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/builder/api/ConfigurationBuilder.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.builder.api;

import java.io.IOException;
import java.io.OutputStream;
import java.util.concurrent.TimeUnit;

import org.apache.logging.log4j.Level;
import org.apache.logging.log4j.core.Filter;
import org.apache.logging.log4j.core.LoggerContext;
import org.apache.logging.log4j.core.config.Configuration;
import org.apache.logging.log4j.core.config.ConfigurationSource;
import org.apache.logging.log4j.core.util.Builder;

/**
 * Interface for building logging configurations.
 * @param <T> The Configuration type created by this builder.
 * @since 2.4
 */
public interface ConfigurationBuilder<T extends Configuration> extends Builder<T> {


    /**
     * Adds a ScriptComponent.
     * @param builder The ScriptComponentBuilder with all of its attributes and sub components set.
     * @return this builder instance.
     */
    ConfigurationBuilder<T> add(ScriptComponentBuilder builder);

    /**
     * Adds a ScriptFileComponent.
     * @param builder The ScriptFileComponentBuilder with all of its attributes and sub components set.
     * @return this builder instance.
     */
    ConfigurationBuilder<T> add(ScriptFileComponentBuilder builder);

    /**
     * Adds an AppenderComponent.
     * @param builder The AppenderComponentBuilder with all of its attributes and sub components set.
     * @return this builder instance.
     */
    ConfigurationBuilder<T> add(AppenderComponentBuilder builder);

    /**
     * Adds a CustomLevel component.
     * @param builder The CustomLevelComponentBuilder with all of its attributes set.
     * @return this builder instance.
     */
    ConfigurationBuilder<T> add(CustomLevelComponentBuilder builder);

    /**
     * Adds a Filter component.
     * @param builder the FilterComponentBuilder with all of its attributes and sub components set.
     * @return this builder instance.
     */
    ConfigurationBuilder<T> add(FilterComponentBuilder builder);

    /**
     * Adds a Logger component.
     * @param builder The LoggerComponentBuilder with all of its attributes and sub components set.
     * @return this builder instance.
     */
    ConfigurationBuilder<T> add(LoggerComponentBuilder builder);

    /**
     * Adds the root Logger component.
     * @param builder The RootLoggerComponentBuilder with all of its attributes and sub components set.
     * @return this builder instance.
     */
    ConfigurationBuilder<T> add(RootLoggerComponentBuilder builder);

    /**
     * Adds a Property key and value.
     * @param key The property key.
     * @param value The property value.
     * @return this builder instance.
     */
    ConfigurationBuilder<T> addProperty(String key, String value);


    /**
     * Returns a builder for creating Async Loggers.
     * @param name The name of the Logger.
     * @param language The script language
     * @param text The script to execute.
     * @return A new ScriptComponentBuilder.
     */
    ScriptComponentBuilder newScript(String name, String language, String text);

    /**
     * Returns a builder for creating Async Loggers.
     * @param path The location of the script file.
     * @return A new ScriptFileComponentBuilder.
     */
    ScriptFileComponentBuilder newScriptFile(String path);


    /**
     * Returns a builder for creating Async Loggers.
     * @param name The name of the script file.
     * @param path The location of the script file.
     * @return A new ScriptFileComponentBuilder.
     */
    ScriptFileComponentBuilder newScriptFile(String name, String path);


    /**
     * Returns a builder for creating Appenders.
     * @param name The name of the Appender.
     * @param pluginName The Plugin type of the Appender.
     * @return A new AppenderComponentBuilder.
     */
    AppenderComponentBuilder newAppender(String name, String pluginName);

    /**
     * Returns a builder for creating AppenderRefs.
     * @param ref The name of the Appender being referenced.
     * @return A new AppenderRefComponentBuilder.
     */
    AppenderRefComponentBuilder newAppenderRef(String ref);


    /**
     * Returns a builder for creating Async Loggers.
     * @param name The name of the Logger.
     * @return A new LoggerComponentBuilder.
     */
    LoggerComponentBuilder newAsyncLogger(String name);

    /**
     * Returns a builder for creating Async Loggers.
     * @param name The name of the Logger.
     * @param includeLocation If true include location information.
     * @return A new LoggerComponentBuilder.
     */
    LoggerComponentBuilder newAsyncLogger(String name, boolean includeLocation);

