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/message/MultiformatMessage.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.message;

/**
 * A Message that can render itself in more than one way. The format string is used by the
 * Message implementation as extra information that it may use to help it to determine how
 * to format itself. For example, MapMessage accepts a format of "XML" to tell it to render
 * the Map as XML instead of its default format of {key1="value1" key2="value2"}.
 */
public interface MultiformatMessage extends Message {

    /**
     * Returns the Message formatted as a String.
     *
     * @param formats An array of Strings that provide extra information about how to format the message.
     * Each MultiformatMessage implementation is free to use the provided formats however they choose.
     *
     * @return The message String.
     */
    String getFormattedMessage(String[] formats);

    /**
     * Returns the supported formats.
     * @return The supported formats.
     */
    String[] getFormats();
}

⏎ org/apache/logging/log4j/message/MultiformatMessage.java

Or download all of them as a single archive file:

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

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