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/time/MutableInstant.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.time;

import org.apache.logging.log4j.core.util.Clock;
import org.apache.logging.log4j.util.PerformanceSensitive;

import java.io.Serializable;

/**
 * An instantaneous point on the time line, used for high-precision log event timestamps.
 * Modeled on <a href="https://docs.oracle.com/javase/9/docs/api/index.html?java/time/class-use/Instant.html">java.time.Instant</a>,
 * except that this version is mutable to prevent allocating temporary objects that need to be garbage-collected later.
 * <p>
 * Instances of this class are <em>not</em> thread-safe and should not be shared between threads.
 * </p>
 *
 * @since 2.11
 */
@PerformanceSensitive("allocation")
public class MutableInstant implements Instant, Serializable {

    private static final int MILLIS_PER_SECOND = 1000;
    private static final int NANOS_PER_MILLI = 1000_000;
    private static final int NANOS_PER_SECOND = MILLIS_PER_SECOND * NANOS_PER_MILLI;

    private long epochSecond;
    private int nanoOfSecond;

    @Override
    public long getEpochSecond() {
        return epochSecond;
    }

    @Override
    public int getNanoOfSecond() {
        return nanoOfSecond;
    }

    @Override
    public long getEpochMillisecond() {
        final int millis = nanoOfSecond / NANOS_PER_MILLI;
        final long epochMillisecond = epochSecond * MILLIS_PER_SECOND + millis;
        return epochMillisecond;
    }

    @Override
    public int getNanoOfMillisecond() {
        final int millis = nanoOfSecond / NANOS_PER_MILLI;
        final int nanoOfMillisecond = nanoOfSecond - (millis * NANOS_PER_MILLI); // cheaper than nanoOfSecond % NANOS_PER_MILLI
        return nanoOfMillisecond;
    }

    public void initFrom(final Instant other) {
        this.epochSecond = other.getEpochSecond();
        this.nanoOfSecond = other.getNanoOfSecond();
    }

    /**
     * Updates the fields of this {@code MutableInstant} from the specified epoch millis.
     * @param epochMilli the number of milliseconds from the Java epoch of 1970-01-01T00:00:00Z
     * @param nanoOfMillisecond the number of nanoseconds, later along the time-line, from the start of the millisecond
     */
    public void initFromEpochMilli(final long epochMilli, final int nanoOfMillisecond) {
        validateNanoOfMillisecond(nanoOfMillisecond);
        this.epochSecond = epochMilli / MILLIS_PER_SECOND;
        this.nanoOfSecond = (int) (epochMilli - (epochSecond * MILLIS_PER_SECOND)) * NANOS_PER_MILLI + nanoOfMillisecond;
    }

    private void validateNanoOfMillisecond(final int nanoOfMillisecond) {
        if (nanoOfMillisecond < 0 || nanoOfMillisecond >= NANOS_PER_MILLI) {
            throw new IllegalArgumentException("Invalid nanoOfMillisecond " + nanoOfMillisecond);
        }
    }

    public void initFrom(final Clock clock) {
        if (clock instanceof PreciseClock) {
            ((PreciseClock) clock).init(this);
        } else {
            initFromEpochMilli(clock.currentTimeMillis(), 0);
        }
    }

    /**
     * Updates the fields of this {@code MutableInstant} from the specified instant components.
     * @param epochSecond the number of seconds from the Java epoch of 1970-01-01T00:00:00Z
     * @param nano the number of nanoseconds, later along the time-line, from the start of the second
     */
    public void initFromEpochSecond(final long epochSecond, final int nano) {
        validateNanoOfSecond(nano);
        this.epochSecond = epochSecond;
        this.nanoOfSecond = nano;
    }

    private void validateNanoOfSecond(final int nano) {
        if (nano < 0 || nano >= NANOS_PER_SECOND) {
            throw new IllegalArgumentException("Invalid nanoOfSecond " + nano);
        }
    }

    /**
     * Updates the elements of the specified {@code long[]} result array from the specified instant components.
     * @param epochSecond (input) the number of seconds from the Java epoch of 1970-01-01T00:00:00Z
     * @param nano (input) the number of nanoseconds, later along the time-line, from the start of the second
     * @param result (output) a two-element array to store the result: the first element is the number of milliseconds
     *               from the Java epoch of 1970-01-01T00:00:00Z,
     *               the second element is the number of nanoseconds, later along the time-line, from the start of the millisecond
     */
    public static void instantToMillisAndNanos(final long epochSecond, final int nano, final long[] result) {
        final int millis = nano / NANOS_PER_MILLI;
        result[0] = epochSecond * MILLIS_PER_SECOND + millis;
        result[1] = nano - (millis * NANOS_PER_MILLI); // cheaper than nanoOfSecond % NANOS_PER_MILLI
    }

    @Override
    public boolean equals(final Object object) {
        if (object == this) {
            return true;
        }
        if (!(object instanceof MutableInstant)) {
            return false;
        }
        final MutableInstant other = (MutableInstant) object;
        return epochSecond == other.epochSecond && nanoOfSecond == other.nanoOfSecond;
    }

    @Override
    public int hashCode() {
        int result = 17;
        result = 31 * result + (int) (epochSecond ^ (epochSecond >>> 32));
        result = 31 * result + nanoOfSecond;
        return result;
    }

    @Override
    public String toString() {
        final StringBuilder sb = new StringBuilder(64);
        formatTo(sb);
        return sb.toString();
    }

    @Override
    public void formatTo(final StringBuilder buffer) {
        buffer.append("MutableInstant[epochSecond=").append(epochSecond).append(", nano=").append(nanoOfSecond).append("]");
    }
}

⏎ org/apache/logging/log4j/core/time/MutableInstant.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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