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/layout/ByteBufferDestination.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.layout;

import java.nio.ByteBuffer;

import org.apache.logging.log4j.core.appender.OutputStreamManager;

/**
 * ByteBufferDestination is the destination that {@link Encoder}s write binary data to. It encapsulates a
 * {@code ByteBuffer} and a {@code drain()} method the producer can call when the {@code ByteBuffer} is full.
 * <p>
 * This interface allows a producer to write arbitrary amounts of data to a destination.
 * </p>
 * @since 2.6
 */
public interface ByteBufferDestination {
    /**
     * Returns the buffer to write to.
     *
     * @return the buffer to write to
     */
    ByteBuffer getByteBuffer();

    /**
     * Consumes the buffer content and returns a buffer with more {@linkplain ByteBuffer#remaining() available} space
     * (which may or may not be the same instance).
     * <p>
     * Called by the producer when buffer becomes too full to write to.
     *
     * @param buf the buffer to drain
     * @return a buffer with more available space (which may or may not be the same instance)
     */
    ByteBuffer drain(ByteBuffer buf);

    /**
     * Writes the given data to this ByteBufferDestination entirely. Call of this method should *not* be protected
     * with synchronized on this ByteBufferDestination instance. ByteBufferDestination implementations should
     * synchronize themselves inside this method, if needed.
     *
     * @since 2.9 (see LOG4J2-1874)
     */
    void writeBytes(ByteBuffer data);

    /**
     * Writes the given data to this ByteBufferDestination. Call of this method should *not* be protected with
     * synchronized on this ByteBufferDestination instance. ByteBufferDestination implementations should
     * synchronize themselves inside this method, if needed.
     * <p>
     * This method should behave identically to {@code writeBytes(ByteBuffer.wrap(data, offset, length)}.
     * It is provided to allow callers not to generate extra garbage.
     * <p>
     * This method is called writeBytes() to avoid clashing with {@link OutputStreamManager#write(byte[], int, int)},
     * which might be overridden in user-defined subclasses as protected, hence adding it to interface and requiring
     * the method to be public breaks source compatibility.
     *
     * @since 2.9 (see LOG4J2-1874)
     */
    void writeBytes(byte[] data, int offset, int length);
}

⏎ org/apache/logging/log4j/core/layout/ByteBufferDestination.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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