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/CoreLogger.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;

import java.util.logging.Level;
import java.util.logging.Logger;

/**
 * Log4j Core implementation of the JUL {@link Logger} class. <strong>Note that this implementation does
 * <em>not</em> use the {@link java.util.logging.Handler} class.</strong> Instead, logging is delegated to the
 * underlying Log4j {@link org.apache.logging.log4j.core.Logger} which uses
 * {@link org.apache.logging.log4j.core.Appender Appenders} instead.
 *
 * @since 2.1
 */
public class CoreLogger extends ApiLogger {

    private final org.apache.logging.log4j.core.Logger logger;

    /**
     * Constructs a Logger using a Log4j {@link org.apache.logging.log4j.core.Logger}.
     *
     * @param logger the underlying Logger to base this Logger on
     */
    CoreLogger(final org.apache.logging.log4j.core.Logger logger) {
        super(logger);
        this.logger = logger;
    }

    @Override
    public void setLevel(final Level level) throws SecurityException {
        super.doSetLevel(level); // checks permissions
        logger.setLevel(LevelTranslator.toLevel(level));
    }

    /**
     * Marks the underlying {@link org.apache.logging.log4j.core.Logger} as additive.
     *
     * @param additive {@code true} if this Logger should be additive
     * @see org.apache.logging.log4j.core.Logger#setAdditive(boolean)
     */
    @Override
    public synchronized void setUseParentHandlers(final boolean additive) {
        logger.setAdditive(additive);
    }

    /**
     * Indicates if the underlying {@link org.apache.logging.log4j.core.Logger} is additive. <strong>Note that the
     * Log4j version of JDK Loggers do <em>not</em> use Handlers.</strong>
     *
     * @return {@code true} if this Logger is additive, or {@code false} otherwise
     * @see org.apache.logging.log4j.core.Logger#isAdditive()
     */
    @Override
    public synchronized boolean getUseParentHandlers() {
        return logger.isAdditive();
    }

    @Override
    public Logger getParent() {
        final org.apache.logging.log4j.core.Logger parent = logger.getParent();
        return parent == null ? null : Logger.getLogger(parent.getName());
    }
}

⏎ org/apache/logging/log4j/jul/CoreLogger.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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