netty5心跳与阻塞性业务消息分发实例

　　继续之前的例子（netty5心跳与业务消息分发实例），我们在NettyClientHandler把业务消息改为阻塞性的：

package com.wlf.netty.nettyclient.handler;

import com.wlf.netty.nettyapi.javabean.Header;
import com.wlf.netty.nettyapi.javabean.NettyMessage;
import io.netty.channel.ChannelHandlerAdapter;
import io.netty.channel.ChannelHandlerContext;
import lombok.extern.slf4j.Slf4j;import java.io.RandomAccessFile;
import java.util.Arrays;
import java.util.concurrent.TimeUnit;

/**
 * 客户端处理类
 */
@Slf4j
public class NettyClientHandler extends ChannelHandlerAdapter {

    private static final String AUDIO_PATH = "D:\\input\\寒号鸟.wav";

    @Override
    public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
        NettyMessage nettyMessage = (NettyMessage) msg;

        // 接收控制数据响应消息成功，每5秒发送pcm数据
        if (nettyMessage.getHeader() != null && nettyMessage.getHeader().getType() == (byte) 0) {
//            ctx.writeAndFlush(buildClientRequest());
//        }
            // 音频文件总时长，单位：秒
            int audioTotal = 122;
            try (RandomAccessFile raf = new RandomAccessFile(AUDIO_PATH, "r")) {

                // 读结束标志
                boolean readFinish = false;

                // 文件总字节数
                long audioLength = raf.length();

                // 每次发送字节数
                long eachLength = audioLength * 5 / audioTotal;

                // 音频数据
                byte[] audioData = null;
                byte[] bytes = new byte[1024];

                long cuccrentLength = 0L;

                // 读取音频文件
                while (true) {
                    // 休眠5秒
                    TimeUnit.SECONDS.sleep(5);

                    // 获取当前时间
                    long startTime = System.currentTimeMillis();
                    while (cuccrentLength <= eachLength) {

                        // 获取5秒内的音频字节流
                        int len = raf.read(bytes);
                        if (len == -1) {
                            readFinish = true;
                            break;
                        }

                        bytes = Arrays.copyOf(bytes, len);
                        audioData = ArrayUtils.addAll(audioData, bytes);
                        cuccrentLength += len;
                    }

                    // 发送5秒的数据包
                    NettyMessage nettyClientApi = buildNettyClientRequest(audioData, startTime);
                    log.info("[client] send client msg : {}", nettyClientApi);
                    ctx.writeAndFlush(nettyClientApi);

                    // 读完了
                    if (readFinish) {
                        log.info("The audio data send finish...");
                        break;
                    }

                    // 重置
                    cuccrentLength = 0L;
                }
            }
        }
    }

   /**
     * long转字节
     *
     * @param values
     * @return
     */
    private byte[] longToBytes(long values) {
        byte[] buffer = new byte[8];
        for (int i = 0; i < 8; i++) {
            int offset = 64 - (i + 1) * 8;
            buffer[i] = (byte) ((values >> offset) & 0xff);
        }
        return buffer;
    }

    /**
     * 将两个数组合并起来
     *
     * @param array1
     * @param array2
     * @return
     */
    private byte[] addAll(byte[] array1, byte... array2) {
        byte[] joinedArray = new byte[array1.length + array2.length];
        System.arraycopy(array1, 0, joinedArray, 0, array1.length);
        System.arraycopy(array2, 0, joinedArray, array1.length, array2.length);
        return joinedArray;
    }

    /**
     * 在处理过程中引发异常时被调用
     *
     * @param ctx
     * @param cause
     * @throws Exception
     */
    @Override
    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
        log.error("[Client] netty client request error: {}", cause.getMessage());
        ctx.close();
    }

    /**
     * 创建请求消息体
     *
     * @param audioData
     * @param time
     * @return
     */
    private NettyMessage buildNettyClientRequest(byte[] audioData, long time) {
        NettyMessage nettyMessage = new NettyMessage();
        Header header = new Header();
        byte[] data = buildPcmData(audioData, time);
        header.setDelimiter(0xABEF0101);
        header.setLength(data.length);
        header.setType((byte) 1);
        header.setReserved((byte) 0);
        nettyMessage.setHeader(header);

