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/AsyncQueueFullMessageUtil.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 org.apache.logging.log4j.status.StatusLogger;

/**
 * <b>Consider this class private.</b>
 * <p>
 * Logs a warning to the {@link StatusLogger} when events are logged out of order to avoid deadlocks.
 * </p>
 */
public final class AsyncQueueFullMessageUtil {
    private AsyncQueueFullMessageUtil() {
        // Utility Class
    }

    /**
     * Logs a warning to the {@link StatusLogger} explaining why a message appears out of order in the appender.
     */
    public static void logWarningToStatusLogger() {
        StatusLogger.getLogger()
                .warn("LOG4J2-2031: Log4j2 logged an event out of order to prevent deadlock caused by domain " +
                        "objects logging from their toString method when the async queue is full");
    }
}

⏎ org/apache/logging/log4j/core/async/AsyncQueueFullMessageUtil.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
Download 

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