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/AbstractLifeCycle.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;

import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;

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

/**
 * A life cycle to be extended.
 * <p>
 * Wraps a {@link LifeCycle.State}.
 * </p>
 */
public class AbstractLifeCycle implements LifeCycle2 {

    public static final int DEFAULT_STOP_TIMEOUT = 0;
    public static final TimeUnit DEFAULT_STOP_TIMEUNIT = TimeUnit.MILLISECONDS;

    /**
     * Allow subclasses access to the status logger without creating another instance.
     */
    protected static final org.apache.logging.log4j.Logger LOGGER = StatusLogger.getLogger();

    /**
     * Gets the status logger.
     *
     * @return the status logger.
     */
    protected static org.apache.logging.log4j.Logger getStatusLogger() {
        return LOGGER;
    }

    private volatile LifeCycle.State state = LifeCycle.State.INITIALIZED;

    protected boolean equalsImpl(final Object obj) {
        if (this == obj) {
            return true;
        }
        if (obj == null) {
            return false;
        }
        if (getClass() != obj.getClass()) {
            return false;
        }
        final LifeCycle other = (LifeCycle) obj;
        if (state != other.getState()) {
            return false;
        }
        return true;
    }

    @Override
    public LifeCycle.State getState() {
        return this.state;
    }

    protected int hashCodeImpl() {
        final int prime = 31;
        int result = 1;
        result = prime * result + ((state == null) ? 0 : state.hashCode());
        return result;
    }

    public boolean isInitialized() {
        return this.state == LifeCycle.State.INITIALIZED;
    }

    @Override
    public boolean isStarted() {
        return this.state == LifeCycle.State.STARTED;
    }

    public boolean isStarting() {
        return this.state == LifeCycle.State.STARTING;
    }

    @Override
    public boolean isStopped() {
        return this.state == LifeCycle.State.STOPPED;
    }

    public boolean isStopping() {
        return this.state == LifeCycle.State.STOPPING;
    }

    protected void setStarted() {
        this.setState(LifeCycle.State.STARTED);
    }

    protected void setStarting() {
        this.setState(LifeCycle.State.STARTING);
    }

    protected void setState(final LifeCycle.State newState) {
        this.state = newState;
        // Need a better string than this.toString() for the message
        // LOGGER.trace("{} {}", this.state, this);
    }

    protected void setStopped() {
        this.setState(LifeCycle.State.STOPPED);
    }

    protected void setStopping() {
        this.setState(LifeCycle.State.STOPPING);
    }

    @Override
    public void initialize() {
        this.state = State.INITIALIZED;
    }

    @Override
    public void start() {
        this.setStarted();
    }

    @Override
    public void stop() {
        stop(DEFAULT_STOP_TIMEOUT, DEFAULT_STOP_TIMEUNIT);
    }

    protected boolean stop(final Future<?> future) {
        boolean stopped = true;
        if (future != null) {
            if (future.isCancelled() || future.isDone()) {
                return true;
            }
            stopped = future.cancel(true);
        }
        return stopped;
    }

    @Override
    public boolean stop(final long timeout, final TimeUnit timeUnit) {
        this.state = LifeCycle.State.STOPPED;
        return true;
    }

}

⏎ org/apache/logging/log4j/core/AbstractLifeCycle.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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