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/jmx/StatusLoggerAdmin.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.jmx;

import java.io.IOException;
import java.util.List;
import java.util.concurrent.Executor;
import java.util.concurrent.atomic.AtomicLong;

import javax.management.MBeanNotificationInfo;
import javax.management.Notification;
import javax.management.NotificationBroadcasterSupport;
import javax.management.ObjectName;

import org.apache.logging.log4j.Level;
import org.apache.logging.log4j.status.StatusData;
import org.apache.logging.log4j.status.StatusListener;
import org.apache.logging.log4j.status.StatusLogger;

/**
 * Implementation of the {@code StatusLoggerAdminMBean} interface.
 */
public class StatusLoggerAdmin extends NotificationBroadcasterSupport implements StatusListener, StatusLoggerAdminMBean {

    private final AtomicLong sequenceNo = new AtomicLong();
    private final ObjectName objectName;
    private final String contextName;
    private Level level = Level.WARN;

    /**
     * Constructs a new {@code StatusLoggerAdmin} with the {@code Executor} to
     * be used for sending {@code Notification}s asynchronously to listeners.
     *
     * @param contextName name of the LoggerContext under which to register this
     *            StatusLoggerAdmin. Note that the StatusLogger may be
     *            registered multiple times, once for each LoggerContext. In web
     *            containers, each web application has its own LoggerContext and
     *            by associating the StatusLogger with the LoggerContext, all
     *            associated MBeans can be unloaded when the web application is
     *            undeployed.
     * @param executor used to send notifications asynchronously
     */
    public StatusLoggerAdmin(final String contextName, final Executor executor) {
        super(executor, createNotificationInfo());
        this.contextName = contextName;
        try {
            final String mbeanName = String.format(PATTERN, Server.escape(contextName));
            objectName = new ObjectName(mbeanName);
        } catch (final Exception e) {
            throw new IllegalStateException(e);
        }
        removeListeners(contextName);
        StatusLogger.getLogger().registerListener(this);
    }

    /**
     * Add listener to StatusLogger for this context, or replace it if it already exists.
     *
     * @param ctxName
     */
    private void removeListeners(final String ctxName) {
        final StatusLogger logger = StatusLogger.getLogger();
        final Iterable<StatusListener> listeners = logger.getListeners();
        // Remove any StatusLoggerAdmin listeners already registered for this context
        for (final StatusListener statusListener : listeners) {
            if (statusListener instanceof StatusLoggerAdmin) {
                final StatusLoggerAdmin adminListener = (StatusLoggerAdmin) statusListener;
                if (ctxName != null && ctxName.equals(adminListener.contextName)) {
                    logger.removeListener(adminListener);
                }
            }
        }
    }

    private static MBeanNotificationInfo createNotificationInfo() {
        final String[] notifTypes = new String[] {
                NOTIF_TYPE_DATA,
                NOTIF_TYPE_MESSAGE };
        final String name = Notification.class.getName();
        final String description = "StatusLogger has logged an event";
        return new MBeanNotificationInfo(notifTypes, name, description);
    }

    @Override
    public String[] getStatusDataHistory() {
        final List<StatusData> data = getStatusData();
        final String[] result = new String[data.size()];
        for (int i = 0; i < result.length; i++) {
            result[i] = data.get(i).getFormattedStatus();
        }
        return result;
    }

    @Override
    public List<StatusData> getStatusData() {
        return StatusLogger.getLogger().getStatusData();
    }

    @Override
    public String getLevel() {
        return this.level.name();
    }

    @Override
    public Level getStatusLevel() {
        return this.level;
    }

    @Override
    public void setLevel(final String level) {
        this.level = Level.toLevel(level, Level.ERROR);
    }

    @Override
    public String getContextName() {
        return contextName;
    }

    /*
     * (non-Javadoc)
     *
     * @see
     * org.apache.logging.log4j.status.StatusListener#log(org.apache.logging
     * .log4j.status.StatusData)
     */
    @Override
    public void log(final StatusData data) {
        final Notification notifMsg = new Notification(NOTIF_TYPE_MESSAGE, getObjectName(), nextSeqNo(), nowMillis(),
                data.getFormattedStatus());
        sendNotification(notifMsg);

        final Notification notifData = new Notification(NOTIF_TYPE_DATA, getObjectName(), nextSeqNo(), nowMillis());
        notifData.setUserData(data);
        sendNotification(notifData);
    }

    /**
     * Returns the {@code ObjectName} of this mbean.
     *
     * @return the {@code ObjectName}
     * @see StatusLoggerAdminMBean#PATTERN
     */
    @Override
    public ObjectName getObjectName() {
        return objectName;
    }

    private long nextSeqNo() {
        return sequenceNo.getAndIncrement();
    }

    private long nowMillis() {
        return System.currentTimeMillis();
    }

    @Override
    public void close() throws IOException {
        // nothing to close here
    }
}

⏎ org/apache/logging/log4j/core/jmx/StatusLoggerAdmin.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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