Apache Log4j Core Implementation provides the functional components of the logging system. Users are free to create their own plugins and include them in the logging configuration. Apache Log4j Core is a required module to use Apache Log4j.

Bytecode (Java 8) for Apache Log4j Core Implementation is provided in a separate JAR file like log4j-core-2.14.1.jar.

Source Code files for Apache Log4j API are provided in both binary packge like apache-log4j-2.14.1-bin.zip and source package like apache-log4j-2.14.1-src.zip. You can download them at Apache Log4j Website.

You can also browse Source Code files for Apache Log4j Core Implementation 2.14.1 below.

⏎ org/apache/logging/log4j/core/util/ExecutorServices.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.logging.log4j.core.util;

import java.util.concurrent.ExecutorService;
import java.util.concurrent.TimeUnit;

import org.apache.logging.log4j.Logger;
import org.apache.logging.log4j.status.StatusLogger;

public class ExecutorServices {

    private static final Logger LOGGER = StatusLogger.getLogger();

    /**
     * Shuts down the given {@link ExecutorService} in an orderly fashion. Disables new tasks from submission and then
     * waits for existing tasks to terminate. Eventually cancels running tasks if too much time elapses.
     * <p>
     * If the timeout is 0, then a plain shutdown takes place.
     * </p>
     *
     * @param executorService
     *            the pool to shutdown.
     * @param timeout
     *            the maximum time to wait, or 0 to not wait for existing tasks to terminate.
     * @param timeUnit
     *            the time unit of the timeout argument
     * @param source
     *            use this string in any log messages.
     * @return {@code true} if the given executor terminated and {@code false} if the timeout elapsed before
     *         termination.
     */
    public static boolean shutdown(final ExecutorService executorService, final long timeout, final TimeUnit timeUnit, final String source) {
        if (executorService == null || executorService.isTerminated()) {
            return true;
        }
        executorService.shutdown(); // Disable new tasks from being submitted
        if (timeout > 0 && timeUnit == null) {
            throw new IllegalArgumentException(
                    String.format("%s can't shutdown %s when timeout = %,d and timeUnit = %s.", source, executorService,
                            timeout, timeUnit));
        }
        if (timeout > 0) {
            try {
                // Wait a while for existing tasks to terminate
                if (!executorService.awaitTermination(timeout, timeUnit)) {
                    executorService.shutdownNow(); // Cancel currently executing tasks
                    // Wait a while for tasks to respond to being cancelled
                    if (!executorService.awaitTermination(timeout, timeUnit)) {
                        LOGGER.error("{} pool {} did not terminate after {} {}", source, executorService, timeout,
                                timeUnit);
                    }
                    return false;
                }
            } catch (final InterruptedException ie) {
                // (Re-)Cancel if current thread also interrupted
                executorService.shutdownNow();
                // Preserve interrupt status
                Thread.currentThread().interrupt();
            }
        } else {
            executorService.shutdown();
        }
        return true;
    }

}

⏎ org/apache/logging/log4j/core/util/ExecutorServices.java

Or download all of them as a single archive file:

File name: log4j-core-2.14.1-sources.jar
File size: 1281358 bytes
Release date: 2021-03-06
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