reactor-netty之client与server如何共用EventLoopGroup

直接到DefaultLoopResources类中，可以看到两个方法

    @Override
    public EventLoopGroup onClient(boolean useNative) {
        if (useNative && LoopResources.hasNativeSupport()) {
            return cacheNativeClientLoops();
        }
        return cacheNioClientLoops();
    }

    @Override
    public EventLoopGroup onServer(boolean useNative) {
        if (useNative && LoopResources.hasNativeSupport()) {
            return cacheNativeServerLoops();
        }
        return cacheNioServerLoops();
    }

然后进入cacheNativeClientLoops()中

    EventLoopGroup cacheNativeClientLoops() {
        EventLoopGroup eventLoopGroup = cacheNativeClientLoops.get();
        if (null == eventLoopGroup) {
            EventLoopGroup newEventLoopGroup = LoopResources.colocate(cacheNativeServerLoops());
            if (!cacheNativeClientLoops.compareAndSet(null, newEventLoopGroup)) {
                // Do not shutdown newEventLoopGroup as this will shutdown the server loops
            }
            eventLoopGroup = cacheNativeClientLoops();
        }
        return eventLoopGroup;
    }

可以看到调了cacheNativeServerLoops()方法，实现了与server共用EventLoopGroup.
那么在编程中， 如何指定EventLoopGroup线程数呢？那么请转到reactor.netty.resources.LoopResources中

int DEFAULT_IO_WORKER_COUNT = Integer.parseInt(System.getProperty(
            ReactorNetty.IO_WORKER_COUNT,
            "" + Math.max(Runtime.getRuntime().availableProcessors(), 4)));

其中ReactorNetty.IO_WORKER_COUNT值为"reactor.netty.ioWorkerCount", 那可以简单通过设置这个值来实现。