Apache Log4j API provides the interface that applications should code to and provides the adapter components required for implementers to create a logging implementation. Apache Log4j API is a required module to use Apache Log4j.

Bytecode (Java 8) for Apache Log4j API is provided in a separate JAR file like log4j-api-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 API 2.14.1 below.

⏎ org/apache/logging/log4j/LogBuilder.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;

import org.apache.logging.log4j.message.Message;
import org.apache.logging.log4j.util.Supplier;


/**
 * Interface for constructing log events before logging them. Instances of LogBuilders should only be created
 * by calling one of the Logger methods that return a LogBuilder.
 */
public interface LogBuilder {

    public static final LogBuilder NOOP = new LogBuilder() {};

    /**
     * Includes a Marker in the log event. Interface default method does nothing.
     * @param marker The Marker to log.
     * @return The LogBuilder.
     */
    default LogBuilder withMarker(Marker marker) {
        return this;
    }

    /**
     * Includes a Throwable in the log event. Interface default method does nothing.
     * @param throwable The Throwable to log.
     * @return the LogBuilder.
     */
    default LogBuilder withThrowable(Throwable throwable) {
        return this;
    }

    /**
     * An implementation will calculate the caller's stack frame and include it in the log event.
     * Interface default method does nothing.
     * @return The LogBuilder.
     */
    default LogBuilder withLocation() {
        return this;
    }

    /**
     * Adds the specified stack trace element to the log event. Interface default method does nothing.
     * @param location The stack trace element to include in the log event.
     * @return The LogBuilder.
     */
    default LogBuilder withLocation(StackTraceElement location) {
        return this;
    }

    /**
     * Causes all the data collected to be logged along with the message. Interface default method does nothing.
     * @param message The message to log.
     */
    default void log(CharSequence message) {
    }

    /**
     * Causes all the data collected to be logged along with the message. Interface default method does nothing.
     * @param message The message to log.
     */
    default void log(String message) {
    }

    /**
     * Logs a message with parameters. Interface default method does nothing.
     *
     * @param message the message to log; the format depends on the message factory.
     * @param params parameters to the message.
     *
     * @see org.apache.logging.log4j.util.Unbox
     */
    default void log(String message, Object... params) {
    }

    /**
     * Causes all the data collected to be logged along with the message and parameters.
     * Interface default method does nothing.
     * @param message The message.
     * @param params Parameters to the message.
     */
    default void log(String message, Supplier<?>... params) {
    }

    /**
     * Causes all the data collected to be logged along with the message. Interface default method does nothing.
     * @param message The message to log.
     */
    default void log(Message message) {
    }

    /**
     * Causes all the data collected to be logged along with the message. Interface default method does nothing.
     * @param messageSupplier The supplier of the message to log.
     */
    default void log(Supplier<Message> messageSupplier) {
    }

    /**
     * Causes all the data collected to be logged along with the message. Interface default method does nothing.
     * @param message The message to log.
     */
    default void log(Object message) {
    }

    /**
     * Logs a message with parameters. Interface default method does nothing.
     *
     * @param message the message to log; the format depends on the message factory.
     * @param p0 parameter to the message.
     *
     * @see org.apache.logging.log4j.util.Unbox
     */
    default void log(String message, Object p0) {
    }

    /**
     * Logs a message with parameters. Interface default method does nothing.
     *
     * @param message the message to log; the format depends on the message factory.
     * @param p0 parameter to the message.
     * @param p1 parameter to the message.
     *
     * @see org.apache.logging.log4j.util.Unbox
     */
    default void log(String message, Object p0, Object p1) {
    }

    /**
     * Logs a message with parameters. Interface default method does nothing.
     *
     * @param message the message to log; the format depends on the message factory.
     * @param p0 parameter to the message.
     * @param p1 parameter to the message.
     * @param p2 parameter to the message.
     *
     * @see org.apache.logging.log4j.util.Unbox
     */
    default void log(String message, Object p0, Object p1, Object p2) {
    }

