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/nosql/NoSqlProvider.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.nosql;

/**
 * Implementations of this class are plugins for configuring the {@link NoSqlAppender} with the proper provider
 * (MongoDB, etc.).
 *
 * @param <C> Specifies which implementation of {@link NoSqlConnection} this provider provides.
 */
public interface NoSqlProvider<C extends NoSqlConnection<?, ? extends NoSqlObject<?>>> {

    /**
     * Obtains a connection from this provider. The concept of a connection in this case is not strictly an active
     * duplex UDP or TCP connection to the underlying database. It can be thought of more as a gateway, a path for
     * inserting objects that may use a persistent connection or may use HTTP web service calls, etc.
     * <p>
     * Where applicable, this method should return a connection from the connection pool as opposed to opening a
     * brand new connection every time.
     * </p>
     *
     * @return a connection that can be used to create and persist objects to this database.
     * @see NoSqlConnection
     */
    C getConnection();

    /**
     * All implementations must override {@link Object#toString()} to provide information about the provider
     * configuration (obscuring passwords with one-way hashes).
     *
     * @return the string representation of this NoSQL provider.
     */
    @Override
    String toString();
}

⏎ org/apache/logging/log4j/core/appender/nosql/NoSqlProvider.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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