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/util/Builder.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.util;

/**
 * A type of builder that can be used to configure and create a instances using a Java DSL instead of
 * through a configuration file. These builders are primarily useful for internal code and unit tests, but they can
 * technically be used as a verbose alternative to configuration files.
 *
 * <p>
 *     When creating <em>plugin</em> builders, it is customary to create the builder class as a public static inner class
 *     called {@code Builder}. For instance, the builder class for
 *     {@link org.apache.logging.log4j.core.layout.PatternLayout PatternLayout} would be
 *     {@code PatternLayout.Builder}.
 * </p>
 *
 * @param <T> This builder creates instances of this class.
 */
public interface Builder<T> {

    /**
     * Builds the object after all configuration has been set. This will use default values for any
     * unspecified attributes for the object.
     *
     * @return the configured instance.
     * @throws org.apache.logging.log4j.core.config.ConfigurationException if there was an error building the
     * object.
     */
    T build();
}

⏎ org/apache/logging/log4j/core/util/Builder.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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