Source Code for Apache Log4j Core Implementation

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 and source package like You can download them at Apache Log4j Website.

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



 * 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
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * See the license for the specific language governing permissions and
 * limitations under the license.
package org.apache.logging.log4j.core.config;

import java.util.Objects;

import org.apache.logging.log4j.Level;
import org.apache.logging.log4j.core.Core;
import org.apache.logging.log4j.core.config.plugins.Plugin;
import org.apache.logging.log4j.core.config.plugins.PluginAttribute;
import org.apache.logging.log4j.core.config.plugins.PluginFactory;
import org.apache.logging.log4j.status.StatusLogger;

 * Descriptor of a custom Level object that is created via configuration.
@Plugin(name = "CustomLevel", category = Core.CATEGORY_NAME, printObject = true)
public final class CustomLevelConfig {

    private final String levelName;
    private final int intLevel;

    private CustomLevelConfig(final String levelName, final int intLevel) {
        this.levelName = Objects.requireNonNull(levelName, "levelName is null");
        this.intLevel = intLevel;

     * Creates a CustomLevelConfig object. This also defines the Level object with a call to
     * {@link Level#forName(String, int)}.
     * @param levelName name of the custom level.
     * @param intLevel the intLevel that determines where this level resides relative to the built-in levels
     * @return A CustomLevelConfig object.
    public static CustomLevelConfig createLevel(// @formatter:off
            @PluginAttribute("name") final String levelName,
            @PluginAttribute("intLevel") final int intLevel) {
        // @formatter:on

        StatusLogger.getLogger().debug("Creating CustomLevel(name='{}', intValue={})", levelName, intLevel);
        Level.forName(levelName, intLevel);
        return new CustomLevelConfig(levelName, intLevel);

     * Returns the custom level name.
     * @return the custom level name
    public String getLevelName() {
        return levelName;

     * Returns the custom level intLevel that determines the strength of the custom level relative to the built-in
     * levels.
     * @return the custom level intLevel
    public int getIntLevel() {
        return intLevel;

    public int hashCode() {
        return intLevel ^ levelName.hashCode();

    public boolean equals(final Object object) {
        if (this == object) {
            return true;
        if (!(object instanceof CustomLevelConfig)) {
            return false;
        final CustomLevelConfig other = (CustomLevelConfig) object;
        return this.intLevel == other.intLevel && this.levelName.equals(other.levelName);

    public String toString() {
        return "CustomLevel[name=" + levelName + ", intLevel=" + intLevel + "]";



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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