    /**
     * Logs a message with parameters. Interface default method does nothing.
     *
     * @param message the message to log; the format depends on the message factory.
     * @param p0 parameter to the message.
     * @param p1 parameter to the message.
     * @param p2 parameter to the message.
     * @param p3 parameter to the message.
     *
     * @see org.apache.logging.log4j.util.Unbox
     */
    default void log(String message, Object p0, Object p1, Object p2, Object p3) {
    }

    /**
     * Logs a message with parameters. Interface default method does nothing.
     *
     * @param message the message to log; the format depends on the message factory.
     * @param p0 parameter to the message.
     * @param p1 parameter to the message.
     * @param p2 parameter to the message.
     * @param p3 parameter to the message.
     * @param p4 parameter to the message.
     *
     * @see org.apache.logging.log4j.util.Unbox
     */
    default void log(String message, Object p0, Object p1, Object p2, Object p3, Object p4) {
    }

    /**
     * Logs a message with parameters. Interface default method does nothing.
     *
     * @param message the message to log; the format depends on the message factory.
     * @param p0 parameter to the message.
     * @param p1 parameter to the message.
     * @param p2 parameter to the message.
     * @param p3 parameter to the message.
     * @param p4 parameter to the message.
     * @param p5 parameter to the message.
     *
     * @see org.apache.logging.log4j.util.Unbox
     */
    default void log(String message, Object p0, Object p1, Object p2, Object p3, Object p4, Object p5) {
    }

    /**
     * Logs a message with parameters.
     *
     * @param message the message to log; the format depends on the message factory.
     * @param p0 parameter to the message.
     * @param p1 parameter to the message.
     * @param p2 parameter to the message.
     * @param p3 parameter to the message.
     * @param p4 parameter to the message.
     * @param p5 parameter to the message.
     * @param p6 parameter to the message.
     *
     * @see org.apache.logging.log4j.util.Unbox
     */
    default void log(String message, Object p0, Object p1, Object p2, Object p3, Object p4, Object p5, Object p6) {
    }

    /**
     * Logs a message with parameters. Interface default method does nothing.
     *
     * @param message the message to log; the format depends on the message factory.
     * @param p0 parameter to the message.
     * @param p1 parameter to the message.
     * @param p2 parameter to the message.
     * @param p3 parameter to the message.
     * @param p4 parameter to the message.
     * @param p5 parameter to the message.
     * @param p6 parameter to the message.
     * @param p7 parameter to the message.
     *
     * @see org.apache.logging.log4j.util.Unbox
     */
    default void log(String message, Object p0, Object p1, Object p2, Object p3, Object p4, Object p5, Object p6,
            Object p7) {
    }

    /**
     * Logs a message with parameters. Interface default method does nothing.
     *
     * @param message the message to log; the format depends on the message factory.
     * @param p0 parameter to the message.
     * @param p1 parameter to the message.
     * @param p2 parameter to the message.
     * @param p3 parameter to the message.
     * @param p4 parameter to the message.
     * @param p5 parameter to the message.
     * @param p6 parameter to the message.
     * @param p7 parameter to the message.
     * @param p8 parameter to the message.
     *
     * @see org.apache.logging.log4j.util.Unbox
     */
    default void log(String message, Object p0, Object p1, Object p2, Object p3, Object p4, Object p5, Object p6,
            Object p7, Object p8) {
    }

    /**
     * Logs a message with parameters. Interface default method does nothing.
     *
     * @param message the message to log; the format depends on the message factory.
     * @param p0 parameter to the message.
     * @param p1 parameter to the message.
     * @param p2 parameter to the message.
     * @param p3 parameter to the message.
     * @param p4 parameter to the message.
     * @param p5 parameter to the message.
     * @param p6 parameter to the message.
     * @param p7 parameter to the message.
     * @param p8 parameter to the message.
     * @param p9 parameter to the message.
     *
     * @see org.apache.logging.log4j.util.Unbox
     */
    default void log(String message, Object p0, Object p1, Object p2, Object p3, Object p4, Object p5, Object p6,
            Object p7, Object p8, Object p9) {
    }

    /**
     * Causes all the data collected to be logged. Default implementatoin does nothing.
     */
    default void log() {
    }
}

⏎ org/apache/logging/log4j/LogBuilder.java

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File name: log4j-api-2.14.1-sources.jar
File size: 264773 bytes
Release date: 2021-03-06
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