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/AbstractLogEvent.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.Collections;
import java.util.Map;

import org.apache.logging.log4j.Level;
import org.apache.logging.log4j.Marker;
import org.apache.logging.log4j.ThreadContext;
import org.apache.logging.log4j.ThreadContext.ContextStack;
import org.apache.logging.log4j.core.impl.ThrowableProxy;
import org.apache.logging.log4j.core.time.Instant;
import org.apache.logging.log4j.core.time.MutableInstant;
import org.apache.logging.log4j.message.Message;
import org.apache.logging.log4j.util.ReadOnlyStringMap;


/**
 * An abstract log event implementation with default values for all methods. The setters are no-ops.
 */
public abstract class AbstractLogEvent implements LogEvent {

    private static final long serialVersionUID = 1L;

    private volatile MutableInstant instant;

    /**
     * Subclasses should implement this method to provide an immutable version.
     */
    @Override
    public LogEvent toImmutable() {
        return this;
    }

    @Override
    public ReadOnlyStringMap getContextData() {
        return null;
    }

    /**
     * Returns {@link Collections#emptyMap()}.
     */
    @Override
    public Map<String, String> getContextMap() {
        return Collections.emptyMap();
    }

    @Override
    public ContextStack getContextStack() {
        return ThreadContext.EMPTY_STACK;
    }

    @Override
    public Level getLevel() {
        return null;
    }

    @Override
    public String getLoggerFqcn() {
        return null;
    }

    @Override
    public String getLoggerName() {
        return null;
    }

    @Override
    public Marker getMarker() {
        return null;
    }

    @Override
    public Message getMessage() {
        return null;
    }

    @Override
    public StackTraceElement getSource() {
        return null;
    }

    @Override
    public long getThreadId() {
        return 0;
    }

    @Override
    public String getThreadName() {
        return null;
    }

    @Override
    public int getThreadPriority() {
        return 0;
    }

    @Override
    public Throwable getThrown() {
        return null;
    }

    @Override
    public ThrowableProxy getThrownProxy() {
        return null;
    }

    @Override
    public long getTimeMillis() {
        return 0;
    }

    @Override
    public Instant getInstant() {
        return getMutableInstant();
    }

    protected final MutableInstant getMutableInstant() {
        if (instant == null) {
            instant = new MutableInstant();
        }
        return instant;
    }

    @Override
    public boolean isEndOfBatch() {
        return false;
    }

    @Override
    public boolean isIncludeLocation() {
        return false;
    }

    @Override
    public void setEndOfBatch(final boolean endOfBatch) {
        // do nothing
    }

    @Override
    public void setIncludeLocation(final boolean locationRequired) {
        // do nothing
    }

    @Override
    public long getNanoTime() {
        return 0;
    }
}

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