Source Code for Apache Log4j 1.2 Bridge

Apache Log4j 1.2 Bridge allows applications coded to use Log4j 1.2 API to use Log4j 2 instead.

Bytecode (Java 8) for Apache Log4j 1.2 Bridge is provided in a separate JAR file like log4j-1.2-api-2.14.1.jar.

Source Code files for Apache Log4j 1.2 Bridge 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 1.2 Bridge 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.log4j;

import java.util.HashMap;
import java.util.Hashtable;
import java.util.Map;

import org.apache.logging.log4j.ThreadContext;

 * This class behaves just like Log4j's MDC would - and so can cause issues with the redeployment of web
 * applications if the Objects stored in the threads Map cannot be garbage collected.
public final class MDC {

    private static ThreadLocal<Map<String, Object>> localMap =
        new InheritableThreadLocal<Map<String, Object>>() {
            protected Map<String, Object> initialValue() {
                return new HashMap<>();

            protected Map<String, Object> childValue(final Map<String, Object> parentValue) {
                return parentValue == null ? new HashMap<>() : new HashMap<>(parentValue);

    private MDC() {

    public static void put(final String key, final String value) {
        localMap.get().put(key, value);
        ThreadContext.put(key, value);

    public static void put(final String key, final Object value) {
        localMap.get().put(key, value);
        ThreadContext.put(key, value.toString());

    public static Object get(final String key) {
        return localMap.get().get(key);

    public static void remove(final String key) {

    public static void clear() {

    public static Hashtable<String, Object> getContext() {
        return new Hashtable<>(localMap.get());



Or download all of them as a single archive file:

File name: log4j-1.2-api-2.14.1-sources.jar
File size: 168047 bytes
Release date: 2021-03-06


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