001/*
002 * Copyright 2002-2018 the original author or authors.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *      https://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017package org.springframework.messaging.tcp.reactor;
018
019import java.nio.ByteBuffer;
020import java.util.Collection;
021import java.util.List;
022
023import io.netty.buffer.ByteBuf;
024
025import org.springframework.messaging.Message;
026
027/**
028 * Convenient base class for {@link ReactorNettyCodec} implementations that need
029 * to work with NIO {@link ByteBuffer ByteBuffers}.
030 *
031 * @author Rossen Stoyanchev
032 * @since 5.0
033 * @param <P> the message payload type
034 */
035public abstract class AbstractNioBufferReactorNettyCodec<P> implements ReactorNettyCodec<P> {
036
037        @Override
038        public Collection<Message<P>> decode(ByteBuf inputBuffer) {
039                ByteBuffer nioBuffer = inputBuffer.nioBuffer();
040                int start = nioBuffer.position();
041                List<Message<P>> messages = decodeInternal(nioBuffer);
042                inputBuffer.skipBytes(nioBuffer.position() - start);
043                return messages;
044        }
045
046        @Override
047        public void encode(Message<P> message, ByteBuf outputBuffer) {
048                outputBuffer.writeBytes(encodeInternal(message));
049        }
050
051
052        protected abstract List<Message<P>> decodeInternal(ByteBuffer nioBuffer);
053
054        protected abstract ByteBuffer encodeInternal(Message<P> message);
055
056}