        // 设置数据包
        nettyMessage.setData(data);
        return nettyMessage;
    }

    /**
     * 构造PCM请求消息体
     *
     * @return
     */
    private byte[] buildPcmData(byte[] audioData, long time) {
        byte[] timeByte = longToBytes(time);

        return addAll(timeByte, audioData);
    }

}

　　重启客户端，会发现输出变成这样：

23:35:34.339 [nioEventLoopGroup-1-0] INFO com.wlf.netty.nettyclient.handler.HeartBeatClientHandler - [client] control response is OK, header : Header{delimiter=-1410399999, length=8, type=0, reserved=0}. sid : 56, interval : 5000
23:35:48.216 [nioEventLoopGroup-1-0] INFO com.wlf.netty.nettyclient.handler.NettyClientHandler - [client] send client msg : NettyMessage{header=Header{delimiter=-1410399999, length=161800, type=1, reserved=0}, data=[B@60deb0fd}
23:35:53.259 [nioEventLoopGroup-1-0] INFO com.wlf.netty.nettyclient.handler.NettyClientHandler - [client] send client msg : NettyMessage{header=Header{delimiter=-1410399999, length=323592, type=1, reserved=0}, data=[B@6f7f091e}
23:35:58.319 [nioEventLoopGroup-1-0] INFO com.wlf.netty.nettyclient.handler.NettyClientHandler - [client] send client msg : NettyMessage{header=Header{delimiter=-1410399999, length=485384, type=1, reserved=0}, data=[B@1c9231b2}
23:36:03.361 [nioEventLoopGroup-1-0] INFO com.wlf.netty.nettyclient.handler.NettyClientHandler - [client] send client msg : NettyMessage{header=Header{delimiter=-1410399999, length=647176, type=1, reserved=0}, data=[B@35f278be}
23:36:08.433 [nioEventLoopGroup-1-0] INFO com.wlf.netty.nettyclient.handler.NettyClientHandler - [client] send client msg : NettyMessage{header=Header{delimiter=-1410399999, length=808968, type=1, reserved=0}, data=[B@20be6fa5}
23:36:13.496 [nioEventLoopGroup-1-0] INFO com.wlf.netty.nettyclient.handler.NettyClientHandler - [client] send client msg : NettyMessage{header=Header{delimiter=-1410399999, length=970760, type=1, reserved=0}, data=[B@371eb555}
23:36:18.607 [nioEventLoopGroup-1-0] INFO com.wlf.netty.nettyclient.handler.NettyClientHandler - [client] send client msg : NettyMessage{header=Header{delimiter=-1410399999, length=1132552, type=1, reserved=0}, data=[B@3a8c0da5}
23:36:23.694 [nioEventLoopGroup-1-0] INFO com.wlf.netty.nettyclient.handler.NettyClientHandler - [client] send client msg : NettyMessage{header=Header{delimiter=-1410399999, length=1294344, type=1, reserved=0}, data=[B@1c9da5c2}
23:36:28.855 [nioEventLoopGroup-1-0] INFO com.wlf.netty.nettyclient.handler.NettyClientHandler - [client] send client msg : NettyMessage{header=Header{delimiter=-1410399999, length=1456136, type=1, reserved=0}, data=[B@4f0d32b3}
23:36:33.974 [nioEventLoopGroup-1-0] INFO com.wlf.netty.nettyclient.handler.NettyClientHandler - [client] send client msg : NettyMessage{header=Header{delimiter=-1410399999, length=1617928, type=1, reserved=0}, data=[B@d7b821a}
23:36:39.134 [nioEventLoopGroup-1-0] INFO com.wlf.netty.nettyclient.handler.NettyClientHandler - [client] send client msg : NettyMessage{header=Header{delimiter=-1410399999, length=1779720, type=1, reserved=0}, data=[B@57404735}
23:36:44.272 [nioEventLoopGroup-1-0] INFO com.wlf.netty.nettyclient.handler.NettyClientHandler - [client] send client msg : NettyMessage{header=Header{delimiter=-1410399999, length=1941512, type=1, reserved=0}, data=[B@26825baa}
23:36:49.410 [nioEventLoopGroup-1-0] INFO com.wlf.netty.nettyclient.handler.NettyClientHandler - [client] send client msg : NettyMessage{header=Header{delimiter=-1410399999, length=2103304, type=1, reserved=0}, data=[B@bc7d63}
23:36:54.650 [nioEventLoopGroup-1-0] INFO com.wlf.netty.nettyclient.handler.NettyClientHandler - [client] send client msg : NettyMessage{header=Header{delimiter=-1410399999, length=2265096, type=1, reserved=0}, data=[B@5106443c}
23:36:59.816 [nioEventLoopGroup-1-0] INFO com.wlf.netty.nettyclient.handler.NettyClientHandler - [client] send client msg : NettyMessage{header=Header{delimiter=-1410399999, length=2426888, type=1, reserved=0}, data=[B@4aac8c6}
23:37:05.009 [nioEventLoopGroup-1-0] INFO com.wlf.netty.nettyclient.handler.NettyClientHandler - [client] send client msg : NettyMessage{header=Header{delimiter=-1410399999, length=2588680, type=1, reserved=0}, data=[B@30419cf2}
23:37:10.200 [nioEventLoopGroup-1-0] INFO com.wlf.netty.nettyclient.handler.NettyClientHandler - [client] send client msg : NettyMessage{header=Header{delimiter=-1410399999, length=2750472, type=1, reserved=0}, data=[B@53f5b8fc}
23:37:15.416 [nioEventLoopGroup-1-0] INFO com.wlf.netty.nettyclient.handler.NettyClientHandler - [client] send client msg : NettyMessage{header=Header{delimiter=-1410399999, length=2912264, type=1, reserved=0}, data=[B@3031311a}
23:37:20.633 [nioEventLoopGroup-1-0] INFO com.wlf.netty.nettyclient.handler.NettyClientHandler - [client] send client msg : NettyMessage{header=Header{delimiter=-1410399999, length=3074056, type=1, reserved=0}, data=[B@628f3322}
23:37:25.886 [nioEventLoopGroup-1-0] INFO com.wlf.netty.nettyclient.handler.NettyClientHandler - [client] send client msg : NettyMessage{header=Header{delimiter=-1410399999, length=3235848, type=1, reserved=0}, data=[B@5e95858d}

