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/async/AsyncLoggerContext.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.async;

import java.net.URI;
import java.util.concurrent.TimeUnit;

import org.apache.logging.log4j.core.Logger;
import org.apache.logging.log4j.core.LoggerContext;
import org.apache.logging.log4j.core.config.Configuration;
import org.apache.logging.log4j.core.config.DefaultConfiguration;
import org.apache.logging.log4j.core.jmx.RingBufferAdmin;
import org.apache.logging.log4j.message.MessageFactory;
import org.apache.logging.log4j.status.StatusLogger;

/**
 * {@code LoggerContext} that creates {@code AsyncLogger} objects.
 */
public class AsyncLoggerContext extends LoggerContext {

    private final AsyncLoggerDisruptor loggerDisruptor;

    public AsyncLoggerContext(final String name) {
        super(name);
        loggerDisruptor = new AsyncLoggerDisruptor(name);
    }

    public AsyncLoggerContext(final String name, final Object externalContext) {
        super(name, externalContext);
        loggerDisruptor = new AsyncLoggerDisruptor(name);
    }

    public AsyncLoggerContext(final String name, final Object externalContext, final URI configLocn) {
        super(name, externalContext, configLocn);
        loggerDisruptor = new AsyncLoggerDisruptor(name);
    }

    public AsyncLoggerContext(final String name, final Object externalContext, final String configLocn) {
        super(name, externalContext, configLocn);
        loggerDisruptor = new AsyncLoggerDisruptor(name);
    }

    @Override
    protected Logger newInstance(final LoggerContext ctx, final String name, final MessageFactory messageFactory) {
        return new AsyncLogger(ctx, name, messageFactory, loggerDisruptor);
    }

    @Override
    public void setName(final String name) {
        super.setName("AsyncContext[" + name + "]");
        loggerDisruptor.setContextName(name);
    }

    /*
     * (non-Javadoc)
     *
     * @see org.apache.logging.log4j.core.LoggerContext#start()
     */
    @Override
    public void start() {
        loggerDisruptor.start();
        super.start();
    }

    /*
     * (non-Javadoc)
     *
     * @see org.apache.logging.log4j.core.LoggerContext#start(org.apache.logging.log4j.core.config.Configuration)
     */
    @Override
    public void start(final Configuration config) {
        maybeStartHelper(config);
        super.start(config);
    }

    private void maybeStartHelper(final Configuration config) {
        // If no log4j configuration was found, there are no loggers
        // and there is no point in starting the disruptor (which takes up
        // significant memory and starts a thread).
        if (config instanceof DefaultConfiguration) {
            StatusLogger.getLogger().debug("[{}] Not starting Disruptor for DefaultConfiguration.", getName());
        } else {
            loggerDisruptor.start();
        }
    }

    @Override
    public boolean stop(final long timeout, final TimeUnit timeUnit) {
        setStopping();
        // first stop Disruptor
        loggerDisruptor.stop(timeout, timeUnit);
        super.stop(timeout, timeUnit);
        return true;
    }

    /**
     * Creates and returns a new {@code RingBufferAdmin} that instruments the ringbuffer of the {@code AsyncLogger}
     * objects in this {@code LoggerContext}.
     *
     * @return a new {@code RingBufferAdmin} that instruments the ringbuffer
     */
    public RingBufferAdmin createRingBufferAdmin() {
        return loggerDisruptor.createRingBufferAdmin(getName());
    }

    /**
     * Signals this context whether it is allowed to use ThreadLocal objects for efficiency.
     * @param useThreadLocals whether this context is allowed to use ThreadLocal objects
     */
    public void setUseThreadLocals(final boolean useThreadLocals) {
        loggerDisruptor.setUseThreadLocals(useThreadLocals);
    }
}

⏎ org/apache/logging/log4j/core/async/AsyncLoggerContext.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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