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.plugins.convert;

import java.lang.invoke.MethodHandle;
import java.lang.invoke.MethodHandles;
import java.lang.invoke.MethodType;
import java.sql.Time;
import java.sql.Timestamp;
import java.util.Arrays;
import java.util.Date;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;

 * Utility methods for Date classes.
public final class DateTypeConverter {

    private static final Map<Class<? extends Date>, MethodHandle> CONSTRUCTORS = new ConcurrentHashMap<>();

    static {
        final MethodHandles.Lookup lookup = MethodHandles.publicLookup();
        for (final Class<? extends Date> dateClass : Arrays.asList(Date.class, java.sql.Date.class, Time.class,
            Timestamp.class)) {
            try {
                    lookup.findConstructor(dateClass, MethodType.methodType(void.class, long.class)));
            } catch (final NoSuchMethodException | IllegalAccessException ignored) {
                // these classes all have this exact constructor

     * Create a Date-related object from a timestamp in millis.
     * @param millis timestamp in millis
     * @param type   date type to use
     * @param <D>    date class to use
     * @return new instance of D or null if there was an error
    public static <D extends Date> D fromMillis(final long millis, final Class<D> type) {
        try {
            return (D) CONSTRUCTORS.get(type).invoke(millis);
        } catch (final Throwable ignored) {
            return null;

    private DateTypeConverter() {



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


Source Code for Apache Log4j JDK Logging Adapter

Source Code for Apache Log4j API

Downloading and Reviewing Apache Log4j Packages

⇑⇑ FAQ for Apache Log4j

2015-11-03, 92799👍, 0💬