　　心跳根本没进来，因为业务消息占用了事件循环的IO线程，还轮不到心跳消息的发送，除非当前的业务消息发送完了。反之亦然，如果是先发送心跳，那业务消息就别指望有机会发送了，因为心跳根本就停不下来。怎么办？两种解决方案，一种是采用netty自带的IdleStateHandler来做心跳，它不会占用IO线程，因为它采用的是事件检测；另一种就是把业务消息和心跳消息糅合到一起，既然都是定时发送，那就放一起好了，只不过这样一来定时的时间间隔就必须一致了。我们在心跳Handler中带上业务消息：

package com.wlf.netty.nettyclient.handler;

import com.wlf.netty.nettyapi.javabean.Header;
import com.wlf.netty.nettyapi.javabean.NettyMessage;
import com.wlf.netty.nettyapi.util.CommonUtil;
import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelHandlerAdapter;
import io.netty.channel.ChannelHandlerContext;
import io.netty.util.concurrent.ScheduledFuture;
import lombok.extern.slf4j.Slf4j;

import java.io.RandomAccessFile;
import java.util.Arrays;
import java.util.concurrent.TimeUnit;

@Slf4j
public class HeartBeatClientHandler extends ChannelHandlerAdapter {
    private static final String AUDIO_PATH = "D:\\input\\寒号鸟.wav";
    private volatile int interval = 5000;
    private volatile ScheduledFuture<?> heartBeat;

    @Override
    public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
        NettyMessage nettyMessage = (NettyMessage) msg;

        // 接收控制数据响应消息成功，发送心跳给服务端
        if (nettyMessage.getHeader() != null && nettyMessage.getHeader().getType() == (byte) 0) {
            byte[] data = nettyMessage.getData();
            ByteBuf buf = Unpooled.buffer(8);
            buf.writeBytes(data);
            int sid = buf.readInt();
            interval = buf.readInt();
            log.info("[client] control response is OK, header : {}. sid : {}, interval : {}", nettyMessage.getHeader(), sid, interval);

            // 每interval（默认5000）豪秒发送一次心跳请求到服务端
//            heartBeat = ctx.executor().scheduleAtFixedRate(new Runnable() {
//                                                               @Override
//                                                               public void run() {
//                                                                   NettyMessage heartBeat = buildHeartBeat(sid);
//                                                                   log.info("[client] Client send heart beat message to server : ----> {}", heartBeat);
//                                                                   ctx.writeAndFlush(heartBeat);
//                                                               }
//                                                           },
//                    0, interval, TimeUnit.MILLISECONDS);

