聊聊rocketmq的RemotingSendRequestException

序

本文主要研究一下rocketmq的RemotingSendRequestException

RemotingSendRequestException

rocketmq-remoting-4.6.0-sources.jar!/org/apache/rocketmq/remoting/exception/RemotingSendRequestException.java

public class RemotingSendRequestException extends RemotingException {
    private static final long serialVersionUID = 5391285827332471674L;

    public RemotingSendRequestException(String addr) {
        this(addr, null);
    }

    public RemotingSendRequestException(String addr, Throwable cause) {
        super("send request to <" + addr + "> failed", cause);
    }
}

• RemotingSendRequestException继承了RemotingException，它的构造器要求addr参数

invokeSyncImpl

rocketmq-remoting-4.6.0-sources.jar!/org/apache/rocketmq/remoting/netty/NettyRemotingAbstract.java

public abstract class NettyRemotingAbstract {
    //......

    public RemotingCommand invokeSyncImpl(final Channel channel, final RemotingCommand request,
        final long timeoutMillis)
        throws InterruptedException, RemotingSendRequestException, RemotingTimeoutException {
        final int opaque = request.getOpaque();

        try {
            final ResponseFuture responseFuture = new ResponseFuture(channel, opaque, timeoutMillis, null, null);
            this.responseTable.put(opaque, responseFuture);
            final SocketAddress addr = channel.remoteAddress();
            channel.writeAndFlush(request).addListener(new ChannelFutureListener() {
                @Override
                public void operationComplete(ChannelFuture f) throws Exception {
                    if (f.isSuccess()) {
                        responseFuture.setSendRequestOK(true);
                        return;
                    } else {
                        responseFuture.setSendRequestOK(false);
                    }

                    responseTable.remove(opaque);
                    responseFuture.setCause(f.cause());
                    responseFuture.putResponse(null);
                    log.warn("send a request command to channel <" + addr + "> failed.");
                }
            });

            RemotingCommand responseCommand = responseFuture.waitResponse(timeoutMillis);
            if (null == responseCommand) {
                if (responseFuture.isSendRequestOK()) {
                    throw new RemotingTimeoutException(RemotingHelper.parseSocketAddressAddr(addr), timeoutMillis,
                        responseFuture.getCause());
                } else {
                    throw new RemotingSendRequestException(RemotingHelper.parseSocketAddressAddr(addr), responseFuture.getCause());
                }
            }

            return responseCommand;
        } finally {
            this.responseTable.remove(opaque);
        }
    }

    //......
}

• invokeSyncImpl方法在responseCommand为null且responseFuture.isSendRequestOK()为false的时候抛出RemotingSendRequestException

invokeAsyncImpl

rocketmq-remoting-4.6.0-sources.jar!/org/apache/rocketmq/remoting/netty/NettyRemotingAbstract.java

public abstract class NettyRemotingAbstract {
    //......

    public void invokeAsyncImpl(final Channel channel, final RemotingCommand request, final long timeoutMillis,
        final InvokeCallback invokeCallback)
        throws InterruptedException, RemotingTooMuchRequestException, RemotingTimeoutException, RemotingSendRequestException {
        long beginStartTime = System.currentTimeMillis();
        final int opaque = request.getOpaque();
        boolean acquired = this.semaphoreAsync.tryAcquire(timeoutMillis, TimeUnit.MILLISECONDS);
        if (acquired) {
            final SemaphoreReleaseOnlyOnce once = new SemaphoreReleaseOnlyOnce(this.semaphoreAsync);
            long costTime = System.currentTimeMillis() - beginStartTime;
            if (timeoutMillis < costTime) {
                once.release();
                throw new RemotingTimeoutException("invokeAsyncImpl call timeout");
            }

