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 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 Core Implementation 2.14.1 below.

⏎ org/apache/logging/log4j/core/lookup/Log4jLookup.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.core.lookup;

import java.io.File;
import java.net.URI;
import java.net.URISyntaxException;
import java.net.URL;

import org.apache.logging.log4j.core.LogEvent;
import org.apache.logging.log4j.core.config.ConfigurationSource;
import org.apache.logging.log4j.core.config.plugins.Plugin;
import org.apache.logging.log4j.status.StatusLogger;

/**
 * Lookup properties of Log4j
 */
@Plugin(name = "log4j", category = StrLookup.CATEGORY)
public class Log4jLookup extends AbstractConfigurationAwareLookup {

    public final static String KEY_CONFIG_LOCATION = "configLocation";
    public final static String KEY_CONFIG_PARENT_LOCATION = "configParentLocation";

    private static final org.apache.logging.log4j.Logger LOGGER = StatusLogger.getLogger();

    private static String asPath(final URI uri) {
        if (uri.getScheme() == null || uri.getScheme().equals("file")) {
            return uri.getPath();
        }
        return uri.toString();
    }

    private static URI getParent(final URI uri) throws URISyntaxException {
        final String s = uri.toString();
        final int offset = s.lastIndexOf('/');
        if (offset > -1) {
            return new URI(s.substring(0, offset));
        }
        return new URI("../");
    }

    @Override
    public String lookup(final LogEvent event, final String key) {
        if (configuration != null) {
            final ConfigurationSource configSrc = configuration.getConfigurationSource();
            final File file = configSrc.getFile();
            if (file != null) {
                switch (key) {
                    case KEY_CONFIG_LOCATION:
                        return file.getAbsolutePath();

                    case KEY_CONFIG_PARENT_LOCATION:
                        return file.getParentFile().getAbsolutePath();

                    default:
                        return null;
                }
            }

            final URL url = configSrc.getURL();
            if (url != null) {
                try {
                    switch (key) {
                        case KEY_CONFIG_LOCATION:
                            return asPath(url.toURI());

                        case KEY_CONFIG_PARENT_LOCATION:
                            return asPath(getParent(url.toURI()));

                        default:
                            return null;
                    }
                } catch (final URISyntaxException use) {
                    LOGGER.error(use);
                }
            }
        }

        return null;
    }
}

⏎ org/apache/logging/log4j/core/lookup/Log4jLookup.java

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
Download 

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