            // 音频文件总时长，单位：秒
            int audioTotal = 122;
            try (RandomAccessFile raf = new RandomAccessFile(AUDIO_PATH, "r")) {

                // 读结束标志
                boolean readFinish = false;

                // 文件总字节数
                long audioLength = raf.length();

                // 每次发送字节数
                long eachLength = audioLength * 5 / audioTotal;

                // 音频数据
                byte[] audioData = null;
                byte[] bytes = new byte[1024];

                long cuccrentLength = 0L;

                // 读取音频文件
                while (true) {
                    // 休眠5秒
                    TimeUnit.SECONDS.sleep(5);

                    // 获取当前时间
                    long startTime = System.currentTimeMillis();
                    do {

                        // 获取5秒内的音频字节流
                        int len = raf.read(bytes);
                        if (len == -1) {
                            readFinish = true;
                            break;
                        }

                        bytes = Arrays.copyOf(bytes, len);
                        audioData = ArrayUtils.addAll(audioData, bytes);
                        cuccrentLength += len;
                    } while (cuccrentLength <= eachLength);

                    // 发送心跳
                    NettyMessage heartBeat = buildHeartBeat(sid);
                    log.info("[client] Client send heart beat message to server : ----> {}", heartBeat);
                    ctx.writeAndFlush(heartBeat);

                    // 发送5秒的数据包
                    NettyMessage nettyClientApi = buildNettyClientRequest(audioData, startTime);
                    log.info("[client] Client send business message to server : ----> {}", nettyClientApi);
                    ctx.writeAndFlush(nettyClientApi);

                    // 读完了
                    if (readFinish) {
                        log.info("The audio data send finish...");
                        break;
                    }

                    // 重置
                    cuccrentLength = 0L;
                    audioData = null;
                }
            }
        } else if (nettyMessage.getHeader() != null && nettyMessage.getHeader().getType() == (byte) 2) {
            log.info("[client] receive server business : {}", nettyMessage);
        } else {
            ctx.fireChannelRead(msg);
        }
    }

    @Override
    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
        log.error("[Client] heart request error: {}", cause.getMessage());
        if (heartBeat != null) {
            heartBeat.cancel(true);
            heartBeat = null;
        }
        ctx.fireExceptionCaught(cause);
    }

    /**
     * 构造心跳请求消息体
     *
     * @return
     */
    private NettyMessage buildHeartBeat(int sid) {
        NettyMessage message = new NettyMessage();
        Header header = new Header();
        byte[] data = buildData(sid);
        header.setDelimiter(0xABEF0101);
        header.setLength(data.length);
        header.setType((byte) 3);
        header.setReserved((byte) 0);
        message.setHeader(header);

        // 设置数据包
        message.setData(data);
        return message;
    }

    /**
     * 构建心跳响应消息体
     *
     * @param sid
     * @return
     */
    private byte[] buildData(int sid) {
        ByteBuf result = Unpooled.buffer(4);
        result.writeInt(sid);
        return result.array();
    }

    /**
     * 创建请求消息体
     *
     * @param audioData
     * @param time
     * @return
     */
    private NettyMessage buildNettyClientRequest(byte[] audioData, long time) {
        NettyMessage nettyMessage = new NettyMessage();
        Header header = new Header();
        byte[] data = buildPcmData(audioData, time);
        header.setDelimiter(Delimiter.DELIMITER);
        header.setLength(data.length);
        header.setType(MessageType.PCM_TYPE.getType());
        header.setReserved((byte) 0);
        nettyMessage.setHeader(header);

        // 设置数据包
        nettyMessage.setData(data);
        return nettyMessage;
    }

    /**
     * 构造PCM请求消息体
     *
     * @return
     */
    private byte[] buildPcmData(byte[] audioData, long time) {
        byte[] timeByte = CommonUtil.longToBytes(time);

        return addAll(timeByte, audioData);
    }

    /**
     * long转字节
     *
     * @param values
     * @return
     */
    private byte[] longToBytes(long values) {
        byte[] buffer = new byte[8];
        for (int i = 0; i < 8; i++) {
            int offset = 64 - (i + 1) * 8;
            buffer[i] = (byte) ((values >> offset) & 0xff);
        }
        return buffer;
    }

