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 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 1.2 Bridge 2.14.1 below.

⏎ org/apache/log4j/xml/XmlConfigurationFactory.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.log4j.xml;

import org.apache.log4j.config.Log4j1Configuration;
import org.apache.logging.log4j.core.LoggerContext;
import org.apache.logging.log4j.core.config.Configuration;
import org.apache.logging.log4j.core.config.ConfigurationFactory;
import org.apache.logging.log4j.core.config.ConfigurationSource;
import org.apache.logging.log4j.core.config.Order;
import org.apache.logging.log4j.core.config.plugins.Plugin;
import org.apache.logging.log4j.status.StatusLogger;
import org.apache.logging.log4j.util.PropertiesUtil;

/**
 * Constructs a Configuration usable in Log4j 2 from a Log4j 1 configuration file.
 */
@Plugin(name = "Log4j1XmlConfigurationFactory", category = ConfigurationFactory.CATEGORY)
@Order(2)
public class XmlConfigurationFactory extends ConfigurationFactory {
    private static final org.apache.logging.log4j.Logger LOGGER = StatusLogger.getLogger();

    /**
     * File name prefix for test configurations.
     */
    protected static final String TEST_PREFIX = "log4j-test";

    /**
     * File name prefix for standard configurations.
     */
    protected static final String DEFAULT_PREFIX = "log4j";

    @Override
    protected String[] getSupportedTypes() {
        if (!PropertiesUtil.getProperties().getBooleanProperty(ConfigurationFactory.LOG4J1_EXPERIMENTAL, Boolean.FALSE)) {
            return null;
        }
        return new String[] {".xml"};
    }

    @Override
    public Configuration getConfiguration(LoggerContext loggerContext, ConfigurationSource source) {
        int interval = PropertiesUtil.getProperties().getIntegerProperty(Log4j1Configuration.MONITOR_INTERVAL, 0);
        return new XmlConfiguration(loggerContext, source, interval);
    }

    @Override
    protected String getTestPrefix() {
        return TEST_PREFIX;
    }

    @Override
    protected String getDefaultPrefix() {
        return DEFAULT_PREFIX;
    }

    @Override
    protected String getVersion() {
        return LOG4J1_VERSION;
    }
}

⏎ org/apache/log4j/xml/XmlConfigurationFactory.java

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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