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/config/Configuration.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.config;

import java.util.List;
import java.util.Map;

import org.apache.logging.log4j.Level;
import org.apache.logging.log4j.core.Appender;
import org.apache.logging.log4j.core.Filter;
import org.apache.logging.log4j.core.LogEvent;
import org.apache.logging.log4j.core.Logger;
import org.apache.logging.log4j.core.LoggerContext;
import org.apache.logging.log4j.core.async.AsyncLoggerConfigDelegate;
import org.apache.logging.log4j.core.filter.Filterable;
import org.apache.logging.log4j.core.lookup.StrSubstitutor;
import org.apache.logging.log4j.core.net.Advertiser;
import org.apache.logging.log4j.core.script.ScriptManager;
import org.apache.logging.log4j.core.util.NanoClock;
import org.apache.logging.log4j.core.util.WatchManager;

/**
 * Interface that must be implemented to create a configuration.
 * <p>
 * Custom implementations are recommended to extend {@link AbstractConfiguration}.
 * </p>
 *
 * @see AbstractConfiguration
 * @see org.apache.logging.log4j.core.LifeCycle2
 */
public interface Configuration extends Filterable {

    /** Key for storing the Context properties. */
    String CONTEXT_PROPERTIES = "ContextProperties";

    /**
     * Returns the configuration name.
     *
     * @return the name of the configuration.
     */
    String getName();

    /**
     * Locates the appropriate LoggerConfig for a Logger name. This will remove tokens from the package name as
     * necessary or return the root LoggerConfig if no other matches were found.
     *
     * @param name The Logger name.
     * @return The located LoggerConfig.
     */
    LoggerConfig getLoggerConfig(String name);

    /**
     * Returns the Appender with the specified name.
     *
     * @param <T>  The expected Appender type.
     * @param name The name of the Appender.
     * @return the Appender with the specified name or null if the Appender cannot be located.
     */
    <T extends Appender> T getAppender(String name);

    /**
     * Returns a Map containing all the Appenders and their name.
     *
     * @return A Map containing each Appender's name and the Appender object.
     */
    Map<String, Appender> getAppenders();

    void addAppender(final Appender appender);

    Map<String, LoggerConfig> getLoggers();

    void addLoggerAppender(Logger logger, Appender appender);

    void addLoggerFilter(Logger logger, Filter filter);

    void setLoggerAdditive(Logger logger, boolean additive);

    void addLogger(final String name, final LoggerConfig loggerConfig);

    void removeLogger(final String name);

    /**
     * Returns the list of packages to scan for plugins for this Configuration.
     *
     * @return the list of plugin packages.
     * @since 2.1
     */
    List<String> getPluginPackages();

    Map<String, String> getProperties();

    /**
     * Returns the root Logger.
     *
     * @return the root Logger.
     */
    LoggerConfig getRootLogger();

    void addListener(ConfigurationListener listener);

    void removeListener(ConfigurationListener listener);

    StrSubstitutor getStrSubstitutor();

    void createConfiguration(Node node, LogEvent event);

    <T> T getComponent(String name);

    void addComponent(String name, Object object);

    void setAdvertiser(Advertiser advertiser);

    Advertiser getAdvertiser();

    boolean isShutdownHookEnabled();

    long getShutdownTimeoutMillis();

    ConfigurationScheduler getScheduler();

    /**
     * Returns the source of this configuration.
     *
     * @return the source of this configuration, never {@code null}, but may be
     * {@link org.apache.logging.log4j.core.config.ConfigurationSource#NULL_SOURCE}
     * or
     * {@link org.apache.logging.log4j.core.config.ConfigurationSource#COMPOSITE_SOURCE}
     */
    ConfigurationSource getConfigurationSource();

    /**
     * <p>
     * Returns a list of descriptors of the custom levels defined in the current configuration. The returned list does
     * <em>not</em> include custom levels that are defined in code with direct calls to {@link Level#forName(String, int)}.
     * </p>
     * <p>
     * Note that the list does not include levels of previous configurations. For example, suppose a configuration
     * contains custom levels A, B and C. The configuration is then modified to contain custom levels B, C and D. For
     * the new configuration, this method will return only {B, C, D}, that is, only the custom levels defined in
     * <em>this</em> configuration. The previously defined level A still exists (and can be obtained with
     * {@link Level#getLevel(String)}), it is just not in the current configuration. {@link Level#values()} will return
     * {A, B, C, D and the built-in levels}.
     * </p>
     *
     * @return the custom levels defined in the current configuration
     */
    List<CustomLevelConfig> getCustomLevels();

    ScriptManager getScriptManager();

    /**
     * Returns the {@code AsyncLoggerConfigDelegate} shared by all
     * {@code AsyncLoggerConfig} instances defined in this Configuration.
     *
     * @return the {@code AsyncLoggerConfigDelegate}
     */
    AsyncLoggerConfigDelegate getAsyncLoggerConfigDelegate();

    /**
     * Return the WatchManager.
     *
     * @return the WatchManager.
     */
    WatchManager getWatchManager();

    /*
     * (non-Javadoc)
     *
     * @see
     * org.apache.logging.log4j.core.config.ReliabilityStrategyFactory#getReliabilityStrategy(org.apache.logging.log4j
     * .core.config.LoggerConfig)
     */

    ReliabilityStrategy getReliabilityStrategy(LoggerConfig loggerConfig);

    /**
     * Returns the {@link NanoClock} instance for this configuration.
     *
     * @return the nano clock
     */
    NanoClock getNanoClock();

    /**
     * Sets the {@link NanoClock} instance for this configuration.
     *
     * @param nanoClock the new nano clock for this configuration. Must be non-null.
     */
    void setNanoClock(NanoClock nanoClock);

    /**
     * Gets the logger context.
     *
     * @return the logger context.
     */
    LoggerContext getLoggerContext();
}

⏎ org/apache/logging/log4j/core/config/Configuration.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
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