    /**
     * 将两个数组合并起来
     *
     * @param array1
     * @param array2
     * @return
     */
    private byte[] addAll(byte[] array1, byte... array2) {
        byte[] joinedArray = new byte[array1.length + array2.length];
        System.arraycopy(array1, 0, joinedArray, 0, array1.length);
        System.arraycopy(array2, 0, joinedArray, array1.length, array2.length);
        return joinedArray;
    }

}

　　至于原来的NettyClientHandler相当于废了，在引导类中名存实亡。重启NettyClient，输出如下：

15:45:07.442 [nioEventLoopGroup-1-2] INFO com.wlf.netty.nettyclient.handler.HeartBeatClientHandler - [client] control response is OK, header : Header{delimiter=-1410399999, length=8, type=0, reserved=0}. sid : 94, interval : 5000
15:45:12.499 [nioEventLoopGroup-1-2] INFO com.wlf.netty.nettyclient.handler.HeartBeatClientHandler - [client] Client send heart beat message to server : ----> NettyMessage{header=Header{delimiter=-1410399999, length=4, type=3, reserved=0}, data=[B@2bf023ed}
15:45:12.504 [nioEventLoopGroup-1-2] INFO com.wlf.netty.nettyclient.handler.HeartBeatClientHandler - [client] Client send business message to server : ----> NettyMessage{header=Header{delimiter=-1410399999, length=161800, type=1, reserved=0}, data=[B@b1ad25a}
15:45:17.519 [nioEventLoopGroup-1-2] INFO com.wlf.netty.nettyclient.handler.HeartBeatClientHandler - [client] Client send heart beat message to server : ----> NettyMessage{header=Header{delimiter=-1410399999, length=4, type=3, reserved=0}, data=[B@44fb731d}
15:45:17.520 [nioEventLoopGroup-1-2] INFO com.wlf.netty.nettyclient.handler.HeartBeatClientHandler - [client] Client send business message to server : ----> NettyMessage{header=Header{delimiter=-1410399999, length=161800, type=1, reserved=0}, data=[B@253b550c}
15:45:22.551 [nioEventLoopGroup-1-2] INFO com.wlf.netty.nettyclient.handler.HeartBeatClientHandler - [client] Client send heart beat message to server : ----> NettyMessage{header=Header{delimiter=-1410399999, length=4, type=3, reserved=0}, data=[B@f7ef50d}
15:45:22.552 [nioEventLoopGroup-1-2] INFO com.wlf.netty.nettyclient.handler.HeartBeatClientHandler - [client] Client send business message to server : ----> NettyMessage{header=Header{delimiter=-1410399999, length=161800, type=1, reserved=0}, data=[B@52ab6eba}
15:45:27.565 [nioEventLoopGroup-1-2] INFO com.wlf.netty.nettyclient.handler.HeartBeatClientHandler - [client] Client send heart beat message to server : ----> NettyMessage{header=Header{delimiter=-1410399999, length=4, type=3, reserved=0}, data=[B@4d578c69}
15:45:27.565 [nioEventLoopGroup-1-2] INFO com.wlf.netty.nettyclient.handler.HeartBeatClientHandler - [client] Client send business message to server : ----> NettyMessage{header=Header{delimiter=-1410399999, length=161800, type=1, reserved=0}, data=[B@323b23fa}
15:45:32.598 [nioEventLoopGroup-1-2] INFO com.wlf.netty.nettyclient.handler.HeartBeatClientHandler - [client] Client send heart beat message to server : ----> NettyMessage{header=Header{delimiter=-1410399999, length=4, type=3, reserved=0}, data=[B@4a957e2d}
15:45:32.598 [nioEventLoopGroup-1-2] INFO com.wlf.netty.nettyclient.handler.HeartBeatClientHandler - [client] Client send business message to server : ----> NettyMessage{header=Header{delimiter=-1410399999, length=161800, type=1, reserved=0}, data=[B@43c2077b}
15:45:37.623 [nioEventLoopGroup-1-2] INFO com.wlf.netty.nettyclient.handler.HeartBeatClientHandler - [client] Client send heart beat message to server : ----> NettyMessage{header=Header{delimiter=-1410399999, length=4, type=3, reserved=0}, data=[B@3207ffae}