org.apache.flink.runtime.io.network.netty.NonBufferResponseDecoder Maven / Gradle / Ivy

Show more of this group Show more artifacts with this name
Show all versions of flink-runtime_2.11 Show documentation
There is a newer version: 1.13.6
/*
 * 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.flink.runtime.io.network.netty;

import org.apache.flink.shaded.netty4.io.netty.buffer.ByteBuf;
import org.apache.flink.shaded.netty4.io.netty.channel.ChannelHandlerContext;

import java.net.ProtocolException;

import static org.apache.flink.runtime.io.network.netty.NettyMessage.BufferResponse;
import static org.apache.flink.runtime.io.network.netty.NettyMessage.ErrorResponse;

/**
 * The decoder for messages other than {@link BufferResponse}.
 */
class NonBufferResponseDecoder extends NettyMessageDecoder {

	/** The initial size of the message header accumulation buffer. */
	private static final int INITIAL_MESSAGE_HEADER_BUFFER_LENGTH = 128;

	/** The accumulation buffer of the message. */
	private ByteBuf messageBuffer;

	@Override
	public void onChannelActive(ChannelHandlerContext ctx) {
		messageBuffer = ctx.alloc().directBuffer(INITIAL_MESSAGE_HEADER_BUFFER_LENGTH);
	}

	@Override
	void onNewMessageReceived(int msgId, int messageLength) {
		super.onNewMessageReceived(msgId, messageLength);
		messageBuffer.clear();
		ensureBufferCapacity();
	}

	@Override
	public DecodingResult onChannelRead(ByteBuf data) throws Exception {
		ByteBuf fullFrameHeaderBuf = ByteBufUtils.accumulate(
			messageBuffer,
			data,
			messageLength,
			messageBuffer.readableBytes());
		if (fullFrameHeaderBuf == null) {
			return DecodingResult.NOT_FINISHED;
		}

		switch (msgId) {
			case ErrorResponse.ID:
				return DecodingResult.fullMessage(ErrorResponse.readFrom(fullFrameHeaderBuf));
			default:
				throw new ProtocolException("Received unknown message from producer: " + msgId);
		}
	}

	/**
	 * Ensures the message header accumulation buffer has enough capacity for
	 * the current message.
	 */
	private void ensureBufferCapacity() {
		if (messageBuffer.capacity() < messageLength) {
			messageBuffer.capacity(messageLength);
		}
	}

	@Override
	public void close() {
		messageBuffer.release();
	}
}