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/Log4jThreadFactory.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.ThreadFactory;
import java.util.concurrent.atomic.AtomicInteger;

/**
 * Creates {@link Log4jThread}s.
 *
 * @since 2.7
 */
public class Log4jThreadFactory implements ThreadFactory {

    private static final String PREFIX = "TF-";

    /**
     * Creates a new daemon thread factory.
     *
     * @param threadFactoryName
     *            The thread factory name.
     * @return a new daemon thread factory.
     */
    public static Log4jThreadFactory createDaemonThreadFactory(final String threadFactoryName) {
        return new Log4jThreadFactory(threadFactoryName, true, Thread.NORM_PRIORITY);
    }

    /**
     * Creates a new thread factory.
     *
     * This is mainly used for tests. Production code should be very careful with creating
     * non-daemon threads since those will block application shutdown
     * (see https://issues.apache.org/jira/browse/LOG4J2-1748).
     *
     * @param threadFactoryName
     *            The thread factory name.
     * @return a new daemon thread factory.
     */
    public static Log4jThreadFactory createThreadFactory(final String threadFactoryName) {
        return new Log4jThreadFactory(threadFactoryName, false, Thread.NORM_PRIORITY);
    }

    private static final AtomicInteger FACTORY_NUMBER = new AtomicInteger(1);
    private static final AtomicInteger THREAD_NUMBER = new AtomicInteger(1);
    private final boolean daemon;
    private final ThreadGroup group;
    private final int priority;
    private final String threadNamePrefix;

    /**
     * Constructs an initialized thread factory.
     *
     * @param threadFactoryName
     *            The thread factory name.
     * @param daemon
     *            Whether to create daemon threads.
     * @param priority
     *            The thread priority.
     */
    public Log4jThreadFactory(final String threadFactoryName, final boolean daemon, final int priority) {
        this.threadNamePrefix = PREFIX + FACTORY_NUMBER.getAndIncrement() + "-" + threadFactoryName + "-";
        this.daemon = daemon;
        this.priority = priority;
        final SecurityManager securityManager = System.getSecurityManager();
        this.group = securityManager != null ? securityManager.getThreadGroup()
                : Thread.currentThread().getThreadGroup();
    }

    @Override
    public Thread newThread(final Runnable runnable) {
        // Log4jThread prefixes names with "Log4j2-".
        final Thread thread = new Log4jThread(group, runnable, threadNamePrefix + THREAD_NUMBER.getAndIncrement(), 0);
        if (thread.isDaemon() != daemon) {
            thread.setDaemon(daemon);
        }
        if (thread.getPriority() != priority) {
            thread.setPriority(priority);
        }
        return thread;
    }

}

⏎ org/apache/logging/log4j/core/util/Log4jThreadFactory.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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