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/util/AbstractWatcher.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.util;

import java.util.List;

import org.apache.logging.log4j.core.config.Configuration;
import org.apache.logging.log4j.core.config.ConfigurationListener;
import org.apache.logging.log4j.core.config.Reconfigurable;

/**
 * Watcher for configuration files. Causes a reconfiguration when a file changes.
 */
public abstract class AbstractWatcher implements Watcher {

    private final Reconfigurable reconfigurable;
    private final List<ConfigurationListener> configurationListeners;
    private final Log4jThreadFactory threadFactory;
    private final Configuration configuration;
    private Source source;

    public AbstractWatcher(final Configuration configuration, final Reconfigurable reconfigurable,
            final List<ConfigurationListener> configurationListeners) {
        this.configuration = configuration;
        this.reconfigurable = reconfigurable;
        this.configurationListeners = configurationListeners;
        this.threadFactory = configurationListeners != null ?
            Log4jThreadFactory.createDaemonThreadFactory("ConfiguratonFileWatcher") : null;
    }

    @Override
    public List<ConfigurationListener> getListeners() {
        return configurationListeners;
    }

    @Override
    public void modified() {
        for (final ConfigurationListener configurationListener : configurationListeners) {
            final Thread thread = threadFactory.newThread(new ReconfigurationRunnable(configurationListener, reconfigurable));
            thread.start();
        }
    }

    public Configuration getConfiguration() {
        return configuration;
    }

    @Override
    public abstract long getLastModified();

    @Override
    public abstract boolean isModified();

    @Override
    public void watching(Source source) {
        this.source = source;
    }

    @Override
    public Source getSource() {
        return source;
    }

    /**
     * Helper class for triggering a reconfiguration in a background thread.
     */
    public static class ReconfigurationRunnable implements Runnable {

        private final ConfigurationListener configurationListener;
        private final Reconfigurable reconfigurable;

        public ReconfigurationRunnable(final ConfigurationListener configurationListener, final Reconfigurable reconfigurable) {
            this.configurationListener = configurationListener;
            this.reconfigurable = reconfigurable;
        }

        @Override
        public void run() {
            configurationListener.onChange(reconfigurable);
        }
    }
}

⏎ org/apache/logging/log4j/core/util/AbstractWatcher.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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