    /**
     * Returns a builder for creating Async Loggers.
     * @param name The name of the Logger.
     * @param level The logging Level to be assigned to the Logger.
     * @return A new LoggerComponentBuilder.
     */
    LoggerComponentBuilder newAsyncLogger(String name, Level level);

    /**
     * Returns a builder for creating Async Loggers.
     * @param name The name of the Logger.
     * @param level The logging Level to be assigned to the Logger.
     * @param includeLocation If true include location information.
     * @return A new LoggerComponentBuilder.
     */
    LoggerComponentBuilder newAsyncLogger(String name, Level level, boolean includeLocation);

    /**
     * Returns a builder for creating Async Loggers.
     * @param name The name of the Logger.
     * @param level The logging Level to be assigned to the Logger.
     * @return A new LoggerComponentBuilder.
     */
    LoggerComponentBuilder newAsyncLogger(String name, String level);

    /**
     * Returns a builder for creating Async Loggers.
     * @param name The name of the Logger.
     * @param level The logging Level to be assigned to the Logger.
     * @param includeLocation If true include location information.
     * @return A new LoggerComponentBuilder.
     */
    LoggerComponentBuilder newAsyncLogger(String name, String level, boolean includeLocation);

    /**
     * Returns a builder for creating the async root Logger.
     * @return A new RootLoggerComponentBuilder.
     */
    RootLoggerComponentBuilder newAsyncRootLogger();


    /**
     * Returns a builder for creating the async root Logger.
     * @param includeLocation If true include location information.
     * @return A new RootLoggerComponentBuilder.
     */
    RootLoggerComponentBuilder newAsyncRootLogger(boolean includeLocation);

    /**
     * Returns a builder for creating the async root Logger.
     * @param level The logging Level to be assigned to the root Logger.
     * @return A new RootLoggerComponentBuilder.
     */
    RootLoggerComponentBuilder newAsyncRootLogger(Level level);


    /**
     * Returns a builder for creating the async root Logger.
     * @param level The logging Level to be assigned to the root Logger.
     * @param includeLocation If true include location information.
     * @return A new RootLoggerComponentBuilder.
     */
    RootLoggerComponentBuilder newAsyncRootLogger(Level level, boolean includeLocation);

    /**
     * Returns a builder for creating the async root Logger.
     * @param level The logging Level to be assigned to the root Logger.
     * @return A new RootLoggerComponentBuilder.
     */
    RootLoggerComponentBuilder newAsyncRootLogger(String level);


    /**
     * Returns a builder for creating the async root Logger.
     * @param level The logging Level to be assigned to the root Logger.
     * @param includeLocation If true include location information.
     * @return A new RootLoggerComponentBuilder.
     */
    RootLoggerComponentBuilder newAsyncRootLogger(String level, boolean includeLocation);

    /**
     * Returns a builder for creating generic components.
     * @param <B> ComponentBuilder target type
     * @param pluginName The Plugin type of the component.
     * @return A new ComponentBuilder.
     */
    <B extends ComponentBuilder<B>> ComponentBuilder<B> newComponent(String pluginName);

    /**
     * Returns a builder for creating generic components.
     * @param <B> ComponentBuilder target type
     * @param name The name of the component (may be null).
     * @param pluginName The Plugin type of the component.
     * @return A new ComponentBuilder.
     */
    <B extends ComponentBuilder<B>> ComponentBuilder<B> newComponent(String name, String pluginName);

    /**
     * Returns a builder for creating generic components.
     * @param <B> ComponentBuilder target type
     * @param name The name of the component (may be null).
     * @param pluginName The Plugin type of the component.
     * @param value The value of the component.
     * @return A new ComponentBuilder.
     */
    <B extends ComponentBuilder<B>> ComponentBuilder<B> newComponent(String name, String pluginName, String value);

    /**
     * Returns a builder for creating Property:s
     * @param name The name of the property.
     * @param value The value of the component.
     * @return A new PropertyComponentBuilder.
     */
    PropertyComponentBuilder newProperty(String name, String value);

    /**
     * Returns a builder for creating KeyValuePair:s
     * @param key The name
     * @param value The value
     * @return A new KeyValuePairComponentBuilder.
     */
    KeyValuePairComponentBuilder newKeyValuePair(String key, String value);

