Apache Log4j JDK Logging Adapter is a custom implementation of java.util.logging.LogManager that uses Log4j. This adapter can be used with either the Log4j API or Log4j Core.

Bytecode (Java 8) for Apache Log4j JDK Logging Adapter is provided in a separate JAR file like log4j-jul-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 JDK Logging Adapter 2.14.1 below.

⏎ org/apache/logging/log4j/jul/Constants.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.jul;

/**
 * Constants for the JUL adapter.
 *
 * @since 2.1
 */
public final class Constants {

    /**
     * Name of the Log4j property to set to override the {@link AbstractLoggerAdapter} to be used. By
     * default, when this property is not set, an appropriate LoggerAdaptor is chosen based on the presence of
     * {@code log4j-core}.
     */
    public static final String LOGGER_ADAPTOR_PROPERTY = "log4j.jul.LoggerAdapter";

    /**
     * The Log4j property to set to a custom implementation of {@link org.apache.logging.log4j.jul.LevelConverter}. The specified class must have
     * a default constructor.
     */
    public static final String LEVEL_CONVERTER_PROPERTY = "log4j.jul.levelConverter";

    static final String CORE_LOGGER_CLASS_NAME = "org.apache.logging.log4j.core.Logger";
    static final String CORE_LOGGER_ADAPTER_CLASS_NAME = "org.apache.logging.log4j.jul.CoreLoggerAdapter";
    static final String API_LOGGER_ADAPTER_CLASS_NAME = "org.apache.logging.log4j.jul.ApiLoggerAdapter";

    private Constants() {
    }
}

⏎ org/apache/logging/log4j/jul/Constants.java

Or download all of them as a single archive file:

File name: log4j-jul-2.14.1-sources.jar
File size: 24567 bytes
Release date: 2021-03-06
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