5.0.2 无法优雅关机

• I have searched the issues of this repository and believe that this is not a duplicate.

1. Bug Description

程序在停机时（kill PID），会断开与tm的netty链接，但是链接断开后又会引起重连，因此引发无法优雅关机，最后不得不使用 kill -9 PID 的方式来强杀

2. Environment:

• JDK version:1.8
• OS:win10
• TX-LCN version:5.0.2
• Others:

3. Exception Stacktrace

[2019-08-01 10:18:01.480] [nioEventLoopGroup-5-3] [ERROR] io.netty.util.concurrent.DefaultPromise.rejectedExecution [181] - Failed to submit a listener notification task. Event loop shut down?
java.util.concurrent.RejectedExecutionException: event executor terminated
        at io.netty.util.concurrent.SingleThreadEventExecutor.reject(SingleThreadEventExecutor.java:842)
        at io.netty.util.concurrent.SingleThreadEventExecutor.offerTask(SingleThreadEventExecutor.java:328)
        at io.netty.util.concurrent.SingleThreadEventExecutor.addTask(SingleThreadEventExecutor.java:321)
        at io.netty.util.concurrent.SingleThreadEventExecutor.execute(SingleThreadEventExecutor.java:765)
        at io.netty.util.concurrent.DefaultPromise.safeExecute(DefaultPromise.java:768)
        at io.netty.util.concurrent.DefaultPromise.notifyListeners(DefaultPromise.java:432)
        at io.netty.util.concurrent.DefaultPromise.trySuccess(DefaultPromise.java:103)
        at io.netty.channel.DefaultChannelPromise.trySuccess(DefaultChannelPromise.java:84)
        at io.netty.channel.AbstractChannel$CloseFuture.setClosed(AbstractChannel.java:1148)
        at io.netty.channel.AbstractChannel$AbstractUnsafe.register(AbstractChannel.java:490)
        at io.netty.channel.SingleThreadEventLoop.register(SingleThreadEventLoop.java:80)
        at io.netty.channel.SingleThreadEventLoop.register(SingleThreadEventLoop.java:74)
        at io.netty.channel.MultithreadEventLoopGroup.register(MultithreadEventLoopGroup.java:86)
        at io.netty.bootstrap.AbstractBootstrap.initAndRegister(AbstractBootstrap.java:333)
        at io.netty.bootstrap.Bootstrap.doResolveAndConnect(Bootstrap.java:163)
        at io.netty.bootstrap.Bootstrap.connect(Bootstrap.java:145)
        at com.codingapi.txlcn.txmsg.netty.impl.NettyRpcClientInitializer.connect(NettyRpcClientInitializer.java:109)
        at com.codingapi.txlcn.txmsg.netty.impl.NettyRpcClientInitializer.reConnect(NettyRpcClientInitializer.java:76)
        at com.codingapi.txlcn.txmsg.netty.handler.NettyClientRetryHandler.channelInactive(NettyClientRetryHandler.java:79)
        at io.netty.channel.AbstractChannelHandlerContext.invokeChannelInactive(AbstractChannelHandlerContext.java:245)
        at io.netty.channel.AbstractChannelHandlerContext.invokeChannelInactive(AbstractChannelHandlerContext.java:231)
        at io.netty.channel.AbstractChannelHandlerContext.fireChannelInactive(AbstractChannelHandlerContext.java:224)
        at io.netty.channel.ChannelInboundHandlerAdapter.channelInactive(ChannelInboundHandlerAdapter.java:75)
        at io.netty.channel.AbstractChannelHandlerContext.invokeChannelInactive(AbstractChannelHandlerContext.java:245)
        at io.netty.channel.AbstractChannelHandlerContext.invokeChannelInactive(AbstractChannelHandlerContext.java:231)
        at io.netty.channel.AbstractChannelHandlerContext.fireChannelInactive(AbstractChannelHandlerContext.java:224)
        at io.netty.channel.ChannelInboundHandlerAdapter.channelInactive(ChannelInboundHandlerAdapter.java:75)
        at io.netty.channel.AbstractChannelHandlerContext.invokeChannelInactive(AbstractChannelHandlerContext.java:245)
        at io.netty.channel.AbstractChannelHandlerContext.invokeChannelInactive(AbstractChannelHandlerContext.java:231)
        at io.netty.channel.AbstractChannelHandlerContext.fireChannelInactive(AbstractChannelHandlerContext.java:224)
        at io.netty.handler.codec.ByteToMessageDecoder.channelInputClosed(ByteToMessageDecoder.java:377)
        at io.netty.handler.codec.ByteToMessageDecoder.channelInactive(ByteToMessageDecoder.java:342)
        at io.netty.channel.AbstractChannelHandlerContext.invokeChannelInactive(AbstractChannelHandlerContext.java:245)
        at io.netty.channel.AbstractChannelHandlerContext.invokeChannelInactive(AbstractChannelHandlerContext.java:231)
        at io.netty.channel.AbstractChannelHandlerContext.fireChannelInactive(AbstractChannelHandlerContext.java:224)
        at io.netty.channel.DefaultChannelPipeline$HeadContext.channelInactive(DefaultChannelPipeline.java:1429)
        at io.netty.channel.AbstractChannelHandlerContext.invokeChannelInactive(AbstractChannelHandlerContext.java:245)
        at io.netty.channel.AbstractChannelHandlerContext.invokeChannelInactive(AbstractChannelHandlerContext.java:231)
        at io.netty.channel.DefaultChannelPipeline.fireChannelInactive(DefaultChannelPipeline.java:947)
        at io.netty.channel.AbstractChannel$AbstractUnsafe$8.run(AbstractChannel.java:822)
        at io.netty.util.concurrent.AbstractEventExecutor.safeExecute(AbstractEventExecutor.java:163)
        at io.netty.util.concurrent.SingleThreadEventExecutor.runAllTasksFrom(SingleThreadEventExecutor.java:380)
        at io.netty.util.concurrent.SingleThreadEventExecutor.runAllTasks(SingleThreadEventExecutor.java:355)
        at io.netty.util.concurrent.SingleThreadEventExecutor.confirmShutdown(SingleThreadEventExecutor.java:701)
        at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:456)
        at io.netty.util.concurrent.SingleThreadEventExecutor$5.run(SingleThreadEventExecutor.java:884)
        at io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30)
        at java.lang.Thread.run(Thread.java:745)

4. Tour Idea

Bắt đầu với NettyRpcClientInitializer.connect/reConnect và NettyClientRetryHandler.channelInactive, sử dụng stack trace làm điểm bắt đầu. Theo dõi việc xử lý shutdown xung quanh kết nối Netty và luồng retry. Hoàn thành khi việc dừng tiến trình không kích hoạt thêm một lần kết nối lại nào và không tạo ra lỗi thực thi bị từ chối, cho phép shutdown một cách an toàn.