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/impl/BuiltConfiguration.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.impl;

import java.io.IOException;
import java.io.InputStream;
import java.util.Arrays;
import java.util.List;

import org.apache.logging.log4j.core.LoggerContext;
import org.apache.logging.log4j.core.config.AbstractConfiguration;
import org.apache.logging.log4j.core.config.ConfigurationSource;
import org.apache.logging.log4j.core.config.Node;
import org.apache.logging.log4j.core.config.Reconfigurable;
import org.apache.logging.log4j.core.config.builder.api.Component;
import org.apache.logging.log4j.core.config.plugins.util.PluginManager;
import org.apache.logging.log4j.core.config.plugins.util.PluginType;
import org.apache.logging.log4j.core.config.plugins.util.ResolverUtil;
import org.apache.logging.log4j.core.config.status.StatusConfiguration;
import org.apache.logging.log4j.core.util.Patterns;

/**
 * This is the general version of the Configuration created by the Builder. It may be extended to
 * enhance its functionality.
 *
 * @since 2.4
 */
public class BuiltConfiguration extends AbstractConfiguration {
    private static final String[] VERBOSE_CLASSES = new String[] { ResolverUtil.class.getName() };
    private final StatusConfiguration statusConfig;
    protected Component rootComponent;
    private Component loggersComponent;
    private Component appendersComponent;
    private Component filtersComponent;
    private Component propertiesComponent;
    private Component customLevelsComponent;
    private Component scriptsComponent;
    private String contentType = "text";

    public BuiltConfiguration(final LoggerContext loggerContext, final ConfigurationSource source, final Component rootComponent) {
        super(loggerContext, source);
        statusConfig = new StatusConfiguration().withVerboseClasses(VERBOSE_CLASSES).withStatus(getDefaultStatus());
        for (final Component component : rootComponent.getComponents()) {
            switch (component.getPluginType()) {
                case "Scripts": {
                    scriptsComponent = component;
                    break;
                }
                case "Loggers": {
                    loggersComponent = component;
                    break;
                }
                case "Appenders": {
                    appendersComponent = component;
                    break;
                }
                case "Filters": {
                    filtersComponent = component;
                    break;
                }
                case "Properties": {
                    propertiesComponent = component;
                    break;
                }
                case "CustomLevels": {
                    customLevelsComponent = component;
                    break;
                }
            }
        }
        this.rootComponent = rootComponent;
    }

    @Override
    public void setup() {
        final List<Node> children = rootNode.getChildren();
        if (propertiesComponent.getComponents().size() > 0) {
            children.add(convertToNode(rootNode, propertiesComponent));
        }
        if (scriptsComponent.getComponents().size() > 0) {
            children.add(convertToNode(rootNode, scriptsComponent));
        }
        if (customLevelsComponent.getComponents().size() > 0) {
            children.add(convertToNode(rootNode, customLevelsComponent));
        }
        children.add(convertToNode(rootNode, loggersComponent));
        children.add(convertToNode(rootNode, appendersComponent));
        if (filtersComponent.getComponents().size() > 0) {
            if (filtersComponent.getComponents().size() == 1) {
                children.add(convertToNode(rootNode, filtersComponent.getComponents().get(0)));
            } else {
                children.add(convertToNode(rootNode, filtersComponent));
            }
        }
        rootComponent = null;
    }

    public String getContentType() {
        return this.contentType;
    }

    public void setContentType(final String contentType) {
        this.contentType = contentType;
    }

    public void createAdvertiser(final String advertiserString, final ConfigurationSource configSource) {
        byte[] buffer = null;
        try {
            if (configSource != null) {
                final InputStream is = configSource.getInputStream();
                if (is != null) {
                    buffer = toByteArray(is);
                }
            }
        } catch (final IOException ioe) {
            LOGGER.warn("Unable to read configuration source " + configSource.toString());
        }
        super.createAdvertiser(advertiserString, configSource, buffer, contentType);
    }

    public StatusConfiguration getStatusConfiguration() {
        return statusConfig;
    }

    public void setPluginPackages(final String packages) {
        pluginPackages.addAll(Arrays.asList(packages.split(Patterns.COMMA_SEPARATOR)));
    }

    public void setShutdownHook(final String flag) {
        isShutdownHookEnabled = !"disable".equalsIgnoreCase(flag);
    }

    public void setShutdownTimeoutMillis(final long shutdownTimeoutMillis) {
        this.shutdownTimeoutMillis = shutdownTimeoutMillis;
    }

    public void setMonitorInterval(final int intervalSeconds) {
        if (this instanceof Reconfigurable && intervalSeconds > 0) {
            initializeWatchers((Reconfigurable) this, getConfigurationSource(), intervalSeconds);
        }
    }

    @Override
    public PluginManager getPluginManager() {
        return pluginManager;
    }

    protected Node convertToNode(final Node parent, final Component component) {
        final String name = component.getPluginType();
        final PluginType<?> pluginType = pluginManager.getPluginType(name);
        final Node node = new Node(parent, name, pluginType);
        node.getAttributes().putAll(component.getAttributes());
        node.setValue(component.getValue());
        final List<Node> children = node.getChildren();
        for (final Component child : component.getComponents()) {
            children.add(convertToNode(node, child));
        }
        return node;
    }
}

⏎ org/apache/logging/log4j/core/config/builder/impl/BuiltConfiguration.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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