SLF4J API is a simple API that allows to plug in any desired logging library at deployment time.

Here is the source code for SLF4J API 2.0.4. You can download its pre-compiled version slf4j-api-2.0.4.jar at SLF4J Download Website.

⏎ org/slf4j/LoggerFactoryFriend.java

/**
 * Copyright (c) 2004-2021 QOS.ch
 * All rights reserved.
 *
 * Permission is hereby granted, free  of charge, to any person obtaining
 * a  copy  of this  software  and  associated  documentation files  (the
 * "Software"), to  deal in  the Software without  restriction, including
 * without limitation  the rights to  use, copy, modify,  merge, publish,
 * distribute,  sublicense, and/or sell  copies of  the Software,  and to
 * permit persons to whom the Software  is furnished to do so, subject to
 * the following conditions:
 *
 * The  above  copyright  notice  and  this permission  notice  shall  be
 * included in all copies or substantial portions of the Software.
 *
 * THE  SOFTWARE IS  PROVIDED  "AS  IS", WITHOUT  WARRANTY  OF ANY  KIND,
 * EXPRESS OR  IMPLIED, INCLUDING  BUT NOT LIMITED  TO THE  WARRANTIES OF
 * MERCHANTABILITY,    FITNESS    FOR    A   PARTICULAR    PURPOSE    AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 * OF CONTRACT, TORT OR OTHERWISE,  ARISING FROM, OUT OF OR IN CONNECTION
 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 */
package org.slf4j;

/**
 * All methods in this class are reserved for internal use, for testing purposes.
 * 
 * <p>They can be modified, renamed or removed at any time without notice.
 * 
 * <p>You are strongly discouraged calling any of the methods of this class.
 *
 * @since 1.8.0
 *
 *  @author Ceki G&uuml;lc&uuml;
 */
public class LoggerFactoryFriend {

    /*
     * Force LoggerFactory to consider itself uninitialized.
     */
    static public void reset() {
        LoggerFactory.reset();
    }

    /**
     * Set LoggerFactory.DETECT_LOGGER_NAME_MISMATCH variable.
     * 
     * @param enabled a boolean
     */
    public static void setDetectLoggerNameMismatch(boolean enabled) {
        LoggerFactory.DETECT_LOGGER_NAME_MISMATCH = enabled;
    }
}

⏎ org/slf4j/LoggerFactoryFriend.java

Or download all of them as a single archive file:

File name: slf4j-api-2.0.4-sources.jar
File size: 70304 bytes
Release date: 2022-11-17
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