001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements. See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache license, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License. You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the license for the specific language governing permissions and
015 * limitations under the license.
016 */
017package org.apache.logging.log4j.core.layout;
018
019import java.nio.ByteBuffer;
020
021/**
022 * ByteBufferDestination is the destination that {@link Encoder}s write binary data to. It encapsulates a
023 * {@code ByteBuffer} and a {@code drain()} method the producer can call when the {@code ByteBuffer} is full.
024 * <p>
025 * This interface allows a producer to write arbitrary amounts of data to a destination.
026 * </p>
027 * @since 2.6
028 */
029public interface ByteBufferDestination {
030    /**
031     * Returns the buffer to write to.
032     *
033     * @return the buffer to write to
034     */
035    ByteBuffer getByteBuffer();
036
037    /**
038     * Consumes the buffer content and returns a buffer with more {@linkplain ByteBuffer#remaining() available} space
039     * (which may or may not be the same instance).
040     * <p>
041     * Called by the producer when buffer becomes too full to write to.
042     *
043     * @param buf the buffer to drain
044     * @return a buffer with more available space (which may or may not be the same instance)
045     */
046    ByteBuffer drain(ByteBuffer buf);
047}