) {
        return (currentEpoch > ss.currentEpoch) || (currentEpoch == ss.currentEpoch && lastZxid > ss.lastZxid);
    }
    @Override
    public boolean equals(Object obj) {
        if (!(obj instanceof StateSummary)) {
            return false;
        }
        StateSummary ss = (StateSummary) obj;
        return currentEpoch == ss.currentEpoch && lastZxid == ss.lastZxid;
    }

    @Override
    public int hashCode() {
        return (int) (currentEpoch ^ lastZxid);
    }

}

⏎ org/apache/zookeeper/server/quorum/StateSummary.java

Or download all of them as a single archive file:

File name: zookeeper-server-3.7.0-fyi.zip
File size: 871011 bytes
Release date: 2021-05-17
Download 

⇒ Apache ZooKeeper 3.7.0 Jute Source Code

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