            final ResponseFuture responseFuture = new ResponseFuture(channel, opaque, timeoutMillis - costTime, invokeCallback, once);
            this.responseTable.put(opaque, responseFuture);
            try {
                channel.writeAndFlush(request).addListener(new ChannelFutureListener() {
                    @Override
                    public void operationComplete(ChannelFuture f) throws Exception {
                        if (f.isSuccess()) {
                            responseFuture.setSendRequestOK(true);
                            return;
                        }
                        requestFail(opaque);
                        log.warn("send a request command to channel <{}> failed.", RemotingHelper.parseChannelRemoteAddr(channel));
                    }
                });
            } catch (Exception e) {
                responseFuture.release();
                log.warn("send a request command to channel <" + RemotingHelper.parseChannelRemoteAddr(channel) + "> Exception", e);
                throw new RemotingSendRequestException(RemotingHelper.parseChannelRemoteAddr(channel), e);
            }
        } else {
            if (timeoutMillis <= 0) {
                throw new RemotingTooMuchRequestException("invokeAsyncImpl invoke too fast");
            } else {
                String info =
                    String.format("invokeAsyncImpl tryAcquire semaphore timeout, %dms, waiting thread nums: %d semaphoreAsyncValue: %d",
                        timeoutMillis,
                        this.semaphoreAsync.getQueueLength(),
                        this.semaphoreAsync.availablePermits()
                    );
                log.warn(info);
                throw new RemotingTimeoutException(info);
            }
        }
    }

    //......
}

• invokeAsyncImpl在acquired为true，channel.writeAndFlush(request)抛出异常时，会将异常转为RemotingSendRequestException

invokeOnewayImpl

rocketmq-remoting-4.6.0-sources.jar!/org/apache/rocketmq/remoting/netty/NettyRemotingAbstract.java

public abstract class NettyRemotingAbstract {
    //......

    public void invokeOnewayImpl(final Channel channel, final RemotingCommand request, final long timeoutMillis)
        throws InterruptedException, RemotingTooMuchRequestException, RemotingTimeoutException, RemotingSendRequestException {
        request.markOnewayRPC();
        boolean acquired = this.semaphoreOneway.tryAcquire(timeoutMillis, TimeUnit.MILLISECONDS);
        if (acquired) {
            final SemaphoreReleaseOnlyOnce once = new SemaphoreReleaseOnlyOnce(this.semaphoreOneway);
            try {
                channel.writeAndFlush(request).addListener(new ChannelFutureListener() {
                    @Override
                    public void operationComplete(ChannelFuture f) throws Exception {
                        once.release();
                        if (!f.isSuccess()) {
                            log.warn("send a request command to channel <" + channel.remoteAddress() + "> failed.");
                        }
                    }
                });
            } catch (Exception e) {
                once.release();
                log.warn("write send a request command to channel <" + channel.remoteAddress() + "> failed.");
                throw new RemotingSendRequestException(RemotingHelper.parseChannelRemoteAddr(channel), e);
            }
        } else {
            if (timeoutMillis <= 0) {
                throw new RemotingTooMuchRequestException("invokeOnewayImpl invoke too fast");
            } else {
                String info = String.format(
                    "invokeOnewayImpl tryAcquire semaphore timeout, %dms, waiting thread nums: %d semaphoreAsyncValue: %d",
                    timeoutMillis,
                    this.semaphoreOneway.getQueueLength(),
                    this.semaphoreOneway.availablePermits()
                );
                log.warn(info);
                throw new RemotingTimeoutException(info);
            }
        }
    }

    //......
}

• invokeOnewayImpl在acquired为true，channel.writeAndFlush(request)抛出异常时，会将异常转为RemotingSendRequestException

小结

RemotingSendRequestException继承了RemotingException，它的构造器要求addr参数；invokeSyncImpl方法在responseCommand为null且responseFuture.isSendRequestOK()为false的时候抛出RemotingSendRequestException；invokeAsyncImpl在acquired为true，channel.writeAndFlush(request)抛出异常时，会将异常转为RemotingSendRequestException；invokeOnewayImpl在acquired为true，channel.writeAndFlush(request)抛出异常时，会将异常转为RemotingSendRequestException

doc

• NettyRemotingAbstract