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/appender/routing/Route.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.appender.routing;

import org.apache.logging.log4j.Logger;
import org.apache.logging.log4j.core.Core;
import org.apache.logging.log4j.core.config.Node;
import org.apache.logging.log4j.core.config.plugins.Plugin;
import org.apache.logging.log4j.core.config.plugins.PluginAttribute;
import org.apache.logging.log4j.core.config.plugins.PluginFactory;
import org.apache.logging.log4j.core.config.plugins.PluginNode;
import org.apache.logging.log4j.status.StatusLogger;

/**
 * A Route to an appender.
 */
@Plugin(name = "Route", category = Core.CATEGORY_NAME, printObject = true, deferChildren = true)
public final class Route {
    private static final Logger LOGGER = StatusLogger.getLogger();

    private final Node node;
    private final String appenderRef;
    private final String key;

    private Route(final Node node, final String appenderRef, final String key) {
        this.node = node;
        this.appenderRef = appenderRef;
        this.key = key;
    }

    /**
     * Returns the Dynamic Appender Node.
     * @return The Node.
     */
    public Node getNode() {
        return node;
    }

    /**
     * Returns the appender reference.
     * @return The Appender reference.
     */
    public String getAppenderRef() {
        return appenderRef;
    }

    /**
     * Returns the key for this Route.
     * @return the key for this Route.
     */
    public String getKey() {
        return key;
    }

    @Override
    public String toString() {
        final StringBuilder sb = new StringBuilder("Route(");
        sb.append("type=");
        if (appenderRef != null) {
            sb.append("static Reference=").append(appenderRef);
        } else if (node != null) {
            sb.append("dynamic - type=").append(node.getName());
        } else {
            sb.append("invalid Route");
        }
        if (key != null) {
            sb.append(" key='").append(key).append('\'');
        } else {
            sb.append(" default");
        }
        sb.append(')');
        return sb.toString();
    }

    /**
     * Create the Route.
     * @param appenderRef The Appender reference.
     * @param key The key.
     * @param node The Node.
     * @return A Route.
     */
    @PluginFactory
    public static Route createRoute(
            @PluginAttribute("ref") final String appenderRef,
            @PluginAttribute("key") final String key,
            @PluginNode final Node node) {
        if (node != null && node.hasChildren()) {
            if (appenderRef != null) {
                LOGGER.error("A route cannot be configured with an appender reference and an appender definition");
                return null;
            }
        } else if (appenderRef == null) {
            LOGGER.error("A route must specify an appender reference or an appender definition");
            return null;
        }
        return new Route(node, appenderRef, key);
    }
}

⏎ org/apache/logging/log4j/core/appender/routing/Route.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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