[笔记]-netty-nioeventloopgroup

public class  extends MultithreadEventLoopGroup {

    public () {
        
        this(0);
    }

    public (int nThreads) {
        // Executor null
        this(nThreads, (Executor) null);
    }

    public (int nThreads, Executor executor) {
        // SelectorProvider
        this(nThreads, executor, SelectorProvider.provider());
    }

    public (int nThreads, Executor executor, final SelectorProvider selectorProvider) {
        // 默认的Select策略
        this(nThreads, executor, selectorProvider, DefaultSelectStrategyFactory.INSTANCE);
    }

    public NioEventLoopGroup(int nThreads, Executor executor, final SelectorProvider selectorProvider, final SelectStrategyFactory selectStrategyFactory) {
        // 默认的拒绝处理
        super(nThreads, executor, selectorProvider, selectStrategyFactory, RejectedExecutionHandlers.reject());
    }

    
    protected EventLoop newChild(Executor executor, Object... args) throws Exception {
        // NioEventLoop的父级是该NioEventLoopGroup
        return new NioEventLoop(this, executor, (SelectorProvider) args[0], ((SelectStrategyFactory) args[1]).newSelectStrategy(), (RejectedExecutionHandler) args[2]);
    }
}

public abstract class MultithreadEventLoopGroup extends MultithreadEventExecutorGroup implements EventLoopGroup {

    protected MultithreadEventLoopGroup(int nThreads, Executor executor, Object... args) {
        // 默认CPU核心数*2
        super(nThreads == 0 ? DEFAULT_EVENT_LOOP_THREADS : nThreads, executor, args);
    }

}

public abstract class MultithreadEventExecutorGroup extends AbstractEventExecutorGroup {

    /**
     * 线程
     */
    private final EventExecutor[] children;
    private final Set<EventExecutor> readonlyChildren;
    private final AtomicInteger terminatedChildren = new AtomicInteger();

    /**
     * 线程选择器
     */
    private final EventExecutorChooserFactory.EventExecutorChooser chooser;

    protected MultithreadEventExecutorGroup(int nThreads, Executor executor, Object... args) {
        // .. .. 线程选择器 ..
        this(nThreads, executor, DefaultEventExecutorChooserFactory.INSTANCE, args);
    }

    protected MultithreadEventExecutorGroup(int nThreads, Executor executor, EventExecutorChooserFactory chooserFactory, Object... args) {
        if (nThreads <= 0) {
            // ...
        }
        if (executor == null) {
            // 默认的执行器，execute就新开线程执行
            executor = new ThreadPerTaskExecutor(newDefaultThreadFactory());
        }
        // 线程组
        children = new EventExecutor[nThreads];

        for (int i = 0; i < nThreads; i++) {
            boolean success = false;
            try {
                // 创建线程
                children[i] = newChild(executor, args);
                success = true;
            } catch (Exception e) {
                // ...
            } finally {
                if (!success) {
                    // ...
                }
            }
        }
        // 根据线程数量返回选择器
        chooser = chooserFactory.newChooser(children);

        final FutureListener<Object> terminationListener = new FutureListener<Object>() {
            
            public void operationComplete(Future<Object> future) throws Exception {
                // ...
            }
        };

        for (EventExecutor e : children) {
            e.terminationFuture().addListener(terminationListener);
        }

        Set<EventExecutor> childrenSet = new LinkedHashSet<EventExecutor>(children.length);
        Collections.addAll(childrenSet, children);
        readonlyChildren = Collections.unmodifiableSet(childrenSet);
    }

}