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/ZooKeeperCriticalThread.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;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * Represents critical thread. When there is an uncaught exception thrown by the
 * thread this will exit the system.
 */
public class ZooKeeperCriticalThread extends ZooKeeperThread {

    private static final Logger LOG = LoggerFactory.getLogger(ZooKeeperCriticalThread.class);
    private final ZooKeeperServerListener listener;

    public ZooKeeperCriticalThread(String threadName, ZooKeeperServerListener listener) {
        super(threadName);
        this.listener = listener;
    }

    /**
     * This will be used by the uncaught exception handler and make the system
     * exit.
     *
     * @param threadName
     *            - thread name
     * @param e
     *            - exception object
     */
    @Override
    protected void handleException(String threadName, Throwable e) {
        LOG.error("Severe unrecoverable error, from thread : {}", threadName, e);
        listener.notifyStopping(threadName, ExitCode.UNEXPECTED_ERROR.getValue());
        ServerMetrics.getMetrics().UNRECOVERABLE_ERROR_COUNT.add(1);
    }

}

⏎ org/apache/zookeeper/server/ZooKeeperCriticalThread.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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