    /**
     * Returns a builder for creating CustomLevels
     * @param name The name of the custom level.
     * @param level The integer value to be assigned to the level.
     * @return A new CustomLevelComponentBuilder.
     */
    CustomLevelComponentBuilder newCustomLevel(String name, int level);

    /**
     * Returns a builder for creating Filters.
     * @param pluginName The Plugin type of the Filter.
     * @param onMatch "ACCEPT", "DENY", or "NEUTRAL"
     * @param onMismatch "ACCEPT", "DENY", or "NEUTRAL"
     * @return A new FilterComponentBuilder.
     */
    FilterComponentBuilder newFilter(String pluginName, Filter.Result onMatch, Filter.Result onMismatch);

    /**
     * Returns a builder for creating Filters.
     * @param pluginName The Plugin type of the Filter.
     * @param onMatch "ACCEPT", "DENY", or "NEUTRAL"
     * @param onMismatch "ACCEPT", "DENY", or "NEUTRAL"
     * @return A new FilterComponentBuilder.
     */
    FilterComponentBuilder newFilter(String pluginName, String onMatch, String onMismatch);

    /**
     * Returns a builder for creating Layouts.
     * @param pluginName The Plugin type of the Layout.
     * @return A new LayoutComponentBuilder.
     */
    LayoutComponentBuilder newLayout(String pluginName);

    /**
     * Returns a builder for creating Loggers.
     * @param name The name of the Logger.
     * @return A new LoggerComponentBuilder.
     */
    LoggerComponentBuilder newLogger(String name);

    /**
     * Returns a builder for creating Loggers.
     * @param name The name of the Logger.
     * @param includeLocation If true include location information.
     * @return A new LoggerComponentBuilder.
     */
    LoggerComponentBuilder newLogger(String name, boolean includeLocation);

    /**
     * Returns a builder for creating Loggers.
     * @param name The name of the Logger.
     * @param level The logging Level to be assigned to the Logger.
     * @return A new LoggerComponentBuilder.
     */
    LoggerComponentBuilder newLogger(String name, Level level);

    /**
     * Returns a builder for creating Loggers.
     * @param name The name of the Logger.
     * @param level The logging Level to be assigned to the Logger.
     * @param includeLocation If true include location information.
     * @return A new LoggerComponentBuilder.
     */
    LoggerComponentBuilder newLogger(String name, Level level, boolean includeLocation);

    /**
     * Returns a builder for creating Loggers.
     * @param name The name of the Logger.
     * @param level The logging Level to be assigned to the Logger.
     * @return A new LoggerComponentBuilder.
     */
    LoggerComponentBuilder newLogger(String name, String level);

    /**
     * Returns a builder for creating Loggers.
     * @param name The name of the Logger.
     * @param level The logging Level to be assigned to the Logger.
     * @param includeLocation If true include location information.
     * @return A new LoggerComponentBuilder.
     */
    LoggerComponentBuilder newLogger(String name, String level, boolean includeLocation);

    /**
     * Returns a builder for creating the root Logger.
     * @return A new RootLoggerComponentBuilder.
     */
    RootLoggerComponentBuilder newRootLogger();

    /**
     * Returns a builder for creating the root Logger.
     * @param includeLocation If true include location information.
     * @return A new RootLoggerComponentBuilder.
     */
    RootLoggerComponentBuilder newRootLogger(boolean includeLocation);

    /**
     * Returns a builder for creating the root Logger.
     * @param level The logging Level to be assigned to the root Logger.
     * @return A new RootLoggerComponentBuilder.
     */
    RootLoggerComponentBuilder newRootLogger(Level level);

    /**
     * Returns a builder for creating the root Logger.
     * @param level The logging Level to be assigned to the root Logger.
     * @param includeLocation If true include location information.
     * @return A new RootLoggerComponentBuilder.
     */
    RootLoggerComponentBuilder newRootLogger(Level level, boolean includeLocation);

    /**
     * Returns a builder for creating the root Logger.
     * @param level The logging Level to be assigned to the root Logger.
     *
     * @return A new RootLoggerComponentBuilder.
     */
    RootLoggerComponentBuilder newRootLogger(String level);

