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/pattern/AbstractPatternConverter.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.pattern;

import org.apache.logging.log4j.Logger;
import org.apache.logging.log4j.status.StatusLogger;


/**
 * AbstractPatternConverter is an abstract class that provides the formatting functionality that derived classes need.
 * <p>
 * Conversion specifiers in a conversion patterns are parsed to individual PatternConverters. Each of which is
 * responsible for converting an object in a converter specific manner.
 * </p>
 */
public abstract class AbstractPatternConverter implements PatternConverter {
    /**
     * Allow subclasses access to the status logger.
     */
    protected static final Logger LOGGER = StatusLogger.getLogger();

    /**
     * Converter name.
     */
    private final String name;

    /**
     * Converter style name.
     */
    private final String style;

    /**
     * Create a new pattern converter.
     *
     * @param name  name for pattern converter.
     * @param style CSS style for formatted output.
     */
    protected AbstractPatternConverter(final String name, final String style) {
        this.name = name;
        this.style = style;
    }

    /**
     * This method returns the name of the conversion pattern.
     * <p>
     * The name can be useful to certain Layouts such as HtmlLayout.
     * </p>
     *
     * @return the name of the conversion pattern
     */
    @Override
    public final String getName() {
        return name;
    }

    /**
     * This method returns the CSS style class that should be applied to the LoggingEvent passed as parameter, which can
     * be null.
     * <p>
     * This information is currently used only by HtmlLayout.
     * </p>
     *
     * @param e
     *        null values are accepted
     * @return the name of the conversion pattern
     */
    @Override
    public String getStyleClass(final Object e) {
        return style;
    }
}

⏎ org/apache/logging/log4j/core/pattern/AbstractPatternConverter.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
Download 

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