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.reflect.InvocationTargetException;
import java.lang.reflect.Method;

import org.apache.logging.log4j.Logger;
import org.apache.logging.log4j.status.StatusLogger;
import org.apache.logging.log4j.util.LoaderUtil;

 * @Since 2.9
public class Base64Converter {

    private static final Logger LOGGER = StatusLogger.getLogger();
    private static Method method = null;
    private static Object decoder = null;

    static {
        try {
            // Base64 is available in Java 8 and up.
            Class<?> clazz = LoaderUtil.loadClass("java.util.Base64");
            final Method getDecoder = clazz.getMethod("getDecoder", (Class[]) null);
            decoder = getDecoder.invoke(null, (Object[]) null);
            clazz = decoder.getClass();
            method = clazz.getMethod("decode", String.class);
        } catch (final ClassNotFoundException | NoSuchMethodException | IllegalAccessException |
            InvocationTargetException ex) {
            // ignore
        if (method == null) {
            try {
                // DatatypeConverter is not in the default module in Java 9.
                final Class<?> clazz = LoaderUtil.loadClass("javax.xml.bind.DatatypeConverter");
                method = clazz.getMethod("parseBase64Binary", String.class);
            } catch (final ClassNotFoundException ex) {
                LOGGER.error("No Base64 Converter is available");
            } catch (final NoSuchMethodException ex) {


    public static byte[] parseBase64Binary(final String encoded) {
        if (method == null) {
            LOGGER.error("No base64 converter");
        } else {
            try {
                return (byte[]) method.invoke(decoder, encoded);
            } catch (final IllegalAccessException | InvocationTargetException ex) {
                LOGGER.error("Error decoding string - " + ex.getMessage());
        return new byte[0];



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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