    /**
     * Returns a builder for creating the root Logger.
     * @param level The logging Level to be assigned to the root Logger.
     *
     * @return A new RootLoggerComponentBuilder.
     */
    RootLoggerComponentBuilder newRootLogger(String level, boolean includeLocation);

    /**
     * Set the Advertiser Plugin name.
     * @param advertiser The Advertiser Plugin name.
     * @return this builder instance.
     */
    ConfigurationBuilder<T> setAdvertiser(String advertiser);

    /**
     * Sets the name of the configuration.
     * @param name the name of the {@link Configuration}. By default is {@code "Constructed"}.
     * @return this builder instance.
     */
    ConfigurationBuilder<T> setConfigurationName(String name);

    /**
     * Sets the configuration source, if one exists.
     * @param configurationSource the ConfigurationSource.
     * @return this builder instance.
     */
    ConfigurationBuilder<T> setConfigurationSource(ConfigurationSource configurationSource);

    /**
     * Sets the interval at which the configuration file should be checked for changes.
     * @param intervalSeconds The number of seconds that should pass between checks of the configuration file.
     * @return this builder instance.
     */
    ConfigurationBuilder<T> setMonitorInterval(String intervalSeconds);

    /**
     * Sets the list of packages to search for plugins.
     * @param packages The comma separated list of packages.
     * @return this builder instance.
     */
    ConfigurationBuilder<T> setPackages(String packages);

    /**
     * Sets whether the shutdown hook should be disabled.
     * @param flag "disable" will prevent the shutdown hook from being set.
     * @return this builder instance.
     */
    ConfigurationBuilder<T> setShutdownHook(String flag);

    /**
     * How long appenders and background tasks will get to shutdown when the JVM shuts down.
     * Default is zero which mean that each appender uses its default timeout, and don't wait for background
     * tasks. Not all appenders will honor this, it is a hint and not an absolute guarantee that the shutdown
     * procedure will not take longer. Setting this too low increase the risk of losing outstanding log events
     * not yet written to the final destination. (Not used if {@link #setShutdownHook(String)} is set to "disable".)
     * @return this builder instance.
     *
     * @see LoggerContext#stop(long, TimeUnit)
     */
    ConfigurationBuilder<T> setShutdownTimeout(long timeout, TimeUnit timeUnit);

    /**
     * Sets the level of the StatusLogger.
     * @param level The logging level.
     * @return this builder instance.
     */
    ConfigurationBuilder<T> setStatusLevel(Level level);


    /**
     * Sets whether the logging should include constructing Plugins.
     * @param verbosity "disable" will hide messages from plugin construction.
     * @return this builder instance.
     */
    ConfigurationBuilder<T> setVerbosity(String verbosity);

    /**
     * Specifies the destination for StatusLogger events. This can be {@code out} (default) for using
     * {@link System#out standard out}, {@code err} for using {@link System#err standard error}, or a file URI to
     * which log events will be written. If the provided URI is invalid, then the default destination of standard
     * out will be used.
     *
     * @param destination where status log messages should be output.
     * @return this builder instance.
     */
    ConfigurationBuilder<T> setDestination(String destination);

    /**
     * Sets the logger context.
     * @param loggerContext the logger context.
     */
    void setLoggerContext(LoggerContext loggerContext);

    /**
     * Add the properties for the root node.
     * @param key The property key.
     * @param value The property value.
     * @return this builder instance.
     */
    ConfigurationBuilder<T> addRootProperty(String key, String value);

    /**
     * Build the configuration and optionally initialize it.
     * @param initialize true if the configuration should be initialized, false otherwise. Generally, Configurations
     *                   should not be initialized when they are constructed.
     * @return The constructed Configuration.
     */
    T build(boolean initialize);

    /**
     * Constructs an XML configuration from this builder.
     *
     * @param output  OutputStream to write to, will not be closed
     *
     * @since 2.7
     */
    void writeXmlConfiguration(OutputStream output) throws IOException;

    /**
     * Constructs an XML configuration from this builder.
     *
     * @return  XML configuration
     *
     * @since 2.7
     */
    String toXmlConfiguration();
}

⏎ org/apache/logging/log4j/core/config/builder/api/ConfigurationBuilder.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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